/* roulang page: index */
:root {
  --c-bg: #0a0e17;
  --c-bg-soft: #0d1220;
  --c-surface: #111827;
  --c-surface-2: #151d2e;
  --c-border: rgba(0, 229, 255, 0.14);
  --c-border-strong: rgba(0, 229, 255, 0.35);
  --c-primary: #00e5ff;
  --c-secondary: #9d4edd;
  --c-accent: #ffcc4d;
  --c-text: #e6edf3;
  --c-text-weak: #8b98a9;
  --c-text-faint: #5b6675;
  --c-dark-line: rgba(255, 255, 255, 0.06);
  --c-white: #ffffff;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --radius-xl: 30px;
  --shadow-sm: 0 4px 16px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 10px 30px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 20px 50px rgba(0, 0, 0, 0.45);
  --shadow-neon: 0 0 24px rgba(0, 229, 255, 0.18);
  --gradient-main: linear-gradient(135deg, #00e5ff 0%, #9d4edd 100%);
  --gradient-soft: linear-gradient(135deg, rgba(0, 229, 255, 0.12), rgba(157, 78, 221, 0.12));
  --font-main: "Inter", system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --space-section: 96px;
  --space-section-md: 72px;
}
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-main);
  font-size: 16px;
  line-height: 1.75;
  color: var(--c-text);
  background: var(--c-bg);
  overflow-x: hidden;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(ellipse at 18% 8%, rgba(0, 229, 255, 0.08) 0%, transparent 45%),
    radial-gradient(ellipse at 82% 15%, rgba(157, 78, 221, 0.10) 0%, transparent 42%),
    radial-gradient(ellipse at 50% 90%, rgba(0, 229, 255, 0.05) 0%, transparent 50%),
    var(--c-bg);
}
a {
  color: var(--c-primary);
  text-decoration: none;
  transition: color .25s ease, opacity .25s ease;
}
a:hover { color: #52efff; }
img { max-width: 100%; height: auto; display: block; }
button { font-family: inherit; }
.container-custom {
  width: min(1200px, 92%);
  margin-inline: auto;
}
.section-block {
  padding-block: var(--space-section);
  position: relative;
}
.section-head {
  text-align: center;
  max-width: 720px;
  margin-inline: auto;
  margin-bottom: 52px;
}
.section-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--c-primary);
  background: rgba(0, 229, 255, 0.08);
  border: 1px solid rgba(0, 229, 255, 0.2);
  padding: 6px 16px;
  border-radius: 100px;
  margin-bottom: 14px;
}
.section-title {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--c-white);
  margin: 0 0 14px;
}
.section-subtitle {
  font-size: 16px;
  color: var(--c-text-weak);
  line-height: 1.8;
  margin: 0;
}
.text-gradient {
  background: var(--gradient-main);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}
.btn-neon {
  --btn-bg: var(--gradient-main);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-weight: 700;
  font-size: 15px;
  color: #041018;
  background: var(--btn-bg);
  border: none;
  padding: 13px 30px;
  border-radius: 100px;
  box-shadow: 0 6px 24px rgba(0, 229, 255, 0.25);
  transition: transform .3s ease, box-shadow .3s ease, filter .3s ease;
  letter-spacing: 0.02em;
}
.btn-neon:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 36px rgba(0, 229, 255, 0.35);
  filter: brightness(1.08);
  color: #041018;
}
.btn-neon:active { transform: translateY(0); box-shadow: 0 4px 14px rgba(0, 229, 255, 0.2); }
.btn-neon:focus-visible { outline: 3px solid rgba(0, 229, 255, 0.5); outline-offset: 3px; }
.btn-outline-neon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-weight: 700;
  font-size: 15px;
  color: var(--c-primary);
  background: transparent;
  border: 1px solid var(--c-border-strong);
  padding: 12px 28px;
  border-radius: 100px;
  transition: all .3s ease;
}
.btn-outline-neon:hover {
  background: rgba(0, 229, 255, 0.08);
  box-shadow: var(--shadow-neon);
  color: var(--c-primary);
  transform: translateY(-2px);
}
.btn-outline-neon:focus-visible { outline: 3px solid rgba(0, 229, 255, 0.4); outline-offset: 3px; }
.btn-outline-neon:active { transform: translateY(0); }
.badge-neon {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(0, 229, 255, 0.1);
  color: var(--c-primary);
  border: 1px solid rgba(0, 229, 255, 0.24);
  font-size: 12px;
  font-weight: 600;
  padding: 4px 14px;
  border-radius: 100px;
  white-space: nowrap;
}
.badge-purple {
  background: rgba(157, 78, 221, 0.14);
  color: #c084fc;
  border-color: rgba(157, 78, 221, 0.3);
}
.badge-gold {
  background: rgba(255, 204, 77, 0.1);
  color: #ffd66b;
  border-color: rgba(255, 204, 77, 0.28);
}

/* Header / Nav */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(10, 14, 23, 0.82);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  border-bottom: 1px solid var(--c-dark-line);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}
.site-header::after {
  content: "";
  display: block;
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--c-primary), var(--c-secondary), transparent);
  opacity: 0.55;
}
.navbar {
  padding-block: 0;
  min-height: 72px;
}
.navbar-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 10px 0;
}
.brand-logo-icon {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  background: var(--gradient-main);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
  font-weight: 900;
  color: #041018;
  letter-spacing: -0.02em;
  box-shadow: 0 0 20px rgba(0, 229, 255, 0.3);
}
.brand-logo-text {
  font-size: 20px;
  font-weight: 800;
  color: var(--c-white);
  letter-spacing: 0.02em;
  line-height: 1;
}
.brand-logo-text .logo-hl {
  color: var(--c-primary);
}
.site-header .navbar-nav {
  gap: 4px;
}
.site-header .nav-link {
  color: var(--c-text-weak);
  font-weight: 600;
  font-size: 15px;
  padding: 10px 18px;
  border-radius: 100px;
  transition: color .25s, background .25s, box-shadow .25s;
  position: relative;
}
.site-header .nav-link:hover {
  color: var(--c-primary);
  background: rgba(0, 229, 255, 0.07);
}
.site-header .nav-link.active {
  color: var(--c-primary);
  background: rgba(0, 229, 255, 0.1);
  box-shadow: inset 0 0 0 1px rgba(0, 229, 255, 0.2), 0 0 18px rgba(0, 229, 255, 0.12);
}
.nav-actions {
  margin-left: 16px;
  display: flex;
  align-items: center;
}
.navbar-toggler {
  border: 1px solid var(--c-border-strong);
  border-radius: 10px;
  box-shadow: none;
  padding: 8px 10px;
  color: var(--c-primary);
}
.navbar-toggler:focus { box-shadow: 0 0 0 3px rgba(0, 229, 255, 0.25); }
.navbar-toggler-icon {
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3E%3Cpath stroke='%2300e5ff' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3E%3C/svg%3E");
}
.navbar-collapse {
  gap: 12px;
}

/* Hero */
.hero-section {
  position: relative;
  min-height: 620px;
  display: flex;
  align-items: center;
  padding-block: 80px;
  background:
    linear-gradient(to bottom, rgba(10, 14, 23, 0.65), rgba(10, 14, 23, 0.92)),
    url("/assets/images/backpic/back-1.png") center/cover no-repeat;
  border-bottom: 1px solid var(--c-dark-line);
  overflow: hidden;
}
.hero-section::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--c-primary), transparent);
  opacity: 0.6;
}
.hero-content {
  max-width: 720px;
  position: relative;
  z-index: 2;
}
.hero-tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 24px;
}
.hero-pretitle {
  font-size: 15px;
  font-weight: 600;
  color: var(--c-primary);
  letter-spacing: 0.1em;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.hero-pretitle::before {
  content: "";
  width: 36px;
  height: 2px;
  background: var(--c-primary);
  box-shadow: 0 0 12px var(--c-primary);
}
.hero-title {
  font-size: clamp(38px, 6vw, 62px);
  font-weight: 900;
  line-height: 1.12;
  color: var(--c-white);
  letter-spacing: -0.02em;
  margin: 0 0 20px;
}
.hero-desc {
  font-size: 17px;
  line-height: 1.9;
  color: #aab8ca;
  margin: 0 0 32px;
  max-width: 580px;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 42px;
}
.hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 36px;
}
.hero-stat-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.hero-stat-number {
  font-size: 28px;
  font-weight: 800;
  color: var(--c-white);
  line-height: 1.2;
}
.hero-stat-label {
  font-size: 13px;
  color: var(--c-text-weak);
}
.hero-badge-area {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 8px;
}

/* Stats strip */
.stats-strip {
  padding-block: 28px;
  background: var(--c-bg-soft);
  border-bottom: 1px solid var(--c-dark-line);
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.stat-cell {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 10px 4px;
}
.stat-cell-icon {
  width: 48px;
  height: 48px;
  flex-shrink: 0;
  border-radius: 14px;
  background: var(--gradient-soft);
  border: 1px solid var(--c-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--c-primary);
  font-size: 20px;
}
.stat-cell-text { line-height: 1.35; }
.stat-cell-value {
  font-size: 20px;
  font-weight: 800;
  color: var(--c-white);
}
.stat-cell-label {
  font-size: 13px;
  color: var(--c-text-weak);
}

/* About / core */
.about-section {
  background: transparent;
}
.about-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 56px;
  align-items: center;
}
.about-visual {
  position: relative;
}
.about-img-wrap {
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--c-border);
  box-shadow: var(--shadow-lg);
  position: relative;
}
.about-img-wrap img {
  width: 100%;
  object-fit: cover;
  transition: transform .6s ease;
}
.about-img-wrap:hover img { transform: scale(1.03); }
.about-img-wrap::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(10, 14, 23, 0.35), transparent 55%);
  pointer-events: none;
}
.about-float-card {
  position: absolute;
  right: -18px;
  bottom: 30px;
  background: rgba(17, 24, 39, 0.92);
  backdrop-filter: blur(12px);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-md);
  padding: 18px 22px;
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  gap: 12px;
  max-width: 260px;
}
.about-float-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: var(--gradient-main);
  color: #041018;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
}
.about-float-text {
  line-height: 1.4;
}
.about-float-title {
  font-weight: 700;
  color: var(--c-white);
  font-size: 14px;
}
.about-float-desc {
  font-size: 12px;
  color: var(--c-text-weak);
}
.about-content {
  padding-left: 8px;
}
.about-content .section-head {
  text-align: left;
  margin: 0 0 24px;
  max-width: none;
}
.about-content .section-kicker { margin-bottom: 12px; }
.about-content .section-title { font-size: clamp(26px, 3vw, 36px); }
.about-desc {
  color: var(--c-text-weak);
  line-height: 1.9;
  margin-bottom: 20px;
}
.about-list {
  list-style: none;
  padding: 0;
  margin: 0 0 28px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px 20px;
}
.about-list li {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 15px;
  color: var(--c-text);
}
.about-list i {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: rgba(0, 229, 255, 0.12);
  color: var(--c-primary);
  font-size: 11px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.about-meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  padding-top: 24px;
  border-top: 1px solid var(--c-dark-line);
}
.about-meta-item {
  display: flex;
  align-items: center;
  gap: 12px;
}
.about-meta-icon {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: rgba(157, 78, 221, 0.12);
  border: 1px solid rgba(157, 78, 221, 0.24);
  color: #c084fc;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 17px;
}
.about-meta-text { line-height: 1.4; }
.about-meta-title { font-weight: 700; color: var(--c-white); font-size: 15px; }
.about-meta-sub { font-size: 12px; color: var(--c-text-weak); }

/* Topics / category */
.topics-section {
  background:
    linear-gradient(to bottom, rgba(13, 18, 32, 0.9), rgba(13, 18, 32, 0.96)),
    url("/assets/images/backpic/back-2.png") center/cover no-repeat;
  border-block: 1px solid var(--c-dark-line);
}
.topics-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 32px;
}
.topic-card {
  position: relative;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-sm);
  transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease;
  min-height: 320px;
}
.topic-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--c-border-strong);
}
.topic-card-img {
  position: relative;
  height: 180px;
  overflow: hidden;
  border-bottom: 1px solid var(--c-dark-line);
}
.topic-card-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform .6s ease;
}
.topic-card:hover .topic-card-img img { transform: scale(1.06); }
.topic-card-img::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(17, 24, 39, 0.8), transparent 60%);
}
.topic-card-badge {
  position: absolute;
  top: 16px;
  left: 16px;
  z-index: 2;
}
.topic-card-body {
  padding: 28px;
  display: flex;
  flex-direction: column;
  flex: 1;
}
.topic-card-title {
  font-size: 21px;
  font-weight: 800;
  color: var(--c-white);
  margin-bottom: 10px;
  line-height: 1.4;
}
.topic-card-text {
  color: var(--c-text-weak);
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 22px;
  flex: 1;
}
.topic-card-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 15px;
  color: var(--c-primary);
  margin-top: auto;
  transition: gap .3s ease, color .3s ease;
}
.topic-card-link:hover { gap: 14px; color: #52efff; }
.topic-card-link i { font-size: 13px; }
.topic-card-extra {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

/* News */
.news-section { background: transparent; }
.news-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}
.news-card {
  display: flex;
  flex-direction: column;
  background: var(--c-surface);
  border: 1px solid var(--c-dark-line);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease;
  position: relative;
  padding: 26px;
}
.news-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-main);
  opacity: 0;
  transition: opacity .3s ease;
}
.news-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--c-border);
}
.news-card:hover::before { opacity: 1; }
.news-card-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}
.news-card-cat {
  font-size: 12px;
  font-weight: 700;
  color: var(--c-primary);
  background: rgba(0, 229, 255, 0.08);
  border: 1px solid rgba(0, 229, 255, 0.18);
  padding: 4px 12px;
  border-radius: 100px;
  letter-spacing: 0.04em;
}
.news-card-idx {
  font-size: 13px;
  font-weight: 800;
  color: rgba(255, 255, 255, 0.14);
  letter-spacing: 0.05em;
}
.news-card h3 {
  font-size: 17px;
  font-weight: 700;
  line-height: 1.55;
  margin: 0 0 12px;
  color: var(--c-white);
}
.news-card h3 a {
  color: inherit;
  transition: color .25s;
}
.news-card h3 a:hover { color: var(--c-primary); }
.news-card-desc {
  font-size: 14px;
  color: var(--c-text-weak);
  line-height: 1.75;
  margin-bottom: 20px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  flex: 1;
}
.news-card-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 16px;
  border-top: 1px solid var(--c-dark-line);
  margin-top: auto;
}
.news-card-date {
  font-size: 13px;
  color: var(--c-text-faint);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.news-card-more {
  font-size: 14px;
  font-weight: 700;
  color: var(--c-primary);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: gap .25s ease;
}
.news-card-more:hover { gap: 10px; color: #52efff; }
.empty-tip {
  grid-column: 1 / -1;
  text-align: center;
  padding: 50px 20px;
  background: var(--c-surface);
  border: 1px dashed var(--c-border);
  border-radius: var(--radius-lg);
  color: var(--c-text-weak);
  font-size: 15px;
}

/* Steps */
.steps-section {
  background:
    linear-gradient(to bottom, rgba(13, 18, 32, 0.94), rgba(13, 18, 32, 0.98)),
    url("/assets/images/backpic/back-3.png") center/cover no-repeat;
  border-block: 1px solid var(--c-dark-line);
}
.steps-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 28px;
  position: relative;
}
.steps-grid::before {
  content: "";
  position: absolute;
  top: 60px;
  left: 12%;
  right: 12%;
  height: 2px;
  background: linear-gradient(90deg, var(--c-primary), var(--c-secondary), var(--c-primary));
  opacity: 0.25;
  border-radius: 2px;
}
.step-card {
  position: relative;
  text-align: center;
  padding: 30px 18px 24px;
  background: rgba(17, 24, 39, 0.72);
  backdrop-filter: blur(8px);
  border: 1px solid var(--c-dark-line);
  border-radius: var(--radius-md);
  transition: transform .3s ease, border-color .3s ease, box-shadow .3s ease;
  z-index: 2;
}
.step-card:hover {
  transform: translateY(-6px);
  border-color: var(--c-border);
  box-shadow: var(--shadow-md);
}
.step-icon {
  width: 60px;
  height: 60px;
  margin: 0 auto 18px;
  border-radius: 18px;
  background: var(--gradient-main);
  color: #041018;
  font-size: 22px;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 22px rgba(0, 229, 255, 0.25);
}
.step-num {
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.14em;
  color: var(--c-primary);
  margin-bottom: 6px;
  display: block;
}
.step-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--c-white);
  margin-bottom: 8px;
}
.step-text {
  font-size: 14px;
  color: var(--c-text-weak);
  line-height: 1.7;
}

/* Features */
.features-section { background: transparent; }
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}
.feature-card {
  padding: 32px 28px;
  background: var(--c-surface);
  border: 1px solid var(--c-dark-line);
  border-radius: var(--radius-md);
  transition: transform .3s ease, box-shadow .3s ease, border-color .3s ease;
}
.feature-card:hover {
  transform: translateY(-6px);
  border-color: var(--c-border);
  box-shadow: var(--shadow-lg);
}
.feature-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: var(--gradient-soft);
  border: 1px solid var(--c-border);
  color: var(--c-primary);
  font-size: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  transition: background .3s ease, color .3s ease;
}
.feature-card:hover .feature-icon {
  background: var(--gradient-main);
  color: #041018;
}
.feature-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--c-white);
  margin-bottom: 10px;
}
.feature-text {
  font-size: 14px;
  color: var(--c-text-weak);
  line-height: 1.75;
  margin: 0;
}

/* FAQ */
.faq-section {
  background: var(--c-bg-soft);
  border-block: 1px solid var(--c-dark-line);
}
.faq-list {
  max-width: 860px;
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.faq-item {
  background: var(--c-surface);
  border: 1px solid var(--c-dark-line);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color .3s ease, box-shadow .3s ease;
}
.faq-item:focus-within,
.faq-item:hover {
  border-color: var(--c-border);
  box-shadow: var(--shadow-sm);
}
.faq-item.open { border-color: var(--c-border-strong); }
.faq-question {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 22px 26px;
  background: transparent;
  border: none;
  color: var(--c-white);
  font-size: 16px;
  font-weight: 700;
  text-align: left;
  cursor: pointer;
  transition: color .25s;
}
.faq-question:hover { color: var(--c-primary); }
.faq-question:focus-visible { outline: 3px solid rgba(0, 229, 255, 0.4); outline-offset: -2px; }
.faq-icon {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: rgba(0, 229, 255, 0.1);
  border: 1px solid rgba(0, 229, 255, 0.2);
  color: var(--c-primary);
  font-size: 13px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: transform .3s ease, background .3s ease;
}
.faq-item.open .faq-icon {
  transform: rotate(45deg);
  background: var(--gradient-main);
  color: #041018;
}
.faq-answer {
  padding: 0 26px 22px;
  color: var(--c-text-weak);
  font-size: 15px;
  line-height: 1.85;
  display: none;
}
.faq-item.open .faq-answer { display: block; }

/* CTA */
.cta-section {
  padding-block: 90px;
  position: relative;
  overflow: hidden;
}
.cta-inner {
  position: relative;
  background: var(--gradient-soft);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-xl);
  padding: 64px 48px;
  text-align: center;
  box-shadow: var(--shadow-md);
  overflow: hidden;
}
.cta-inner::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at 15% 20%, rgba(0, 229, 255, 0.2), transparent 50%),
    radial-gradient(ellipse at 85% 80%, rgba(157, 78, 221, 0.2), transparent 45%);
  pointer-events: none;
}
.cta-inner>* { position: relative; z-index: 2; }
.cta-title {
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 800;
  color: var(--c-white);
  line-height: 1.3;
  margin-bottom: 16px;
}
.cta-text {
  font-size: 16px;
  color: var(--c-text-weak);
  max-width: 520px;
  margin: 0 auto 30px;
  line-height: 1.8;
}
.cta-actions {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 14px;
}

/* Footer */
.site-footer {
  background: #070b13;
  border-top: 1px solid var(--c-dark-line);
  padding-top: 56px;
}
.site-footer::before {
  content: "";
  display: block;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(0, 229, 255, 0.4), transparent);
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 44px;
}
.footer-brand .brand-logo-text { font-size: 20px; }
.footer-desc {
  font-size: 14px;
  color: var(--c-text-weak);
  line-height: 1.8;
  margin: 18px 0 22px;
  max-width: 320px;
}
.footer-social {
  display: flex;
  gap: 10px;
}
.footer-social a {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--c-dark-line);
  color: var(--c-text-weak);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
  transition: all .25s ease;
}
.footer-social a:hover {
  color: var(--c-primary);
  border-color: var(--c-border);
  background: rgba(0, 229, 255, 0.08);
  transform: translateY(-3px);
}
.footer-heading {
  font-size: 15px;
  font-weight: 800;
  color: var(--c-white);
  margin: 0 0 18px;
  letter-spacing: 0.05em;
}
.footer-links {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.footer-links a {
  color: var(--c-text-weak);
  font-size: 14px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: color .25s, gap .25s;
}
.footer-links a:hover {
  color: var(--c-primary);
  gap: 13px;
}
.footer-links i {
  font-size: 11px;
  color: var(--c-primary);
}
.footer-bottom {
  border-top: 1px solid var(--c-dark-line);
  padding-block: 22px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 13px;
  color: var(--c-text-faint);
}
.footer-bottom a { color: var(--c-text-faint); }
.footer-bottom a:hover { color: var(--c-primary); }

/* Responsive */
@media (max-width: 1024px) {
  :root { --space-section: 80px; }
  .about-grid { gap: 40px; }
  .steps-grid { gap: 20px; }
  .news-grid { grid-template-columns: repeat(2, 1fr); }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  :root { --space-section: 64px; }
  .site-header .navbar-collapse {
    background: rgba(10, 14, 23, 0.98);
    border-radius: var(--radius-md);
    border: 1px solid var(--c-dark-line);
    padding: 16px;
    margin-top: 10px;
  }
  .site-header .navbar-nav { gap: 2px; }
  .site-header .nav-link {
    padding: 12px 16px;
    border-radius: 10px;
  }
  .nav-actions { margin-left: 0; margin-top: 10px; padding-top: 10px; border-top: 1px solid var(--c-dark-line); }
  .about-grid { grid-template-columns: 1fr; }
  .about-content { padding-left: 0; }
  .about-list { grid-template-columns: 1fr; }
  .topics-grid { grid-template-columns: 1fr; }
  .steps-grid { grid-template-columns: repeat(2, 1fr); }
  .steps-grid::before { display: none; }
  .hero-section { min-height: 540px; padding-block: 60px; }
  .hero-actions { gap: 12px; }
  .hero-stats { gap: 24px; }
  .cta-inner { padding: 44px 24px; }
}
@media (max-width: 520px) {
  :root { --space-section: 52px; }
  .container-custom { width: 92%; }
  .news-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr; }
  .steps-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
  .stat-cell { gap: 12px; }
  .stat-cell-icon { width: 42px; height: 42px; font-size: 17px; }
  .stat-cell-value { font-size: 18px; }
  .stat-cell-label { font-size: 12px; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .footer-bottom { flex-direction: column; text-align: center; }
  .hero-title { font-size: 34px; }
  .hero-desc { font-size: 15px; }
  .about-float-card { right: 10px; bottom: 16px; max-width: 220px; }
  .section-title { font-size: 25px; }
  .faq-question { padding: 18px 18px; font-size: 15px; }
  .faq-answer { padding: 0 18px 18px; }
  .cta-inner { padding: 36px 18px; border-radius: var(--radius-lg); }
  .brand-logo-text { font-size: 18px; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; scroll-behavior: auto !important; }
}

/* roulang page: article */
:root {
    --primary: #00e5ff;
    --primary-glow: rgba(0, 229, 255, 0.35);
    --secondary: #ff3d81;
    --secondary-glow: rgba(255, 61, 129, 0.35);
    --accent-purple: #b44dff;
    --bg-dark: #0a0e17;
    --bg-panel: #101624;
    --bg-card: #161f33;
    --bg-card-hover: #1b2740;
    --text-light: #f0f6ff;
    --text-muted: #8b9bb4;
    --border: rgba(255, 255, 255, 0.08);
    --border-glow: rgba(0, 229, 255, 0.2);
    --radius: 16px;
    --radius-sm: 10px;
    --shadow: 0 8px 30px rgba(0, 0, 0, 0.35);
    --shadow-neon: 0 0 25px rgba(0, 229, 255, 0.15);
    --transition: all 0.3s ease;
    --spacing-section: 80px;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', 'HarmonyOS Sans', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    background: var(--bg-dark);
    color: var(--text-light);
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

button,
input,
select {
    font-family: inherit;
    outline: none;
}

ul,
ol {
    list-style: none;
}

::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-dark);
}

::-webkit-scrollbar-thumb {
    background: #1e2a45;
    border-radius: 8px;
}

::-webkit-scrollbar-thumb:hover {
    background: #2b3b5e;
}

.container,
.container-custom {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.section-label {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    letter-spacing: 1px;
    color: var(--primary);
    text-transform: uppercase;
    margin-bottom: 10px;
    font-weight: 600;
}

.section-title {
    font-size: clamp(1.5rem, 3vw, 2rem);
    font-weight: 800;
    line-height: 1.4;
    margin-bottom: 12px;
    color: var(--text-light);
}

.section-sub {
    color: var(--text-muted);
    margin-bottom: 34px;
    max-width: 640px;
    font-size: 15px;
}

/* ===== Header / Nav ===== */
.site-header {
    position: sticky;
    top: 0;
    z-index: 1030;
    background: rgba(10, 14, 23, 0.88);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
}

.navbar {
    min-height: 72px;
    padding: 10px 0;
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 0;
}

.brand-logo-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 42px;
    height: 42px;
    border-radius: 12px;
    background: linear-gradient(135deg, var(--primary), var(--accent-purple));
    color: #08111f;
    font-weight: 800;
    font-size: 16px;
    letter-spacing: .5px;
    box-shadow: 0 0 18px var(--primary-glow);
}

.brand-logo-text {
    font-size: 20px;
    font-weight: 800;
    color: var(--text-light);
    line-height: 1;
}

.logo-hl {
    color: var(--primary);
    text-shadow: 0 0 14px var(--primary-glow);
}

.navbar .nav-link {
    color: rgba(240, 246, 255, 0.75);
    font-weight: 500;
    font-size: 15px;
    padding: 10px 14px !important;
    border-radius: 8px;
    margin: 0 4px;
    position: relative;
    transition: var(--transition);
}

.navbar .nav-link:hover {
    color: var(--primary);
}

.navbar .nav-link.active {
    color: var(--primary);
    text-shadow: 0 0 10px var(--primary-glow);
}

.navbar .nav-link.active::after {
    content: '';
    position: absolute;
    left: 14px;
    right: 14px;
    bottom: 4px;
    height: 2px;
    background: var(--primary);
    border-radius: 2px;
    box-shadow: 0 0 10px var(--primary-glow);
}

.nav-actions {
    margin-left: 18px;
    display: flex;
    align-items: center;
}

.navbar-toggler {
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 10px;
    padding: 6px 10px;
    transition: var(--transition);
}

.navbar-toggler:focus {
    box-shadow: 0 0 0 3px rgba(0, 229, 255, 0.15);
}

.navbar-toggler-icon {
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='rgba%28255,255,255,0.85%29' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
}

.btn-neon {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 11px 26px;
    border-radius: 999px;
    font-weight: 600;
    font-size: 15px;
    color: #08111f;
    background: linear-gradient(135deg, var(--primary), #00c6ea);
    border: 0;
    transition: var(--transition);
    box-shadow: 0 0 20px var(--primary-glow);
    cursor: pointer;
}

.btn-neon:hover {
    color: #08111f;
    transform: translateY(-2px);
    box-shadow: 0 0 32px var(--primary-glow);
}

.btn-neon:active {
    transform: translateY(0);
    box-shadow: 0 0 12px var(--primary-glow);
}

.btn-neon:focus-visible,
.btn-outline-neon:focus-visible,
.nav-link:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
}

.btn-outline-neon {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 26px;
    border-radius: 999px;
    font-weight: 600;
    font-size: 15px;
    color: var(--primary);
    background: transparent;
    border: 1px solid rgba(0, 229, 255, 0.45);
    transition: var(--transition);
    cursor: pointer;
}

.btn-outline-neon:hover {
    background: rgba(0, 229, 255, 0.1);
    color: var(--primary);
    transform: translateY(-2px);
}

.btn-outline-neon:active {
    transform: translateY(0);
    background: rgba(0, 229, 255, 0.16);
}

.btn-lg {
    padding: 13px 34px;
    font-size: 16px;
}

/* ===== Article Hero ===== */
.article-hero {
    position: relative;
    padding: 130px 0 90px;
    background-size: cover;
    background-position: center;
    background-color: var(--bg-dark);
}

.article-hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(10, 14, 23, 0.94) 0%, rgba(10, 14, 23, 0.78) 55%, rgba(0, 229, 255, 0.14) 100%);
}

.article-hero::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(0, 229, 255, 0.5), transparent);
}

.article-hero .container-custom {
    position: relative;
    z-index: 2;
}

.breadcrumb-wrap {
    margin-bottom: 18px;
}

.breadcrumb {
    margin-bottom: 0;
    padding: 0;
    background: transparent;
}

.breadcrumb-item a {
    color: rgba(240, 246, 255, 0.6);
    font-size: 14px;
    transition: var(--transition);
}

.breadcrumb-item a:hover {
    color: var(--primary);
}

.breadcrumb-item.active {
    color: var(--primary);
    font-size: 14px;
}

.breadcrumb-item + .breadcrumb-item::before {
    color: rgba(255, 255, 255, 0.3);
    padding-right: 0.6rem;
    padding-left: 0.4rem;
}

.hero-tag {
    display: inline-block;
    padding: 6px 16px;
    font-size: 13px;
    letter-spacing: .5px;
    color: var(--primary);
    background: rgba(0, 229, 255, 0.1);
    border: 1px solid rgba(0, 229, 255, 0.3);
    border-radius: 999px;
    margin-bottom: 16px;
}

.article-hero-title {
    font-size: clamp(1.8rem, 4vw, 2.8rem);
    font-weight: 800;
    line-height: 1.3;
    margin: 0 0 18px;
    text-shadow: 0 0 30px rgba(0, 229, 255, 0.2);
}

.article-meta-line {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 24px;
    font-size: 14px;
    color: var(--text-muted);
}

.meta-item {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.meta-item i {
    color: var(--primary);
}

/* ===== Article Layout ===== */
.article-section {
    padding: 70px 0;
}

.article-layout {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 340px;
    gap: 40px;
    align-items: start;
}

.article-main {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 38px 40px;
    box-shadow: var(--shadow);
    min-width: 0;
}

.article-abstract {
    padding: 18px 20px;
    border-left: 3px solid var(--primary);
    background: rgba(0, 229, 255, 0.06);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    margin-bottom: 30px;
    font-size: 15px;
    color: rgba(240, 246, 255, 0.82);
    line-height: 1.8;
}

.article-content {
    font-size: 16px;
    line-height: 1.9;
    color: rgba(240, 246, 255, 0.88);
    word-wrap: break-word;
}

.article-content h2 {
    font-size: 1.6rem;
    font-weight: 700;
    margin: 34px 0 16px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border);
    color: var(--text-light);
}

.article-content h3 {
    font-size: 1.3rem;
    font-weight: 700;
    margin: 26px 0 12px;
    color: var(--primary);
}

.article-content p {
    margin-bottom: 18px;
}

.article-content ul {
    margin-bottom: 18px;
    padding-left: 0;
}

.article-content ul li {
    position: relative;
    padding-left: 24px;
    margin-bottom: 8px;
}

.article-content ul li::before {
    content: '▸';
    position: absolute;
    left: 6px;
    color: var(--primary);
    font-size: 18px;
    line-height: 1.4;
}

.article-content ol {
    margin-bottom: 18px;
    padding-left: 22px;
}

.article-content img {
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    margin: 20px 0;
    max-width: 100%;
}

.article-content blockquote {
    border-left: 3px solid var(--secondary);
    background: rgba(255, 61, 129, 0.06);
    padding: 16px 20px;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    margin: 24px 0;
    color: var(--text-muted);
}

.article-content a {
    color: var(--primary);
    border-bottom: 1px dashed rgba(0, 229, 255, 0.5);
}

.article-content a:hover {
    color: var(--text-light);
    border-bottom-color: var(--text-light);
}

.article-content code {
    background: rgba(255, 255, 255, 0.08);
    padding: 2px 8px;
    border-radius: 6px;
    font-size: 0.92em;
    color: var(--primary);
}

.article-tags {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 10px;
    margin-top: 34px;
    padding-top: 24px;
    border-top: 1px solid var(--border);
    font-size: 14px;
    color: var(--text-muted);
}

.tag-item {
    display: inline-block;
    padding: 5px 14px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border);
    border-radius: 999px;
    font-size: 13px;
    color: var(--text-muted);
    transition: var(--transition);
}

.tag-item:hover {
    color: var(--primary);
    border-color: rgba(0, 229, 255, 0.4);
    background: rgba(0, 229, 255, 0.08);
}

/* ===== Sidebar ===== */
.article-side {
    min-width: 0;
}

.side-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 26px;
    margin-bottom: 24px;
    box-shadow: var(--shadow);
}

.side-cover {
    position: relative;
    margin: -26px -26px 18px;
    border-radius: var(--radius) var(--radius) 0 0;
    overflow: hidden;
}

.side-cover img {
    width: 100%;
    height: 135px;
    object-fit: cover;
}

.side-cover::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(10, 14, 23, 0.6), transparent);
}

.side-badge {
    position: absolute;
    left: 16px;
    bottom: 12px;
    z-index: 2;
    background: linear-gradient(135deg, var(--primary), var(--accent-purple));
    color: #08111f;
    font-weight: 800;
    font-size: 18px;
    padding: 2px 14px;
    border-radius: 8px;
    letter-spacing: 0.3px;
    box-shadow: 0 0 14px rgba(0, 229, 255, 0.3);
}

.side-about h3 {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--text-light);
}

.side-about p {
    font-size: 14px;
    line-height: 1.75;
    color: var(--text-muted);
    margin-bottom: 14px;
}

.side-more {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    color: var(--primary);
    font-weight: 600;
}

.side-more:hover {
    color: var(--text-light);
    gap: 10px;
}

.side-title {
    font-size: 1rem;
    font-weight: 700;
    color: var(--text-light);
    margin-bottom: 18px;
    display: flex;
    align-items: center;
    gap: 8px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border);
}

.side-title i {
    color: var(--primary);
}

.side-list li {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    padding: 10px 0;
    border-bottom: 1px dashed rgba(255, 255, 255, 0.06);
}

.side-list li:last-child {
    border-bottom: 0;
}

.side-list a {
    display: flex;
    flex-direction: column;
    gap: 4px;
    font-size: 14px;
    color: rgba(240, 246, 255, 0.85);
    line-height: 1.5;
    transition: var(--transition);
    min-width: 0;
}

.side-list a:hover {
    color: var(--primary);
}

.side-list small {
    font-size: 12px;
    color: var(--text-muted);
}

.side-list-dot {
    width: 6px;
    height: 6px;
    background: var(--primary);
    border-radius: 50%;
    margin-top: 8px;
    box-shadow: 0 0 8px var(--primary-glow);
    flex-shrink: 0;
}

/* ===== Not Found ===== */
.not-found-card {
    max-width: 620px;
    margin: 0 auto;
    text-align: center;
    padding: 70px 40px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.not-found-card i {
    font-size: 54px;
    color: var(--primary);
    margin-bottom: 18px;
    display: inline-block;
    text-shadow: 0 0 24px var(--primary-glow);
}

.not-found-card h2 {
    font-size: 1.8rem;
    font-weight: 800;
    margin-bottom: 12px;
}

.not-found-card p {
    color: var(--text-muted);
    margin-bottom: 24px;
}

/* ===== Keypoints ===== */
.keypoints-section {
    padding: var(--spacing-section) 0;
    background: var(--bg-panel);
    border-top: 1px solid var(--border);
}

.keypoints-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 22px;
}

.keypoint-card {
    position: relative;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 24px;
    transition: var(--transition);
    overflow: hidden;
}

.keypoint-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--primary), transparent);
    opacity: 0;
    transition: var(--transition);
}

.keypoint-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-neon);
    border-color: rgba(0, 229, 255, 0.2);
}

.keypoint-card:hover::before {
    opacity: 1;
}

.keypoint-icon {
    width: 52px;
    height: 52px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 14px;
    background: rgba(0, 229, 255, 0.1);
    color: var(--primary);
    font-size: 22px;
    margin-bottom: 18px;
    border: 1px solid var(--border-glow);
    transition: var(--transition);
}

.keypoint-card:hover .keypoint-icon {
    box-shadow: 0 0 18px var(--primary-glow);
    transform: scale(1.05);
}

.keypoint-card h3 {
    font-size: 1.05rem;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-light);
}

.keypoint-card p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 0;
}

/* ===== Category Cards ===== */
.category-section {
    padding: var(--spacing-section) 0;
}

.category-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.category-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: var(--transition);
    display: block;
}

.category-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-neon);
    border-color: rgba(0, 229, 255, 0.25);
}

.category-card img {
    width: 100%;
    height: 190px;
    object-fit: cover;
    border-bottom: 1px solid var(--border);
    transition: transform 0.4s ease;
}

.category-card:hover img {
    transform: scale(1.03);
}

.category-info {
    padding: 22px;
}

.category-info h3 {
    font-size: 1.08rem;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-light);
}

.category-info p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 14px;
}

.category-more {
    font-size: 13px;
    color: var(--primary);
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-weight: 600;
}

.category-card:hover .category-more {
    gap: 8px;
}

/* ===== News List ===== */
.news-section {
    padding: var(--spacing-section) 0;
    background: var(--bg-panel);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.news-list {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 18px;
}

.news-item {
    display: flex;
    gap: 14px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 16px;
    transition: var(--transition);
    align-items: flex-start;
}

.news-item:hover {
    border-color: rgba(0, 229, 255, 0.3);
    box-shadow: var(--shadow);
    transform: translateY(-3px);
}

.news-thumb {
    width: 120px;
    height: 86px;
    object-fit: cover;
    border-radius: 8px;
    flex-shrink: 0;
    border: 1px solid var(--border);
}

.news-body {
    min-width: 0;
    flex: 1;
}

.news-body h3 {
    font-size: 15px;
    font-weight: 600;
    line-height: 1.5;
    margin-bottom: 8px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.news-body h3 a {
    color: var(--text-light);
    transition: var(--transition);
}

.news-body h3 a:hover {
    color: var(--primary);
}

.news-info {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 12px;
    color: var(--text-muted);
    flex-wrap: wrap;
}

.badge-cat {
    display: inline-block;
    padding: 2px 10px;
    border-radius: 999px;
    background: rgba(0, 229, 255, 0.12);
    color: var(--primary);
    font-size: 12px;
    border: 1px solid rgba(0, 229, 255, 0.15);
}

/* ===== FAQ ===== */
.faq-section {
    padding: var(--spacing-section) 0;
}

.faq-grid {
    max-width: 860px;
    margin: 0 auto;
}

.accordion-item {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm) !important;
    margin-bottom: 14px;
    overflow: hidden;
}

.accordion-button {
    background: transparent;
    color: var(--text-light);
    font-weight: 600;
    font-size: 15px;
    padding: 18px 22px;
    box-shadow: none;
    transition: var(--transition);
}

.accordion-button:not(.collapsed) {
    background: rgba(0, 229, 255, 0.07);
    color: var(--primary);
}

.accordion-button:focus {
    box-shadow: 0 0 0 3px rgba(0, 229, 255, 0.12);
}

.accordion-button::after {
    filter: brightness(0) invert(1);
    opacity: 0.7;
    transition: var(--transition);
}

.accordion-button:not(.collapsed)::after {
    filter: brightness(0) invert(1) hue-rotate(180deg);
    opacity: 1;
}

.accordion-body {
    color: var(--text-muted);
    font-size: 14px;
    line-height: 1.8;
    padding: 6px 22px 22px;
    background: transparent;
    border-top: 1px solid var(--border);
}

/* ===== CTA ===== */
.cta-section {
    padding: 0 0 var(--spacing-section);
}

.cta-wrapper {
    position: relative;
    border-radius: 20px;
    padding: 56px 48px;
    overflow: hidden;
    background: url('/assets/images/backpic/back-2.png') center/cover no-repeat;
    border: 1px solid var(--border-glow);
    box-shadow: var(--shadow);
}

.cta-wrapper::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(10, 14, 23, 0.94), rgba(22, 27, 47, 0.82));
}

.cta-inner {
    position: relative;
    z-index: 2;
    text-align: center;
}

.cta-inner h2 {
    font-size: clamp(1.5rem, 3vw, 2.2rem);
    font-weight: 800;
    margin-bottom: 12px;
    color: var(--text-light);
}

.cta-inner p {
    max-width: 600px;
    margin: 0 auto 28px;
    color: var(--text-muted);
    font-size: 15px;
}

.cta-buttons {
    display: flex;
    gap: 14px;
    justify-content: center;
    flex-wrap: wrap;
}

/* ===== Footer ===== */
.site-footer {
    background: #070b12;
    border-top: 1px solid var(--border);
    padding: 60px 0 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.8fr 1fr 1fr;
    gap: 40px;
    padding-bottom: 42px;
}

.footer-brand .navbar-brand {
    padding: 0;
}

.footer-desc {
    color: var(--text-muted);
    font-size: 14px;
    line-height: 1.8;
    margin: 18px 0 20px;
    max-width: 380px;
}

.footer-social {
    display: flex;
    gap: 12px;
}

.footer-social a {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border);
    color: var(--text-muted);
    transition: var(--transition);
}

.footer-social a:hover {
    color: var(--primary);
    border-color: rgba(0, 229, 255, 0.4);
    box-shadow: 0 0 14px rgba(0, 229, 255, 0.15);
    transform: translateY(-3px);
}

.footer-heading {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 18px;
    color: var(--text-light);
}

.footer-links li {
    margin-bottom: 10px;
}

.footer-links a {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    color: var(--text-muted);
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--primary);
    padding-left: 4px;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    padding: 22px 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
    font-size: 13px;
    color: var(--text-muted);
    flex-wrap: wrap;
}

/* ===== Responsive ===== */
@media (max-width: 991px) {
    .navbar-collapse {
        padding: 16px 0 6px;
    }

    .navbar .nav-link {
        margin: 4px 0;
    }

    .nav-actions {
        margin-left: 0;
        margin-top: 14px;
        padding-top: 14px;
        border-top: 1px solid var(--border);
    }

    .article-layout {
        grid-template-columns: 1fr;
    }

    .keypoints-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .category-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .news-list {
        grid-template-columns: 1fr;
    }

    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 767px) {
    :root {
        --spacing-section: 56px;
    }

    .article-hero {
        padding: 110px 0 60px;
    }

    .article-main {
        padding: 24px 20px;
    }

    .article-layout {
        gap: 28px;
    }

    .keypoints-grid {
        grid-template-columns: 1fr 1fr;
        gap: 16px;
    }

    .category-grid {
        grid-template-columns: 1fr;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 28px;
    }

    .cta-wrapper {
        padding: 40px 22px;
    }

    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }

    .keypoints-section,
    .category-section,
    .news-section,
    .faq-section,
    .cta-section {
        padding-top: 56px;
        padding-bottom: 56px;
    }

    .news-item {
        flex-direction: row;
    }

    .news-thumb {
        width: 100px;
        height: 80px;
    }
}

@media (max-width: 575px) {
    .container,
    .container-custom {
        padding: 0 16px;
    }

    .keypoints-grid {
        grid-template-columns: 1fr;
    }

    .article-meta-line {
        gap: 8px 16px;
    }

    .news-item {
        flex-direction: column;
    }

    .news-thumb {
        width: 100%;
        height: 160px;
    }

    .footer-bottom {
        flex-direction: column;
        justify-content: center;
        text-align: center;
    }

    .not-found-card {
        padding: 50px 24px;
    }

    .accordion-button {
        font-size: 14px;
        padding: 16px 18px;
    }

    .accordion-body {
        padding: 4px 18px 18px;
    }

    .brand-logo-text {
        font-size: 18px;
    }

    .brand-logo-icon {
        width: 38px;
        height: 38px;
        font-size: 14px;
    }
}

@media (min-width: 1200px) {
    .article-hero {
        padding-top: 150px;
    }
}

/* roulang page: category1 */
:root {
    --bg-body: #080c14;
    --bg-deep: #0d1322;
    --bg-panel: #111a2c;
    --bg-card: rgba(17, 26, 44, 0.82);
    --border: rgba(0, 229, 255, 0.18);
    --border-light: rgba(255, 255, 255, 0.08);
    --text-main: #eaf2ff;
    --text-muted: #93a4c2;
    --text-weak: #61718f;
    --primary: #00e5ff;
    --secondary: #7c4dff;
    --accent: #ff3e9d;
    --success: #2dd4a7;
    --warning: #ffc857;
    --gradient-brand: linear-gradient(135deg, #00e5ff 0%, #7c4dff 100%);
    --shadow-card: 0 18px 40px rgba(0, 0, 0, 0.45);
    --shadow-neon: 0 0 24px rgba(0, 229, 255, 0.22);
    --radius-lg: 22px;
    --radius-md: 14px;
    --radius-sm: 10px;
    --container: 1200px;
    --spacer: 96px;
    --font-family: "Inter", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
    --bs-body-font-family: var(--font-family);
    --bs-body-bg: var(--bg-body);
    --bs-body-color: var(--text-main);
    --bs-border-radius: 14px;
    --bs-border-radius-lg: 22px;
    --bs-border-radius-sm: 10px;
  }

  * {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
  }

  html {
    scroll-behavior: smooth;
  }

  body {
    font-family: var(--font-family);
    background: var(--bg-body);
    color: var(--text-main);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
  }

  a {
    color: var(--primary);
    text-decoration: none;
    transition: color .25s ease;
  }

  a:hover {
    color: #ffffff;
  }

  img {
    max-width: 100%;
    display: block;
  }

  ul {
    list-style: none;
  }

  .container-custom {
    width: min(var(--container), 92%);
    margin-inline: auto;
  }

  .section {
    padding-block: 88px;
  }

  .section-head {
    max-width: 780px;
    margin-bottom: 52px;
  }

  .section-head.center {
    margin-inline: auto;
    text-align: center;
  }

  .section-head.center .section-desc {
    margin-inline: auto;
  }

  .section-label {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    color: var(--primary);
    letter-spacing: 2px;
    font-size: 13px;
    text-transform: uppercase;
  }

  .section-label::before {
    content: "";
    width: 26px;
    height: 2px;
    background: var(--primary);
    box-shadow: 0 0 8px var(--primary);
  }

  .section-title {
    font-size: clamp(1.8rem, 3vw, 2.6rem);
    font-weight: 800;
    line-height: 1.3;
    margin: 14px 0 18px;
  }

  .section-desc {
    color: var(--text-muted);
    max-width: 660px;
    font-size: 16px;
  }

  .btn-neon {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 24px;
    border-radius: 999px;
    background: var(--gradient-brand);
    color: #07111f;
    font-weight: 700;
    font-size: 15px;
    border: none;
    box-shadow: 0 0 18px rgba(0, 229, 255, 0.25);
    transition: transform .25s ease, box-shadow .25s ease;
  }

  .btn-neon:hover {
    color: #04101f;
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(124, 77, 255, 0.38);
  }

  .btn-outline {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 26px;
    border-radius: 999px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: #ffffff;
    background: transparent;
    font-weight: 600;
    transition: border-color .3s, background .3s, transform .3s;
  }

  .btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: rgba(0, 229, 255, 0.05);
    transform: translateY(-2px);
  }

  .site-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(8, 12, 20, 0.85);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--border);
  }

  .site-header .navbar {
    padding-block: 14px;
  }

  .navbar-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 0;
  }

  .brand-logo-icon {
    display: grid;
    place-items: center;
    width: 42px;
    height: 42px;
    border-radius: 12px;
    background: var(--gradient-brand);
    color: #04101f;
    font-weight: 800;
    font-size: 16px;
    letter-spacing: -1px;
    box-shadow: var(--shadow-neon);
  }

  .brand-logo-text {
    font-size: 20px;
    font-weight: 700;
    color: #ffffff;
    letter-spacing: .5px;
  }

  .logo-hl {
    color: var(--primary);
  }

  .navbar-nav .nav-link {
    color: var(--text-muted);
    font-weight: 600;
    font-size: 15px;
    padding: 10px 18px !important;
    border-radius: 10px;
    position: relative;
    transition: color .3s, background .3s;
  }

  .navbar-nav .nav-link:hover {
    color: #ffffff;
    background: rgba(0, 229, 255, 0.06);
  }

  .navbar-nav .nav-link.active {
    color: var(--primary);
    text-shadow: 0 0 12px rgba(0, 229, 255, 0.5);
  }

  .navbar-nav .nav-link.active::after {
    content: "";
    position: absolute;
    left: 18px;
    right: 18px;
    bottom: 2px;
    height: 2px;
    border-radius: 2px;
    background: var(--primary);
    box-shadow: 0 0 12px var(--primary);
  }

  .nav-actions {
    margin-left: 18px;
    display: flex;
    gap: 10px;
    align-items: center;
  }

  .navbar-toggler {
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 8px 12px;
  }

  .navbar-toggler:focus {
    box-shadow: 0 0 0 3px rgba(0, 229, 255, 0.25);
  }

  .navbar-toggler-icon {
    background-image: none !important;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .navbar-toggler-icon::before {
    content: "\f0c9";
    font-family: "Font Awesome 6 Free";
    font-weight: 900;
    color: var(--primary);
    font-size: 20px;
  }

  .page-hero {
    position: relative;
    padding: 110px 0 90px;
    background: linear-gradient(180deg, rgba(8, 12, 20, 0.9) 0%, rgba(12, 18, 34, 0.74) 60%, #080c14 100%), url('/assets/images/backpic/back-2.png') center / cover no-repeat;
    border-bottom: 1px solid var(--border);
  }

  .hero-breadcrumb {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-muted);
    font-size: 14px;
    margin-bottom: 24px;
  }

  .hero-breadcrumb a {
    color: var(--text-muted);
  }

  .hero-breadcrumb a:hover {
    color: var(--primary);
  }

  .breadcrumb-sep {
    color: var(--text-weak);
  }

  .hero-title {
    font-size: clamp(2.2rem, 4vw, 3.7rem);
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 20px;
    color: #ffffff;
  }

  .text-gradient {
    background: linear-gradient(90deg, #00e5ff, #a78bfa);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
  }

  .hero-subtitle {
    max-width: 760px;
    color: var(--text-muted);
    font-size: 18px;
    margin-bottom: 28px;
  }

  .search-wrap {
    display: flex;
    align-items: center;
    gap: 10px;
    max-width: 680px;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 999px;
    padding: 8px 10px 8px 18px;
    margin-bottom: 26px;
    backdrop-filter: blur(10px);
    transition: border-color .3s, box-shadow .3s;
  }

  .search-wrap:focus-within {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(0, 229, 255, 0.12), 0 0 24px rgba(0, 229, 255, 0.12);
  }

  .search-icon {
    color: var(--primary);
  }

  .search-input {
    flex: 1;
    background: transparent;
    border: none;
    color: #ffffff;
    font-size: 15px;
    padding: 10px 4px;
    outline: none;
  }

  .search-input::placeholder {
    color: var(--text-weak);
  }

  .search-wrap .btn-neon {
    flex-shrink: 0;
  }

  .hero-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
  }

  .badge-neon {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    border: 1px solid var(--border);
    background: rgba(0, 229, 255, 0.08);
    color: #b4f8ff;
    padding: 7px 16px;
    border-radius: 999px;
    font-size: 13px;
    transition: border-color .3s, background .3s, color .3s;
  }

  .badge-neon:hover {
    border-color: var(--primary);
    background: rgba(0, 229, 255, 0.16);
    color: #ffffff;
  }

  .guide-intro {
    background: var(--bg-body);
  }

  .intro-list {
    margin-top: 8px;
  }

  .intro-list li {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 13px 0;
    border-bottom: 1px solid var(--border-light);
    color: var(--text-muted);
    font-size: 15px;
  }

  .intro-list li:last-child {
    border-bottom: none;
  }

  .list-icon {
    width: 34px;
    height: 34px;
    display: grid;
    place-items: center;
    border-radius: 10px;
    background: rgba(0, 229, 255, 0.1);
    color: var(--primary);
    font-size: 14px;
  }

  .intro-media {
    position: relative;
  }

  .intro-media img {
    border-radius: 24px;
    border: 1px solid var(--border);
    box-shadow: var(--shadow-card);
  }

  .media-badge {
    position: absolute;
    left: 24px;
    bottom: 24px;
    display: flex;
    align-items: center;
    gap: 10px;
    background: rgba(8, 12, 20, 0.82);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 10px 14px;
    backdrop-filter: blur(10px);
    color: #ffffff;
    font-size: 14px;
    font-weight: 600;
  }

  .badge-icon {
    width: 32px;
    height: 32px;
    border-radius: 8px;
    display: grid;
    place-items: center;
    background: var(--gradient-brand);
    color: #04101f;
  }

  .guide-cards {
    background: var(--bg-deep);
    border-block: 1px solid var(--border-light);
  }

  .guide-card {
    background: var(--bg-card);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-card);
    backdrop-filter: blur(12px);
    overflow: hidden;
    transition: transform .3s ease, border-color .3s ease, box-shadow .3s ease;
  }

  .guide-card:hover {
    transform: translateY(-8px);
    border-color: rgba(0, 229, 255, 0.4);
    box-shadow: 0 20px 48px rgba(0, 229, 255, 0.12);
  }

  .guide-card .card-img-top {
    transition: transform .6s ease;
  }

  .guide-card:hover .card-img-top {
    transform: scale(1.04);
  }

  .guide-card .card-body {
    padding: 26px 24px 28px;
  }

  .badge-soft {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: rgba(124, 77, 255, 0.12);
    border: 1px solid rgba(124, 77, 255, 0.25);
    color: #cfbfff;
    padding: 5px 12px;
    border-radius: 999px;
    font-size: 13px;
  }

  .guide-card .card-title {
    font-weight: 700;
    color: #ffffff;
  }

  .guide-card .card-text {
    color: var(--text-muted);
    font-size: 15px;
  }

  .card-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-top: 12px;
    color: var(--primary);
    font-weight: 600;
    font-size: 14px;
    transition: gap .25s ease, color .25s ease;
  }

  .card-link:hover {
    color: #ffffff;
    gap: 10px;
  }

  .steps-section {
    background: var(--bg-deep);
    border-block: 1px solid var(--border-light);
  }

  .step-list {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
  }

  .step-item {
    position: relative;
    padding: 32px 26px;
    border-radius: var(--radius-lg);
    background: var(--bg-panel);
    border: 1px solid var(--border-light);
    transition: transform .3s, border-color .3s, box-shadow .3s;
  }

  .step-item:hover {
    transform: translateY(-6px);
    border-color: rgba(0, 229, 255, 0.35);
    box-shadow: 0 16px 36px rgba(0, 0, 0, 0.3);
  }

  .step-number {
    width: 52px;
    height: 52px;
    border-radius: 14px;
    background: var(--gradient-brand);
    color: #07111f;
    font-weight: 800;
    display: grid;
    place-items: center;
    font-size: 22px;
    margin-bottom: 20px;
  }

  .step-title {
    font-size: 19px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 10px;
  }

  .step-text {
    color: var(--text-muted);
    font-size: 15px;
  }

  .feature-list {
    background: var(--bg-body);
  }

  .feature-list-row {
    display: grid;
    grid-template-columns: 90px 130px 1fr 44px;
    grid-template-areas: "index cat content btn";
    align-items: center;
    gap: 24px;
    padding: 28px 30px;
    margin-bottom: 16px;
    background: var(--bg-panel);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    transition: border-color .3s, transform .3s, background .3s;
  }

  .feature-list-row:hover {
    border-color: rgba(0, 229, 255, 0.35);
    transform: translateX(6px);
    background: rgba(17, 26, 44, 0.95);
  }

  .feature-index {
    grid-area: index;
    font-size: 28px;
    font-weight: 800;
    color: var(--text-weak);
    font-style: italic;
  }

  .feature-cat {
    grid-area: cat;
  }

  .feature-content {
    grid-area: content;
  }

  .feature-title {
    font-size: 18px;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 6px;
  }

  .feature-summary {
    color: var(--text-muted);
    font-size: 15px;
  }

  .feature-btn {
    grid-area: btn;
    width: 44px;
    height: 44px;
    display: grid;
    place-items: center;
    border-radius: 12px;
    background: rgba(0, 229, 255, 0.08);
    border: 1px solid var(--border);
    color: var(--primary);
    transition: background .3s, color .3s, box-shadow .3s;
  }

  .feature-btn:hover {
    background: var(--primary);
    color: #04101f;
    box-shadow: 0 0 18px rgba(0, 229, 255, 0.4);
  }

  .stats-section {
    position: relative;
    background: linear-gradient(135deg, rgba(13, 19, 34, 0.94), rgba(8, 12, 20, 0.92)), url('/assets/images/backpic/back-3.png') center / cover no-repeat;
    border-block: 1px solid var(--border);
  }

  .stats-panel {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
  }

  .stat-item {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    padding: 30px 20px;
    text-align: center;
    transition: border-color .3s, transform .3s;
  }

  .stat-item:hover {
    border-color: rgba(0, 229, 255, 0.35);
    transform: translateY(-4px);
  }

  .stat-number {
    font-size: 40px;
    font-weight: 800;
    color: #ffffff;
    line-height: 1.2;
  }

  .stat-number small {
    font-size: 16px;
    color: var(--primary);
    margin-left: 2px;
  }

  .stat-label {
    color: var(--text-muted);
    font-size: 14px;
    margin-top: 8px;
  }

  .faq-section {
    background: var(--bg-body);
  }

  .accordion-item {
    background: var(--bg-panel);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md) !important;
    margin-bottom: 16px;
    overflow: hidden;
  }

  .accordion-button {
    background: transparent;
    color: var(--text-main);
    font-weight: 600;
    padding: 22px 26px;
    box-shadow: none !important;
    transition: color .3s, background .3s;
  }

  .accordion-button:not(.collapsed) {
    background: rgba(0, 229, 255, 0.08);
    color: var(--primary);
  }

  .accordion-button:focus {
    box-shadow: 0 0 0 3px rgba(0, 229, 255, 0.2) !important;
  }

  .accordion-button::after {
    filter: invert(73%) sepia(72%) saturate(4295%) hue-rotate(150deg) brightness(101%) contrast(103%);
  }

  .accordion-body {
    color: var(--text-muted);
    padding: 0 26px 24px;
    font-size: 15px;
  }

  .cta-section {
    padding-block: 90px;
    background: var(--bg-deep);
    border-top: 1px solid var(--border);
  }

  .cta-inner {
    position: relative;
    overflow: hidden;
    background: linear-gradient(135deg, rgba(0, 229, 255, 0.14), rgba(124, 77, 255, 0.22));
    border: 1px solid rgba(0, 229, 255, 0.25);
    border-radius: 30px;
    padding: 60px;
    text-align: center;
  }

  .cta-inner::before {
    content: "";
    position: absolute;
    width: 220px;
    height: 220px;
    top: -80px;
    right: -40px;
    background: radial-gradient(circle, rgba(255, 62, 157, 0.28), transparent 70%);
  }

  .cta-inner h2 {
    font-size: clamp(1.8rem, 3vw, 2.6rem);
    font-weight: 800;
    color: #ffffff;
    margin-bottom: 14px;
  }

  .cta-inner p {
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto 28px;
  }

  .cta-actions {
    display: flex;
    gap: 14px;
    justify-content: center;
    flex-wrap: wrap;
  }

  .site-footer {
    padding: 72px 0 32px;
    border-top: 1px solid var(--border);
    background: var(--bg-deep);
  }

  .footer-grid {
    display: grid;
    grid-template-columns: 1.6fr 1fr 1fr;
    gap: 48px;
    margin-bottom: 52px;
  }

  .footer-brand .navbar-brand {
    margin-bottom: 12px;
  }

  .footer-desc {
    color: var(--text-muted);
    font-size: 15px;
    max-width: 420px;
    margin-top: 16px;
  }

  .footer-social {
    display: flex;
    gap: 10px;
    margin-top: 18px;
  }

  .footer-social a {
    width: 38px;
    height: 38px;
    display: grid;
    place-items: center;
    border-radius: 10px;
    border: 1px solid var(--border-light);
    color: var(--text-muted);
    transition: color .3s, border-color .3s, background .3s, transform .3s;
  }

  .footer-social a:hover {
    color: var(--primary);
    border-color: var(--primary);
    background: rgba(0, 229, 255, 0.06);
    transform: translateY(-3px);
  }

  .footer-heading {
    font-size: 17px;
    color: #ffffff;
    margin-bottom: 18px;
    position: relative;
    padding-bottom: 12px;
  }

  .footer-heading::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: 0;
    width: 34px;
    height: 2px;
    background: var(--primary);
    box-shadow: 0 0 8px var(--primary);
  }

  .footer-links li {
    margin-bottom: 8px;
  }

  .footer-links a {
    color: var(--text-muted);
    font-size: 15px;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: color .25s, padding-left .25s;
  }

  .footer-links a:hover {
    color: var(--primary);
    padding-left: 6px;
  }

  .footer-bottom {
    border-top: 1px solid var(--border-light);
    padding-top: 24px;
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 8px;
    color: var(--text-weak);
    font-size: 14px;
  }

  @media (max-width: 1199.98px) {
    .step-list {
      grid-template-columns: repeat(2, 1fr);
    }
  }

  @media (max-width: 991.98px) {
    .navbar-collapse {
      background: var(--bg-deep);
      border: 1px solid var(--border);
      border-radius: 18px;
      padding: 18px;
      margin-top: 14px;
    }

    .navbar-nav {
      gap: 4px;
    }

    .nav-actions {
      margin-left: 0;
      margin-top: 8px;
    }

    .stats-panel {
      grid-template-columns: repeat(2, 1fr);
    }

    .feature-list-row {
      grid-template-columns: 70px 120px 1fr;
      grid-template-areas: "index cat content" "index cat content" "index cat content";
    }

    .feature-btn {
      display: none;
    }
  }

  @media (max-width: 767.98px) {
    .section {
      padding-block: 64px;
    }

    .page-hero {
      padding: 70px 0 58px;
    }

    .step-list {
      grid-template-columns: 1fr;
    }

    .stats-panel {
      grid-template-columns: 1fr 1fr;
    }

    .search-wrap {
      flex-direction: column;
      align-items: stretch;
      border-radius: 22px;
      padding: 16px;
    }

    .search-wrap .btn-neon {
      justify-content: center;
    }

    .footer-grid {
      grid-template-columns: 1fr;
      gap: 36px;
    }

    .cta-inner {
      padding: 40px 24px;
    }

    .cta-actions {
      flex-direction: column;
      align-items: stretch;
    }

    .cta-actions .btn-neon,
    .cta-actions .btn-outline {
      justify-content: center;
    }
  }

  @media (max-width: 575.98px) {
    .hero-title {
      font-size: 2rem;
    }

    .hero-subtitle {
      font-size: 16px;
    }

    .hero-tags {
      gap: 8px;
    }

    .badge-neon {
      padding: 6px 12px;
      font-size: 12px;
    }

    .feature-list-row {
      grid-template-columns: 48px 1fr;
      grid-template-areas: "index cat" "content content";
      gap: 8px 14px;
      padding: 22px;
    }

    .feature-title {
      font-size: 16px;
    }

    .feature-summary {
      font-size: 14px;
    }

    .feature-index {
      font-size: 22px;
    }

    .stats-panel {
      grid-template-columns: 1fr;
    }

    .footer-bottom {
      flex-direction: column;
      text-align: center;
    }
  }