/* ════════════════════════════════════════════════════════════════
   校园帮考研 · 官网样式
   品色：深藏青 #103050 + 金 #f5a623（源自品牌 VI）
   字体：Noto Serif SC（标题·学院气质）/ Noto Sans SC（正文）
   ════════════════════════════════════════════════════════════════ */

/* ─── 设计令牌 ─── */
:root {
  --navy-950: #081827;
  --navy-900: #0c2135;
  --navy-800: #103050;
  --navy-700: #16406b;
  --navy-600: #1d5185;
  --gold-600: #d98b0f;
  --gold-500: #f5a623;
  --gold-400: #ffbe4d;
  --gold-100: #fdf3df;
  --paper: #f8f6f1;
  --paper-deep: #f1ede4;
  --white: #ffffff;
  --ink: #182635;
  --ink-soft: #46586b;
  --ink-faint: #7c8b9c;
  --line: #e7e2d6;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow-sm: 0 2px 10px rgba(12, 33, 53, .07);
  --shadow-md: 0 10px 32px rgba(12, 33, 53, .12);
  --shadow-gold: 0 8px 24px rgba(245, 166, 35, .32);
  --font-display: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", sans-serif;
  --container: 1200px;
  --nav-h: 76px;
  --ease-out: cubic-bezier(.16, 1, .3, 1);
}

/* ─── 基础 ─── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
}

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

a { color: inherit; text-decoration: none; }
ul { list-style: none; }
em { font-style: normal; }

[id] { scroll-margin-top: calc(var(--nav-h) + 12px); }

.container {
  width: min(var(--container), 100% - 48px);
  margin-inline: auto;
}

.skip-link {
  position: absolute;
  top: -60px;
  left: 16px;
  z-index: 100;
  padding: 10px 18px;
  background: var(--gold-500);
  color: var(--navy-900);
  font-weight: 700;
  border-radius: 8px;
  transition: top .2s;
}
.skip-link:focus { top: 12px; }

/* ─── 通用组件 ─── */
.section { padding: 104px 0; }
.section-paper { background: var(--paper); }
.section-dark {
  background:
    radial-gradient(900px 460px at 88% -8%, rgba(245, 166, 35, .09), transparent 62%),
    radial-gradient(760px 420px at -6% 106%, rgba(29, 81, 133, .55), transparent 60%),
    var(--navy-900);
  color: #e8edf3;
}

.sec-head { max-width: 720px; margin-bottom: 64px; }
.kicker {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .22em;
  color: var(--gold-600);
  margin-bottom: 14px;
}
.section-dark .kicker { color: var(--gold-400); }
.sec-head h2 {
  font-family: var(--font-display);
  font-size: clamp(30px, 4vw, 42px);
  font-weight: 900;
  line-height: 1.25;
  color: var(--navy-800);
  margin-bottom: 18px;
}
.section-dark .sec-head h2 { color: var(--white); }
.sec-desc { font-size: 16.5px; color: var(--ink-soft); }
.section-dark .sec-desc { color: rgba(232, 237, 243, .72); }

.sub-title {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 700;
  color: var(--navy-800);
  margin: 72px 0 28px;
  padding-left: 14px;
  border-left: 4px solid var(--gold-500);
}
.sub-title-dark { color: var(--white); }
.sub-title:first-child { margin-top: 0; }

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 15px 34px;
  border-radius: 999px;
  font-size: 16px;
  font-weight: 700;
  line-height: 1.2;
  border: none;
  cursor: pointer;
  transition: transform .25s var(--ease-out), box-shadow .25s, background-color .25s, border-color .25s;
}
.btn:active { transform: translateY(1px); }

.btn-gold {
  background: linear-gradient(135deg, #ffc14d, #ef9414);
  color: var(--navy-900);
  box-shadow: var(--shadow-gold);
}
.btn-gold:hover { transform: translateY(-2px); box-shadow: 0 14px 32px rgba(245, 166, 35, .42); }

.btn-ghost {
  background: rgba(255, 255, 255, .04);
  color: var(--white);
  border: 1px solid rgba(255, 255, 255, .38);
}
.btn-ghost:hover { background: rgba(255, 255, 255, .1); border-color: rgba(255, 255, 255, .6); }

.btn-navy {
  background: var(--navy-800);
  color: var(--white);
  box-shadow: 0 10px 26px rgba(8, 24, 39, .35);
}
.btn-navy:hover { transform: translateY(-2px); background: var(--navy-700); }

.btn-sm { padding: 10px 24px; font-size: 14.5px; }

.gold-rule {
  width: 68px;
  height: 3px;
  border-radius: 2px;
  background: linear-gradient(90deg, #ffc14d, #ef9414);
  margin: 26px 0;
}

/* ─── 导航 ─── */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  background: rgba(10, 28, 45, .82);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid rgba(255, 255, 255, .07);
  transition: background .3s, box-shadow .3s;
}
.nav.scrolled {
  background: rgba(8, 24, 39, .95);
  box-shadow: 0 8px 30px rgba(4, 12, 20, .5);
}
.nav-inner {
  height: var(--nav-h);
  display: flex;
  align-items: center;
  gap: 32px;
}

.brand { display: inline-flex; align-items: center; gap: 12px; flex-shrink: 0; }
.brand-mark {
  width: 42px;
  height: 42px;
  border-radius: 11px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, #ffc14d, #ef9414);
  color: var(--navy-900);
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 900;
  box-shadow: 0 4px 14px rgba(245, 166, 35, .35);
}
.brand-text { display: flex; flex-direction: column; line-height: 1.2; }
.brand-text strong {
  color: var(--white);
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 900;
  letter-spacing: .02em;
}
.brand-text strong em { color: var(--gold-400); }
.brand-domain {
  font-size: 10px;
  letter-spacing: .32em;
  color: rgba(255, 255, 255, .5);
  transform: translateY(1px);
}

.nav-links { display: flex; align-items: center; gap: 6px; margin-left: auto; }
.nav-links a {
  position: relative;
  padding: 10px 15px;
  font-size: 15px;
  font-weight: 500;
  color: rgba(255, 255, 255, .78);
  border-radius: 8px;
  transition: color .25s;
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 15px;
  right: 15px;
  bottom: 4px;
  height: 2px;
  border-radius: 1px;
  background: var(--gold-500);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .3s var(--ease-out);
}
.nav-links a:hover, .nav-links a.active { color: var(--white); }
.nav-links a:hover::after, .nav-links a.active::after { transform: scaleX(1); }

.nav-cta { flex-shrink: 0; }

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  background: rgba(255, 255, 255, .06);
  border: 1px solid rgba(255, 255, 255, .14);
  border-radius: 10px;
  cursor: pointer;
  margin-left: auto;
}
.nav-toggle span {
  display: block;
  height: 2px;
  border-radius: 1px;
  background: var(--white);
  transition: transform .3s, opacity .3s;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.mobile-menu {
  display: none;
  overflow: hidden;
  max-height: 0;
  transition: max-height .4s var(--ease-out);
  background: rgba(8, 24, 39, .98);
  border-bottom: 1px solid rgba(255, 255, 255, .07);
}
.mobile-menu nav {
  display: flex;
  flex-direction: column;
  padding: 12px 24px 24px;
}
.mobile-menu a {
  padding: 13px 4px;
  color: rgba(255, 255, 255, .82);
  font-size: 15.5px;
  font-weight: 500;
  border-bottom: 1px solid rgba(255, 255, 255, .06);
}
.mobile-menu .mobile-cta { margin-top: 16px; border-bottom: none; }

/* ─── 首屏 ─── */
.hero {
  position: relative;
  padding: calc(var(--nav-h) + 88px) 0 0;
  color: var(--white);
  background:
    radial-gradient(1100px 560px at 78% -12%, rgba(245, 166, 35, .13), transparent 62%),
    radial-gradient(860px 480px at -8% 108%, rgba(29, 81, 133, .5), transparent 62%),
    var(--navy-900);
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, .035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, .035) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(720px 480px at 30% 20%, #000 30%, transparent 78%);
  -webkit-mask-image: radial-gradient(720px 480px at 30% 20%, #000 30%, transparent 78%);
  pointer-events: none;
}

.hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  align-items: center;
  gap: 56px;
  padding-bottom: 96px;
}

.hero-badge {
  display: inline-block;
  padding: 8px 18px;
  border-radius: 999px;
  border: 1px solid rgba(245, 166, 35, .45);
  background: rgba(245, 166, 35, .1);
  color: var(--gold-400);
  font-size: 13.5px;
  font-weight: 700;
  letter-spacing: .12em;
  margin-bottom: 30px;
}
.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(42px, 6.2vw, 72px);
  font-weight: 900;
  line-height: 1.18;
  letter-spacing: .01em;
}
.hero h1 .accent {
  background: linear-gradient(100deg, #ffd479, #f09819);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-sub {
  max-width: 540px;
  font-size: 17px;
  line-height: 1.9;
  color: rgba(232, 237, 243, .75);
}
.hero .gold-rule { margin: 28px 0 24px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 16px; margin-top: 38px; }

.hero-art { position: relative; }
.hero-art > svg { width: 100%; height: auto; }
.chip {
  position: absolute;
  padding: 9px 16px;
  border-radius: 999px;
  border: 1px solid rgba(245, 166, 35, .4);
  background: rgba(8, 24, 39, .72);
  backdrop-filter: blur(6px);
  color: var(--gold-400);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .05em;
  white-space: nowrap;
  animation: float-y 6s ease-in-out infinite;
}
.chip-1 { top: 10%; left: -6%; }
.chip-2 { top: 42%; right: -7%; animation-delay: -2s; }
.chip-3 { bottom: 7%; left: 10%; animation-delay: -4s; }

@keyframes float-y {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

/* 数据带 */
.stats-band {
  position: relative;
  border-top: 1px solid rgba(255, 255, 255, .09);
  background: rgba(255, 255, 255, .028);
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  padding: 46px 0;
}
.stat { text-align: center; padding: 14px 10px; }
.stat + .stat { border-left: 1px solid rgba(255, 255, 255, .07); }
.stat:nth-child(5) { border-left: none; }
.stat-num {
  font-family: var(--font-display);
  font-weight: 900;
  color: var(--gold-400);
  line-height: 1.1;
  margin-bottom: 8px;
}
.stat-num .count {
  font-size: clamp(34px, 3.4vw, 44px);
  font-variant-numeric: tabular-nums;
}
.stat-num em { font-size: 19px; margin-left: 3px; color: rgba(255, 190, 77, .85); }
.stat p { font-size: 13.5px; color: rgba(232, 237, 243, .62); letter-spacing: .04em; }

/* ─── 关于我们 ─── */
.about-grid {
  display: grid;
  grid-template-columns: 1.25fr .75fr;
  gap: 40px;
  align-items: start;
}
.about-main {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 44px 46px;
  box-shadow: var(--shadow-sm);
}
.about-main h3 {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 900;
  color: var(--navy-800);
  margin-bottom: 16px;
}
.about-main > p { color: var(--ink-soft); margin-bottom: 24px; }

.about-points { display: grid; gap: 14px; margin-bottom: 32px; }
.about-points li {
  display: grid;
  grid-template-columns: 128px 1fr;
  gap: 14px;
  padding: 14px 18px;
  background: var(--paper);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--gold-500);
}
.about-points b { color: var(--navy-800); font-size: 15px; }
.about-points span { color: var(--ink-soft); font-size: 14.5px; line-height: 1.65; }

.founder-quote {
  position: relative;
  padding: 28px 30px 24px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, rgba(16, 48, 80, .045), rgba(245, 166, 35, .05));
  border: 1px dashed rgba(16, 48, 80, .22);
}
.founder-quote::before {
  content: "“";
  position: absolute;
  top: -6px;
  left: 18px;
  font-family: var(--font-display);
  font-size: 64px;
  line-height: 1;
  color: rgba(245, 166, 35, .5);
}
.founder-quote p {
  font-family: var(--font-display);
  font-size: 16.5px;
  font-weight: 600;
  line-height: 2;
  color: var(--navy-800);
}
.founder-quote footer {
  margin-top: 14px;
  text-align: right;
  font-size: 14px;
  font-weight: 700;
  color: var(--gold-600);
  letter-spacing: .06em;
}

.culture-card {
  background: linear-gradient(160deg, var(--navy-800), var(--navy-950) 70%);
  border-radius: var(--radius);
  padding: 36px 34px;
  color: #e8edf3;
  box-shadow: var(--shadow-md);
  position: sticky;
  top: calc(var(--nav-h) + 24px);
}
.culture-card h3 {
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 900;
  color: var(--white);
  padding-bottom: 18px;
  margin-bottom: 8px;
  border-bottom: 1px solid rgba(255, 255, 255, .12);
}
.culture-list { display: grid; gap: 4px; }
.culture-list > div {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 14px;
  align-items: baseline;
  padding: 13px 4px;
  border-bottom: 1px solid rgba(255, 255, 255, .06);
}
.culture-list > div:last-child { border-bottom: none; }
.culture-list dt {
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: .18em;
  color: var(--gold-400);
}
.culture-list dd { font-size: 15px; line-height: 1.6; }
.culture-list .is-motto dd {
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--gold-400);
}

.party-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 40px;
}
.party-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 34px 32px;
  box-shadow: var(--shadow-sm);
  transition: transform .3s var(--ease-out), box-shadow .3s;
}
.party-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-md); }
.party-for {
  display: inline-block;
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: .16em;
  color: var(--gold-600);
  margin-bottom: 12px;
}
.party-card h3 {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 900;
  color: var(--navy-800);
  margin-bottom: 12px;
}
.party-desc { font-size: 14.5px; color: var(--ink-soft); line-height: 1.85; }

/* ─── 核心优势 ─── */
.adv-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 20px;
}
.adv-card {
  background: rgba(255, 255, 255, .045);
  border: 1px solid rgba(255, 255, 255, .09);
  border-radius: var(--radius);
  padding: 30px 24px;
  transition: transform .3s var(--ease-out), background-color .3s, border-color .3s;
}
.adv-card:hover {
  transform: translateY(-6px);
  background: rgba(245, 166, 35, .07);
  border-color: rgba(245, 166, 35, .35);
}
.adv-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  margin-bottom: 20px;
  background: rgba(245, 166, 35, .12);
  border: 1px solid rgba(245, 166, 35, .3);
  color: var(--gold-400);
}
.adv-icon svg { width: 26px; height: 26px; }
.adv-card h3 {
  font-size: 17px;
  font-weight: 700;
  color: var(--white);
  margin-bottom: 10px;
}
.adv-card p { font-size: 13.5px; line-height: 1.75; color: rgba(232, 237, 243, .66); }

.six-wrap { margin-top: 84px; }
.six-head { text-align: center; margin-bottom: 48px; }
.six-head h3 {
  font-family: var(--font-display);
  font-size: clamp(24px, 3vw, 32px);
  font-weight: 900;
  color: var(--white);
  margin-bottom: 12px;
}
.six-head p { color: rgba(232, 237, 243, .65); font-size: 15px; }

.six-grid {
  position: relative;
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 16px;
}
.six-grid::before {
  content: "";
  position: absolute;
  top: 36px;
  left: 8%;
  right: 8%;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(245, 166, 35, .4) 18%, rgba(245, 166, 35, .4) 82%, transparent);
}
.six-item {
  position: relative;
  text-align: center;
  padding: 0 8px;
}
.seal {
  width: 72px;
  height: 72px;
  margin: 0 auto 18px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: rgba(245, 166, 35, .08);
  border: 1.5px solid var(--gold-500);
  color: var(--gold-400);
  font-family: var(--font-display);
  font-size: 32px;
  font-weight: 900;
  box-shadow: 0 0 0 6px rgba(245, 166, 35, .05), inset 0 0 18px rgba(245, 166, 35, .12);
}
.six-item h4 { font-size: 15.5px; font-weight: 700; color: var(--white); margin-bottom: 8px; }
.six-item p { font-size: 12.5px; line-height: 1.7; color: rgba(232, 237, 243, .6); }

/* ─── 产品服务 ─── */
.course-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.course-card {
  position: relative;
  display: flex;
  flex-direction: column;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 36px 36px 30px;
  box-shadow: var(--shadow-sm);
  transition: transform .3s var(--ease-out), box-shadow .3s;
}
.course-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-md); }
.course-tag {
  align-self: flex-start;
  padding: 5px 14px;
  border-radius: 999px;
  background: var(--paper-deep);
  color: var(--ink-soft);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .1em;
  margin-bottom: 18px;
}
.tag-hot { background: rgba(220, 53, 69, .09); color: #c22f42; }
.tag-gold { background: linear-gradient(135deg, #ffc14d, #ef9414); color: var(--navy-900); }
.course-card h4 {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 900;
  color: var(--navy-800);
}
.course-series { font-size: 13px; color: var(--ink-faint); letter-spacing: .04em; margin: 6px 0 4px; }
.course-price {
  font-family: var(--font-display);
  font-size: 26px;
  font-weight: 900;
  color: var(--gold-600);
  margin: 6px 0 10px;
}
.course-price span { font-size: 14px; font-weight: 700; color: var(--ink-faint); margin-left: 2px; }
.course-desc { font-size: 14.5px; color: var(--ink-soft); line-height: 1.85; margin-bottom: 18px; flex: 1; }
.course-fit {
  padding-top: 16px;
  border-top: 1px dashed var(--line);
  font-size: 13.5px;
  color: var(--ink-soft);
  line-height: 1.7;
}
.course-fit b {
  display: inline-block;
  margin-right: 8px;
  padding: 2px 10px;
  border-radius: 6px;
  background: var(--paper-deep);
  color: var(--navy-700);
  font-size: 12px;
}

.course-featured {
  grid-column: 1 / -1;
  flex-direction: row;
  align-items: center;
  gap: 40px;
  background:
    radial-gradient(520px 240px at 92% 50%, rgba(245, 166, 35, .16), transparent 68%),
    linear-gradient(135deg, var(--navy-800), var(--navy-950));
  border: 1px solid rgba(245, 166, 35, .4);
  color: #e8edf3;
}
.course-featured:hover { transform: translateY(-5px); box-shadow: 0 18px 44px rgba(8, 24, 39, .4); }
.featured-copy { flex: 1; }
.featured-copy .course-tag { background: rgba(245, 166, 35, .16); color: var(--gold-400); }
.featured-copy h4 { color: var(--white); font-size: 24px; }
.featured-copy .course-desc { color: rgba(232, 237, 243, .75); margin-bottom: 14px; }
.featured-copy .course-fit {
  border-top: 1px dashed rgba(255, 255, 255, .18);
  color: rgba(232, 237, 243, .72);
}
.featured-copy .course-fit b { background: rgba(255, 255, 255, .08); color: var(--gold-400); }
.featured-badge { position: relative; width: 148px; height: 148px; flex-shrink: 0; }
.featured-badge-ring {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 1.5px dashed rgba(245, 166, 35, .55);
  animation: spin 26s linear infinite;
}
.featured-badge-core {
  position: absolute;
  inset: 16px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  text-align: center;
  background: linear-gradient(135deg, #ffc14d, #ef9414);
  color: var(--navy-900);
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 900;
  line-height: 1.3;
  box-shadow: var(--shadow-gold);
}
@keyframes spin { to { transform: rotate(360deg); } }

/* 百校文库 */
.library-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.lib-card {
  position: relative;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 36px 32px;
  box-shadow: var(--shadow-sm);
  transition: transform .3s var(--ease-out), box-shadow .3s;
}
.lib-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-md); }
.lib-no {
  font-family: var(--font-display);
  font-size: 42px;
  font-weight: 900;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1.2px rgba(245, 166, 35, .65);
  margin-bottom: 18px;
}
.lib-card h4 {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 900;
  color: var(--navy-800);
  margin-bottom: 10px;
}
.lib-card p { font-size: 14.5px; color: var(--ink-soft); line-height: 1.85; }

.lib-strip {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 16px 32px;
  margin-top: 24px;
  padding: 22px 32px;
  border-radius: var(--radius);
  background: var(--navy-800);
  color: rgba(232, 237, 243, .85);
  font-size: 14.5px;
  text-align: center;
}
.lib-strip b { color: var(--gold-400); margin-right: 8px; }
.strip-divider {
  width: 1px;
  height: 22px;
  background: rgba(255, 255, 255, .2);
}

/* 平台工具 */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.tool-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 26px;
  box-shadow: var(--shadow-sm);
  transition: transform .3s var(--ease-out), box-shadow .3s, border-color .3s;
}
.tool-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-md); border-color: rgba(245, 166, 35, .5); }
.tool-icon {
  width: 50px;
  height: 50px;
  border-radius: 13px;
  display: grid;
  place-items: center;
  margin-bottom: 18px;
  background: var(--gold-100);
  border: 1px solid rgba(245, 166, 35, .35);
  color: var(--gold-600);
}
.tool-icon svg { width: 25px; height: 25px; }
.tool-card h4 { font-family: var(--font-display); font-size: 18.5px; font-weight: 900; color: var(--navy-800); }
.tool-site { font-size: 12.5px; font-weight: 700; letter-spacing: .05em; color: var(--gold-600); margin: 4px 0 10px; }
.tool-card > p:last-child { font-size: 13.5px; color: var(--ink-soft); line-height: 1.75; }

/* ─── 发展历程 ─── */
.timeline {
  position: relative;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 28px;
}
.timeline::before {
  content: "";
  position: absolute;
  top: 9px;
  left: 2%;
  right: 2%;
  height: 2px;
  background: linear-gradient(90deg, rgba(245, 166, 35, .25), rgba(245, 166, 35, .7) 50%, rgba(245, 166, 35, .25));
  border-radius: 1px;
}
.tl-item { position: relative; padding-top: 42px; }
.tl-node {
  position: absolute;
  top: 0;
  left: 0;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--white);
  border: 4px solid var(--gold-500);
  box-shadow: 0 0 0 5px rgba(245, 166, 35, .16);
}
.tl-year {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--gold-600);
  margin-bottom: 8px;
}
.tl-item h3 {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 900;
  color: var(--navy-800);
  margin-bottom: 10px;
}
.tl-desc { font-size: 14px; color: var(--ink-soft); line-height: 1.8; }

.coverage {
  margin-top: 72px;
  padding: 36px 40px;
  border-radius: var(--radius);
  background: var(--paper);
  border: 1px solid var(--line);
  text-align: center;
}
.coverage-title {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 900;
  color: var(--navy-800);
  margin-bottom: 20px;
}
.coverage-list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}
.coverage-list li {
  padding: 9px 22px;
  border-radius: 999px;
  background: var(--white);
  border: 1px solid rgba(16, 48, 80, .16);
  color: var(--navy-700);
  font-size: 14.5px;
  font-weight: 700;
  transition: transform .25s var(--ease-out), border-color .25s, color .25s;
}
.coverage-list li:hover {
  transform: translateY(-3px);
  border-color: var(--gold-500);
  color: var(--gold-600);
}
.coverage-note { margin-top: 20px; font-size: 13.5px; color: var(--ink-faint); letter-spacing: .06em; }

/* ─── 合作生态 ─── */
.value-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.value-card {
  background: rgba(255, 255, 255, .045);
  border: 1px solid rgba(255, 255, 255, .09);
  border-radius: var(--radius);
  padding: 34px 32px;
  transition: transform .3s var(--ease-out), background-color .3s, border-color .3s;
}
.value-card:hover {
  transform: translateY(-5px);
  background: rgba(245, 166, 35, .06);
  border-color: rgba(245, 166, 35, .32);
}
.value-tag {
  display: inline-block;
  padding: 5px 14px;
  border-radius: 999px;
  background: rgba(245, 166, 35, .14);
  border: 1px solid rgba(245, 166, 35, .35);
  color: var(--gold-400);
  font-size: 12.5px;
  font-weight: 700;
  letter-spacing: .1em;
  margin-bottom: 16px;
}
.value-card h3 {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 900;
  color: var(--white);
  margin-bottom: 18px;
}
.value-card ul { display: grid; gap: 11px; }
.value-card li {
  position: relative;
  padding-left: 22px;
  font-size: 13.5px;
  line-height: 1.7;
  color: rgba(232, 237, 243, .68);
}
.value-card li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 9px;
  width: 7px;
  height: 7px;
  border-radius: 2px;
  transform: rotate(45deg);
  background: var(--gold-500);
}

.invite-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}
.invite-card {
  background: rgba(255, 255, 255, .045);
  border: 1px solid rgba(255, 255, 255, .09);
  border-radius: var(--radius);
  padding: 30px 26px;
  transition: transform .3s var(--ease-out), background-color .3s, border-color .3s;
}
.invite-card:hover {
  transform: translateY(-5px);
  background: rgba(245, 166, 35, .06);
  border-color: rgba(245, 166, 35, .32);
}
.invite-no {
  font-family: var(--font-display);
  font-size: 34px;
  font-weight: 900;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px rgba(245, 166, 35, .7);
  margin-bottom: 16px;
}
.invite-card h4 { font-size: 16.5px; font-weight: 700; color: var(--white); margin-bottom: 10px; }
.invite-card p { font-size: 13px; line-height: 1.75; color: rgba(232, 237, 243, .62); }

/* ─── 联系我们 ─── */
.contact-grid {
  display: grid;
  grid-template-columns: .9fr 1.1fr;
  gap: 32px;
  align-items: start;
}
.contact-info { display: grid; gap: 20px; }
.info-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 30px;
  box-shadow: var(--shadow-sm);
}
.info-card h3 {
  font-family: var(--font-display);
  font-size: 17.5px;
  font-weight: 900;
  color: var(--navy-800);
  margin-bottom: 10px;
}
.info-link a {
  font-size: 17px;
  font-weight: 700;
  color: var(--navy-600);
  border-bottom: 2px solid rgba(245, 166, 35, .5);
  transition: color .25s, border-color .25s;
}
.info-link a:hover { color: var(--gold-600); border-color: var(--gold-500); }
.media-row { font-size: 15.5px; font-weight: 700; color: var(--navy-800); }
.info-sub { margin-top: 8px; font-size: 13.5px; color: var(--ink-faint); line-height: 1.7; }

.info-cta {
  background:
    radial-gradient(300px 160px at 90% 0%, rgba(245, 166, 35, .14), transparent 70%),
    linear-gradient(135deg, var(--navy-800), var(--navy-950));
  border: 1px solid rgba(245, 166, 35, .35);
  color: #e8edf3;
}
.info-cta h3 { color: var(--white); }
.info-cta > p { font-size: 14px; color: rgba(232, 237, 243, .72); margin-bottom: 22px; }

.office-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}
.office-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 22px 24px;
  box-shadow: var(--shadow-sm);
  transition: transform .3s var(--ease-out), box-shadow .3s, border-color .3s;
}
.office-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: rgba(245, 166, 35, .5); }
.office-city {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 900;
  color: var(--navy-800);
  margin-bottom: 6px;
}
.office-city span {
  font-family: var(--font-body);
  font-size: 11.5px;
  font-weight: 700;
  letter-spacing: .06em;
  color: var(--gold-600);
  background: var(--gold-100);
  padding: 3px 10px;
  border-radius: 999px;
  margin-left: 8px;
  vertical-align: 2px;
}
.office-addr { font-size: 13px; color: var(--ink-soft); line-height: 1.7; }
.office-more {
  grid-column: 1 / -1;
  text-align: center;
  font-size: 13.5px;
  color: var(--ink-faint);
  padding: 6px 0 2px;
  letter-spacing: .04em;
}

/* ─── 结尾 CTA ─── */
.cta-banner {
  padding: 96px 0;
  text-align: center;
  background:
    radial-gradient(680px 300px at 50% 120%, rgba(8, 24, 39, .22), transparent 70%),
    linear-gradient(135deg, #ffc14d, #ef9414);
}
.cta-banner h2 {
  font-family: var(--font-display);
  font-size: clamp(28px, 4vw, 42px);
  font-weight: 900;
  color: var(--navy-900);
  margin-bottom: 14px;
}
.cta-banner > .container > p {
  font-size: 16px;
  font-weight: 500;
  color: rgba(8, 24, 39, .78);
  margin-bottom: 36px;
}

/* ─── 页脚 ─── */
.footer {
  background:
    radial-gradient(800px 400px at 85% 0%, rgba(29, 81, 133, .35), transparent 65%),
    var(--navy-950);
  color: rgba(232, 237, 243, .68);
  padding: 72px 0 0;
}
.footer-top {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 48px;
  padding-bottom: 56px;
  border-bottom: 1px solid rgba(255, 255, 255, .08);
}
.footer-motto {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  color: var(--gold-400);
  margin-top: 26px;
  letter-spacing: .08em;
}
.footer-note { font-size: 13.5px; color: rgba(232, 237, 243, .5); margin-top: 8px; }

.footer-nav { display: flex; gap: clamp(40px, 8vw, 110px); }
.footer-nav h4 {
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .14em;
  color: rgba(255, 255, 255, .88);
  margin-bottom: 18px;
}
.footer-nav a {
  display: block;
  padding: 6px 0;
  font-size: 14px;
  color: rgba(232, 237, 243, .58);
  transition: color .25s;
}
.footer-nav a:hover { color: var(--gold-400); }

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 10px 24px;
  padding: 26px 0;
  font-size: 13px;
  color: rgba(232, 237, 243, .42);
}
.footer-slogan { font-family: var(--font-display); font-weight: 700; color: rgba(245, 166, 35, .55); letter-spacing: .1em; }

/* ─── 滚动显现动画（fail-open：无 JS 时内容直接可见）─── */
.js .reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity .8s var(--ease-out), transform .8s var(--ease-out);
}
.js .reveal.is-visible { opacity: 1; transform: translateY(0); }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .js .reveal { opacity: 1; transform: none; transition: none; }
  .chip, .featured-badge-ring { animation: none; }
  .btn, .adv-card, .party-card, .course-card, .lib-card, .tool-card,
  .office-card, .invite-card, .value-card, .coverage-list li { transition: none; }
}

/* ════════════════ 响应式 ════════════════ */
@media (max-width: 1180px) {
  .adv-grid { grid-template-columns: repeat(3, 1fr); }
  .six-grid { grid-template-columns: repeat(3, 1fr); row-gap: 40px; }
  .six-grid::before { display: none; }
  .tool-grid { grid-template-columns: repeat(2, 1fr); }
  .nav-cards { grid-template-columns: repeat(2, 1fr); }
  .invite-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 1024px) {
  .section { padding: 84px 0; }
  .nav-links, .nav-cta { display: none; }
  .nav-toggle { display: flex; }
  .mobile-menu { display: block; }

  .hero-grid { grid-template-columns: 1fr; gap: 40px; padding-bottom: 72px; }
  .hero-art { max-width: 460px; margin: 0 auto; }
  .stats-grid { grid-template-columns: repeat(4, 1fr); }

  .about-grid { grid-template-columns: 1fr; }
  .culture-card { position: static; }

  .timeline { grid-template-columns: repeat(2, 1fr); gap: 36px 28px; }
  .timeline::before { display: none; }

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

@media (max-width: 720px) {
  .section { padding: 64px 0; }
  .sec-head { margin-bottom: 44px; }
  .sub-title { margin: 52px 0 22px; }

  .hero { padding-top: calc(var(--nav-h) + 48px); }
  .hero h1 { font-size: clamp(36px, 11vw, 48px); }
  .hero-actions .btn { width: 100%; }
  .hero-art { max-width: 360px; }
  .chip-1 { left: 0; }
  .chip-2 { right: 0; }

  .stats-grid { grid-template-columns: repeat(2, 1fr); padding: 30px 0; gap: 20px 0; }
  .stat { padding: 6px 4px; }
  .stat:nth-child(5) { border-left: 1px solid rgba(255, 255, 255, .07); }
  .stat:nth-child(odd) { border-left: none; }

  .about-main { padding: 30px 24px; }
  .about-points li { grid-template-columns: 1fr; gap: 4px; }

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

  .course-grid { grid-template-columns: 1fr; }
  .course-featured { flex-direction: column; align-items: flex-start; gap: 24px; }
  .featured-badge { width: 120px; height: 120px; }
  .featured-badge-core { font-size: 18px; inset: 13px; }

  .library-grid { grid-template-columns: 1fr; }
  .lib-strip { flex-direction: column; gap: 10px; }
  .strip-divider { display: none; }
  .tool-grid { grid-template-columns: 1fr; }

  .timeline { grid-template-columns: 1fr; }
  .tl-item { padding-top: 0; padding-left: 34px; }
  .tl-item::before {
    content: "";
    position: absolute;
    left: 9px;
    top: 22px;
    bottom: -34px;
    width: 2px;
    background: linear-gradient(rgba(245, 166, 35, .5), rgba(245, 166, 35, .1));
  }
  .tl-item:last-child::before { display: none; }
  .tl-node { top: 14px; }

  .value-grid { grid-template-columns: 1fr; }
  .invite-grid { grid-template-columns: 1fr; }
  .office-grid { grid-template-columns: 1fr; }

  .footer-nav { gap: 32px; flex-wrap: wrap; }
  .cta-banner { padding: 72px 0; }
}

@media (max-width: 420px) {
  .container { width: calc(100% - 40px); }
  .adv-grid { grid-template-columns: 1fr; }
  .six-grid { grid-template-columns: 1fr 1fr; }
  .brand-text strong { font-size: 18px; }
}

/* ════════════════ 子页页首横幅 ════════════════ */
.page-hero {
  position: relative;
  padding: calc(var(--nav-h) + 76px) 0 72px;
  color: var(--white);
  background:
    radial-gradient(1000px 480px at 82% -20%, rgba(245, 166, 35, .12), transparent 62%),
    radial-gradient(760px 420px at -8% 130%, rgba(29, 81, 133, .5), transparent 62%),
    var(--navy-900);
  overflow: hidden;
}
.page-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, .035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, .035) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(680px 420px at 30% 30%, #000 30%, transparent 78%);
  -webkit-mask-image: radial-gradient(680px 420px at 30% 30%, #000 30%, transparent 78%);
  pointer-events: none;
}
.page-hero > .container { position: relative; }
.page-hero .kicker { color: var(--gold-400); }
.page-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(32px, 4.6vw, 48px);
  font-weight: 900;
  line-height: 1.25;
}
.page-hero .gold-rule { margin: 24px 0; }
.page-hero .page-desc {
  max-width: 680px;
  font-size: 16.5px;
  line-height: 1.9;
  color: rgba(232, 237, 243, .75);
}
.page-hero + .section { padding-top: 88px; }

/* ════════════════ 首页板块导览卡片 ════════════════ */
.nav-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}
.nav-card {
  display: flex;
  flex-direction: column;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 32px 26px 28px;
  box-shadow: var(--shadow-sm);
  transition: transform .3s var(--ease-out), box-shadow .3s, border-color .3s;
}
.nav-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: rgba(245, 166, 35, .55);
}
.nc-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 22px;
}
.nc-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  background: var(--gold-100);
  border: 1px solid rgba(245, 166, 35, .35);
  color: var(--gold-600);
}
.nc-icon svg { width: 26px; height: 26px; }
.nc-no {
  font-family: var(--font-display);
  font-size: 42px;
  font-weight: 900;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1.2px rgba(245, 166, 35, .55);
}
.nav-card h3 {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 900;
  color: var(--navy-800);
  margin-bottom: 10px;
}
.nav-card p {
  flex: 1;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ink-soft);
}
.nc-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 24px;
  font-size: 14.5px;
  font-weight: 700;
  color: var(--gold-600);
  transition: gap .3s var(--ease-out), color .25s;
}
.nav-card:hover .nc-link { gap: 14px; color: var(--gold-500); }

/* 百校文库副标题下的引导句 */
.library-intro {
  margin: -12px 0 26px;
  padding-left: 14px;
  font-size: 15px;
  color: var(--ink-soft);
}

/* ─── 导览卡片响应式 ─── */
@media (max-width: 1024px) {
  .nav-cards { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 720px) {
  .page-hero { padding: calc(var(--nav-h) + 52px) 0 56px; }
  .page-hero + .section { padding-top: 60px; }
  .nav-cards { grid-template-columns: 1fr; }
}
@media (max-width: 420px) {
  .nav-cards { grid-template-columns: 1fr; }
}