:root {
  --pku-red: #C8102E;
  --pku-red-dark: #9E0C24;
  --pku-gold: #B8995A;
  --ink: #1A1A1A;
  --ink-soft: #4A4A4A;
  --muted: #8A8A8A;
  --bg: #FFFFFF;
  --bg-alt: #F6F4EF;
  --bg-dark: #1C1A18;
  --line: #E7E2D8;
  --radius: 14px;
  --shadow: 0 18px 40px rgba(26, 22, 18, 0.10);
  --shadow-sm: 0 8px 22px rgba(26, 22, 18, 0.08);
  --maxw: 1180px;
  --serif: "Noto Serif SC", "Songti SC", "STSong", "SimSun", Georgia, serif;
  --sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
.container { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- 顶部条 ---------- */
.topbar {
  background: var(--bg-dark);
  color: #E9E4DA;
  font-size: 13px;
}
.topbar-inner {
  display: flex; justify-content: space-between; align-items: center;
  height: 40px;
}
.topbar-right { display: flex; gap: 12px; align-items: center; color: #C9C2B5; }
.topbar-sep { color: #555; }
.topbar-item { white-space: nowrap; }

/* ---------- 导航 ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,0.92);
  backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--line);
  transition: box-shadow .3s ease;
}
.nav.scrolled { box-shadow: var(--shadow-sm); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark {
  display: inline-flex; align-items: center; justify-content: center;
  width: 44px; height: 44px; border-radius: 10px;
  background: var(--pku-red); color: #fff; font-family: var(--serif);
  font-weight: 700; font-size: 18px; letter-spacing: 1px;
}
.brand-text { display: flex; flex-direction: column; line-height: 1.2; }
.brand-text strong { font-size: 17px; }
.brand-text em { font-style: normal; font-size: 11px; color: var(--muted); letter-spacing: .5px; }
.nav-links { display: flex; gap: 22px; margin-left: auto; margin-right: 20px; }
.nav-links a { font-size: 15px; color: var(--ink-soft); position: relative; padding: 6px 0; transition: color .2s; }
.nav-links a::after {
  content: ""; position: absolute; left: 0; bottom: 0; height: 2px; width: 0;
  background: var(--pku-red); transition: width .25s ease;
}
.nav-links a:hover { color: var(--pku-red); }
.nav-links a:hover::after { width: 100%; }

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 12px 24px; border-radius: 999px; font-size: 15px; font-weight: 600;
  cursor: pointer; border: 1px solid transparent; transition: all .2s ease;
  font-family: var(--sans);
}
.btn-primary { background: var(--pku-red); color: #fff; }
.btn-primary:hover { background: var(--pku-red-dark); transform: translateY(-1px); box-shadow: 0 10px 24px rgba(200,16,46,.28); }
.btn-ghost { background: transparent; color: #fff; border-color: rgba(255,255,255,.6); }
.btn-ghost:hover { background: rgba(255,255,255,.12); border-color: #fff; }
.btn-block { width: 100%; }
.nav-cta { padding: 10px 20px; }

.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 8px; }
.nav-toggle span { width: 24px; height: 2px; background: var(--ink); transition: .3s; }

/* ---------- 首屏 ---------- */
.hero { position: relative; min-height: 88vh; display: flex; align-items: center; overflow: hidden; }
.hero-bg {
  position: absolute; inset: 0;
  background:
    radial-gradient(120% 90% at 80% 10%, rgba(200,16,46,.42), transparent 55%),
    radial-gradient(100% 80% at 10% 90%, rgba(184,153,90,.30), transparent 50%),
    linear-gradient(135deg, #2a1418 0%, #4a1d24 45%, #1c1a18 100%);
}
.hero-bg::after {
  content: ""; position: absolute; inset: 0;
  background-image: linear-gradient(rgba(255,255,255,.04) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255,255,255,.04) 1px, transparent 1px);
  background-size: 44px 44px; opacity: .5;
}
.hero-inner { position: relative; z-index: 2; padding: 80px 24px; }
.hero-content { max-width: 720px; color: #fff; }
.eyebrow {
  display: inline-block; font-size: 13px; letter-spacing: 3px; text-transform: uppercase;
  color: var(--pku-gold); font-weight: 600; margin-bottom: 18px;
}
.eyebrow.light { color: #E5C98A; }
.hero h1 {
  font-family: var(--serif); font-size: clamp(40px, 7vw, 76px); line-height: 1.1;
  font-weight: 700; letter-spacing: 2px;
}
.hero h1 .accent { color: var(--pku-gold); }
.hero-sub { margin: 24px 0 34px; font-size: clamp(16px, 2vw, 19px); color: rgba(255,255,255,.86); max-width: 620px; }
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-stats { display: flex; gap: 44px; margin-top: 54px; flex-wrap: wrap; }
.stat { display: flex; flex-direction: column; }
.stat strong { font-family: var(--serif); font-size: 34px; font-weight: 700; color: #fff; }
.stat span { font-size: 14px; color: rgba(255,255,255,.7); margin-top: 4px; }
.hero-scroll {
  position: absolute; bottom: 26px; left: 50%; transform: translateX(-50%);
  width: 26px; height: 42px; border: 2px solid rgba(255,255,255,.5); border-radius: 14px; z-index: 2;
}
.hero-scroll span {
  position: absolute; top: 8px; left: 50%; transform: translateX(-50%);
  width: 4px; height: 8px; background: #fff; border-radius: 2px; animation: scrolldot 1.8s infinite;
}
@keyframes scrolldot { 0%{opacity:0; top:8px} 40%{opacity:1} 80%{opacity:0; top:24px} 100%{opacity:0} }

/* ---------- 通用 section ---------- */
.section { padding: 96px 0; }
.section-alt { background: var(--bg-alt); }
.section-dark { background: var(--bg-dark); color: #fff; }
.section-head { text-align: center; max-width: 720px; margin: 0 auto 56px; }
.section-head h2 { font-family: var(--serif); font-size: clamp(28px, 4vw, 42px); font-weight: 700; margin: 6px 0 14px; }
.section-head p { color: var(--ink-soft); font-size: 17px; }
.section-dark .section-head p { color: rgba(255,255,255,.75); }

.grid { display: grid; gap: 24px; }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* ---------- 课程特色卡片 ---------- */
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 32px 28px; transition: transform .25s ease, box-shadow .25s ease;
}
.card:hover { transform: translateY(-6px); box-shadow: var(--shadow); }
.card-icon {
  width: 54px; height: 54px; border-radius: 12px; display: flex; align-items: center; justify-content: center;
  font-size: 26px; background: rgba(200,16,46,.08); margin-bottom: 18px;
}
.card h3 { font-size: 19px; margin-bottom: 10px; font-family: var(--serif); }
.card p { color: var(--ink-soft); font-size: 15px; }

/* ---------- 课程模块 ---------- */
.module {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 30px 28px; position: relative; overflow: hidden; transition: transform .25s ease, box-shadow .25s ease;
}
.module::before {
  content: ""; position: absolute; left: 0; top: 0; width: 4px; height: 0; background: var(--pku-red); transition: height .3s ease;
}
.module:hover { transform: translateY(-5px); box-shadow: var(--shadow); }
.module:hover::before { height: 100%; }
.module-no { font-family: var(--serif); font-size: 40px; font-weight: 700; color: var(--line); }
.module h3 { font-family: var(--serif); font-size: 20px; margin: 4px 0 12px; }
.module p { color: var(--ink-soft); font-size: 14.5px; margin-bottom: 14px; }
.module ul { list-style: none; }
.module ul li { font-size: 14px; color: var(--ink-soft); padding: 6px 0 6px 20px; position: relative; border-top: 1px dashed var(--line); }
.module ul li::before { content: "›"; position: absolute; left: 4px; color: var(--pku-red); font-weight: 700; }

/* ---------- 师资 ---------- */
.teacher { text-align: center; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 34px 24px; transition: transform .25s ease, box-shadow .25s ease; }
.teacher:hover { transform: translateY(-6px); box-shadow: var(--shadow); }
.avatar {
  width: 84px; height: 84px; border-radius: 50%; margin: 0 auto 16px;
  display: flex; align-items: center; justify-content: center; color: #fff;
  font-family: var(--serif); font-size: 32px; font-weight: 700; box-shadow: var(--shadow-sm);
}
.avatar-a { background: linear-gradient(135deg, #C8102E, #9E0C24); }
.avatar-b { background: linear-gradient(135deg, #B8995A, #8C7440); }
.avatar-c { background: linear-gradient(135deg, #2E5A88, #1C3A5A); }
.avatar-d { background: linear-gradient(135deg, #4A7C59, #2F5238); }
.avatar-e { background: linear-gradient(135deg, #6B4E9E, #432E63); }
.avatar-f { background: linear-gradient(135deg, #1F8A8A, #135656); }
.avatar img { width: 100%; height: 100%; object-fit: cover; border-radius: 50%; }
.teacher h3 { font-family: var(--serif); font-size: 20px; }
.teacher-title { display: block; color: var(--pku-red); font-size: 13.5px; font-weight: 600; margin: 4px 0 12px; }
.teacher p { color: var(--ink-soft); font-size: 14px; }

/* ---------- 课程中心卡片 ---------- */
.course {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px 24px 22px; display: flex; flex-direction: column; gap: 12px;
  transition: transform .25s ease, box-shadow .25s ease; border-top: 3px solid var(--pku-red);
}
.course:hover { transform: translateY(-5px); box-shadow: var(--shadow); }
.course-tag {
  align-self: flex-start; font-size: 12px; font-weight: 600; padding: 4px 12px; border-radius: 999px;
  letter-spacing: .5px;
}
.tag-strategy { background: rgba(200,16,46,.10); color: var(--pku-red); }
.tag-mgmt { background: rgba(46,90,136,.12); color: #2E5A88; }
.tag-fin { background: rgba(184,153,90,.18); color: #8C7440; }
.tag-guo { background: rgba(74,124,89,.14); color: #2F5238; }
.tag-mkt { background: rgba(120,60,150,.12); color: #6B4E9E; }
.tag-health { background: rgba(31,138,138,.14); color: #135656; }
.course h3 { font-family: var(--serif); font-size: 18px; line-height: 1.4; }
.course-meta { display: flex; justify-content: space-between; gap: 10px; margin-top: auto; padding-top: 8px; border-top: 1px dashed var(--line); font-size: 13.5px; color: var(--ink-soft); }
.course-meta span:first-child { color: var(--pku-red); font-weight: 600; }
.course[data-course] { cursor: pointer; }
.course[data-course]::after {
  content: "查看课程详情 →"; margin-top: 2px; font-size: 13px; font-weight: 600;
  color: var(--pku-red); opacity: .85; transition: opacity .2s;
}
.course[data-course]:hover::after { opacity: 1; }

/* ---------- 课程详情弹窗 ---------- */
.modal { position: fixed; inset: 0; z-index: 100; display: flex; align-items: center; justify-content: center; padding: 20px; }
.modal[hidden] { display: none; }
.modal-mask { position: absolute; inset: 0; background: rgba(22, 17, 14, .58); backdrop-filter: blur(3px); }
.modal-panel {
  position: relative; background: #fff; border-radius: 18px; width: 100%; max-width: 620px;
  max-height: 86vh; overflow: auto; padding: 32px 30px 28px; box-shadow: var(--shadow);
  animation: fadeUp .3s ease;
}
.modal-close {
  position: absolute; top: 12px; right: 14px; width: 36px; height: 36px; border-radius: 50%;
  border: 1px solid var(--line); background: #fff; color: var(--ink-soft); font-size: 20px;
  cursor: pointer; line-height: 1; transition: all .2s;
}
.modal-close:hover { color: var(--pku-red); border-color: var(--pku-red); }
.modal-panel h3 { font-family: var(--serif); font-size: 22px; line-height: 1.4; margin: 10px 0 12px; padding-right: 28px; }
.modal-meta { border-top: 0; padding-top: 0; margin-bottom: 16px; }
.modal-body h4 { font-size: 15px; color: var(--pku-red); margin: 18px 0 8px; }
.modal-body p { font-size: 14.5px; color: var(--ink-soft); }
.modal-body ul { list-style: none; }
.modal-body li {
  font-size: 14.5px; color: var(--ink-soft); padding: 7px 0 7px 18px;
  position: relative; border-top: 1px dashed var(--line);
}
.modal-body li::before { content: "›"; position: absolute; left: 2px; color: var(--pku-red); font-weight: 700; }
.modal-panel .btn { margin-top: 22px; }

/* ---------- 学员风采 ---------- */
.showcase-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.shot {
  margin: 0; background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; box-shadow: var(--shadow-sm); transition: transform .25s ease, box-shadow .25s ease;
}
.shot:hover { transform: translateY(-5px); box-shadow: var(--shadow); }
.shot-media { position: relative; aspect-ratio: 4 / 3; }
.shot-media .ph {
  position: absolute; inset: 0; display: flex; align-items: center; justify-content: center;
  font-size: 46px; color: #fff;
}
.shot-media img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.ph-g1 .shot-media { background: linear-gradient(135deg, #C8102E, #7A0A1C); }
.ph-g2 .shot-media { background: linear-gradient(135deg, #B8995A, #6E5526); }
.ph-g3 .shot-media { background: linear-gradient(135deg, #2E5A88, #14304C); }
.ph-g4 .shot-media { background: linear-gradient(135deg, #4A7C59, #22402C); }
.ph-g5 .shot-media { background: linear-gradient(135deg, #6B4E9E, #37255A); }
.ph-g6 .shot-media { background: linear-gradient(135deg, #1F8A8A, #0C4B4B); }
.shot figcaption { padding: 12px 16px; font-size: 14px; color: var(--ink-soft); border-top: 1px solid var(--line); }

/* ---------- 学习收益 ---------- */
.benefits-wrap { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.benefit {
  display: flex; align-items: center; gap: 16px; background: rgba(255,255,255,.05);
  border: 1px solid rgba(255,255,255,.1); border-radius: var(--radius); padding: 22px 24px;
  font-size: 15.5px; color: rgba(255,255,255,.9);
}
.benefit strong {
  font-family: var(--serif); font-size: 26px; color: var(--pku-gold); min-width: 34px;
  font-weight: 700;
}

/* ---------- 招生报名 ---------- */
.enroll-layout { display: grid; grid-template-columns: 1.1fr .9fr; gap: 56px; align-items: start; }
.enroll-info h2 { font-family: var(--serif); font-size: clamp(28px,4vw,40px); margin: 6px 0 14px; }
.enroll-info > p { color: var(--ink-soft); font-size: 16px; margin-bottom: 26px; }
.enroll-list { list-style: none; }
.enroll-list li { display: flex; gap: 14px; padding: 14px 0; border-bottom: 1px solid var(--line); font-size: 15px; color: var(--ink-soft); }
.enroll-list li span { color: var(--pku-red); font-weight: 600; min-width: 80px; }
.steps { display: flex; gap: 10px; margin-top: 30px; flex-wrap: wrap; }
.step {
  flex: 1; min-width: 110px; background: var(--bg-alt); border-radius: 12px; padding: 16px;
  font-size: 14px; font-weight: 600; position: relative; text-align: center;
}
.step span { display: block; font-family: var(--serif); font-size: 22px; color: var(--pku-red); margin-bottom: 6px; }

.enroll-form { background: #fff; border: 1px solid var(--line); border-radius: 18px; padding: 34px 30px; box-shadow: var(--shadow); }
.enroll-form h3 { font-family: var(--serif); font-size: 22px; margin-bottom: 6px; }
.form-tip { color: var(--muted); font-size: 13px; margin-bottom: 22px; }
.enroll-form label { display: block; font-size: 14px; color: var(--ink-soft); margin-bottom: 16px; font-weight: 500; }
.enroll-form input, .enroll-form textarea {
  width: 100%; margin-top: 7px; padding: 12px 14px; border: 1px solid var(--line); border-radius: 10px;
  font-size: 15px; font-family: var(--sans); color: var(--ink); background: #FBFAF7; transition: border-color .2s, box-shadow .2s;
}
.enroll-form input:focus, .enroll-form textarea:focus { outline: none; border-color: var(--pku-red); box-shadow: 0 0 0 3px rgba(200,16,46,.12); }
.enroll-form textarea { resize: vertical; }
.form-note { font-size: 13.5px; margin-top: 14px; min-height: 18px; }
.form-note.ok { color: #2F7D4F; }
.form-note.err { color: var(--pku-red); }
.btn[disabled] { opacity: .6; cursor: not-allowed; transform: none; box-shadow: none; }

/* ---------- 报名成功页 ---------- */
.enroll-success { text-align: center; padding: 16px 4px; animation: fadeUp .5s ease; }
.success-badge {
  width: 72px; height: 72px; border-radius: 50%; margin: 0 auto 18px;
  display: flex; align-items: center; justify-content: center;
  background: rgba(47,125,79,.12); color: #2F7D4F; font-size: 38px; font-weight: 700;
  border: 2px solid rgba(47,125,79,.35);
}
.enroll-success h3 { font-family: var(--serif); font-size: 24px; margin-bottom: 12px; }
.success-main { color: var(--ink-soft); font-size: 15.5px; margin-bottom: 8px; }
.success-main strong { color: var(--pku-red); }
.success-sub { color: var(--muted); font-size: 13.5px; margin-bottom: 22px; }
@keyframes fadeUp { from { opacity: 0; transform: translateY(14px); } to { opacity: 1; transform: none; } }

/* ---------- 联系我们 ---------- */
.contact-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.contact-layout h2 { font-family: var(--serif); font-size: clamp(28px,4vw,40px); margin: 6px 0 14px; }
.contact-layout > div > p { color: var(--ink-soft); margin-bottom: 24px; }
.contact-list { list-style: none; }
.contact-list li { padding: 12px 0; border-bottom: 1px solid var(--line); font-size: 15.5px; color: var(--ink-soft); }
.contact-list li strong { display: inline-block; min-width: 84px; color: var(--ink); font-weight: 600; }
.contact-map {
  min-height: 320px; border-radius: 18px; position: relative; overflow: hidden;
  background:
    radial-gradient(120% 120% at 70% 20%, rgba(184,153,90,.25), transparent 60%),
    linear-gradient(135deg, #2E5A88, #1C3A5A);
  display: flex; align-items: center; justify-content: center;
}
.map-card {
  background: rgba(255,255,255,.94); border-radius: 14px; padding: 26px 30px; text-align: center;
  box-shadow: var(--shadow); max-width: 280px;
}
.map-pin { font-size: 34px; display: block; }
.map-card strong { font-family: var(--serif); font-size: 19px; display: block; margin: 8px 0 4px; }
.map-card em { font-style: normal; color: var(--muted); font-size: 13.5px; }

/* ---------- 页脚 ---------- */
.footer { background: var(--bg-dark); color: #CFC8BC; padding-top: 56px; }
.footer-inner { display: flex; justify-content: space-between; gap: 40px; flex-wrap: wrap; padding-bottom: 40px; }
.footer-brand { display: flex; gap: 14px; align-items: center; }
.footer-brand strong { color: #fff; font-family: var(--serif); font-size: 18px; }
.footer-brand p { font-size: 13.5px; color: #9C9488; margin-top: 4px; }
.footer-nav { display: flex; gap: 24px; flex-wrap: wrap; align-items: center; }
.footer-nav a { font-size: 14.5px; color: #CFC8BC; transition: color .2s; }
.footer-nav a:hover { color: var(--pku-gold); }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.1); padding: 18px 0; font-size: 13px; color: #807868; }

/* ---------- 滚动揭示动画 ---------- */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .7s ease, transform .7s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 980px) {
  .grid-3, .grid-4, .benefits-wrap, .showcase-grid { grid-template-columns: repeat(2, 1fr); }
  .enroll-layout, .contact-layout { grid-template-columns: 1fr; gap: 36px; }
}
@media (max-width: 720px) {
  .topbar-inner { font-size: 12px; }
  .topbar-right .topbar-item:last-child { display: none; }
  .nav-links {
    position: fixed; top: 112px; right: 16px; left: 16px; background: #fff; flex-direction: column;
    gap: 4px; padding: 16px; border-radius: 14px; box-shadow: var(--shadow); border: 1px solid var(--line);
    transform: translateY(-12px); opacity: 0; pointer-events: none; transition: .25s;
  }
  .nav-links.open { transform: none; opacity: 1; pointer-events: auto; }
  .nav-links a { padding: 12px 8px; border-bottom: 1px solid var(--line); }
  .nav-cta { display: none; }
  .nav-toggle { display: flex; }
  .grid-3, .grid-4, .benefits-wrap, .showcase-grid { grid-template-columns: 1fr; }
  .section { padding: 64px 0; }
  .hero-stats { gap: 28px; }
  .modal-panel { padding: 26px 20px 22px; }
}

/* ---------- 课程详情页入口 ---------- */
.course h3 a { color: inherit; }
.course h3 a:hover { color: var(--pku-red); }
.course-link {
  display: inline-block; margin-top: 12px;
  font-size: 13.5px; color: var(--pku-red); font-weight: 500;
}
.course-link:hover { text-decoration: underline; }

/* ---------- 招生问答（首页） ---------- */
.faq-list { max-width: 880px; margin: 0 auto; display: grid; gap: 12px; }
.faq-list details {
  background: #fff; border: 1px solid var(--line); border-radius: 12px;
  padding: 18px 22px; transition: border-color .2s, box-shadow .2s;
}
.faq-list details[open] { border-color: #DED6C8; box-shadow: var(--shadow-sm); }
.faq-list summary {
  cursor: pointer; list-style: none; font-size: 16px; font-weight: 600; color: var(--ink);
  position: relative; padding-right: 30px; line-height: 1.6;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after {
  content: "+"; position: absolute; right: 0; top: -3px;
  color: var(--pku-red); font-size: 22px; font-weight: 400; line-height: 1;
}
.faq-list details[open] summary::after { content: "–"; }
.faq-list p { margin: 12px 0 0; font-size: 14.5px; color: var(--ink-soft); line-height: 1.9; }
.faq-list p a { color: var(--pku-red); }
.faq-more { text-align: center; margin-top: 30px; }
.faq-more .btn { margin: 0 6px 10px; }
.faq-more-note { font-size: 13px; color: var(--muted); margin-top: 10px; }
.btn-ghost-dark { background: transparent; color: var(--ink); border-color: #C9C2B5; }
.btn-ghost-dark:hover { background: rgba(26, 22, 18, .05); border-color: var(--ink); }