/* =========================================================
   人艺专升本 · 企业官网
   风格参考：UI/UX Pro Max - Customer Support CRM (Flat Design)
   Palette: 专业蓝 #2563EB + 成交绿 #059669
   Typography: Fira Sans + Noto Sans SC
   ========================================================= */

:root {
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-on-primary: #ffffff;
  --color-secondary: #3b82f6;
  --color-accent: #059669;
  --color-accent-dark: #047857;
  --color-background: #f8fafc;
  --color-surface: #ffffff;
  --color-foreground: #0f172a;
  --color-muted-bg: #f1f5fd;
  --card-accent-bg: linear-gradient(135deg, #f8faff 0%, var(--color-muted-bg) 52%, #e8f0fe 100%);
  --color-muted-text: #64748b;
  --color-border: #e4ecfc;
  --color-dark: #0b1220;

  --radius-sm: 4px;
  --radius: 6px;
  --radius-lg: 8px;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
  --shadow: 0 8px 24px rgba(37, 99, 235, 0.08);
  --container: 1160px;
  --ease: 180ms ease;

  --font-sans: "Fira Sans", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-display: "Barlow Condensed", "Fira Sans", sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  color: var(--color-foreground);
  background: var(--color-background);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.skip-link {
  position: absolute;
  top: -100%;
  left: 16px;
  z-index: 200;
  padding: 10px 18px;
  background: var(--color-primary);
  color: var(--color-on-primary);
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 600;
  transition: top var(--ease);
}
.skip-link:focus {
  top: 12px;
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul { list-style: none; }

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 26px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-family: inherit;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--ease), color var(--ease), border-color var(--ease), transform var(--ease);
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn-sm { padding: 9px 18px; font-size: 14px; }
.btn-primary { background: var(--color-primary); color: var(--color-on-primary); }
.btn-primary:hover { background: var(--color-primary-dark); }
.btn-accent { background: var(--color-accent); color: #fff; }
.btn-accent:hover { background: var(--color-accent-dark); }
.btn-ghost { background: transparent; color: var(--color-primary); border-color: var(--color-border); }
.btn-ghost:hover { background: var(--color-muted-bg); }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--ease), box-shadow var(--ease);
}
.site-header.scrolled {
  border-bottom-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  gap: 20px;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand-logo { height: 38px; width: auto; display: block; }

.nav { display: flex; align-items: center; gap: 6px; }
.nav-link {
  padding: 8px 14px;
  font-size: 15px;
  font-weight: 500;
  color: var(--color-muted-text);
  border-radius: 999px;
  transition: color var(--ease), background var(--ease);
}
.nav-link:hover, .nav-link.active { color: var(--color-primary); background: var(--color-muted-bg); }
.header-cta { flex-shrink: 0; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  width: 24px; height: 2px;
  background: var(--color-foreground);
  border-radius: 2px;
  transition: transform var(--ease), opacity var(--ease);
}
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: 96px 0 88px;
  overflow: hidden;
  color: #fff;
}
.hero-media {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hero-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 35%;
}
.hero-overlay {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(105deg, rgba(37, 99, 235, 0.68) 0%, rgba(37, 99, 235, 0.42) 46%, rgba(59, 130, 246, 0.18) 72%, rgba(37, 99, 235, 0.08) 100%),
    linear-gradient(180deg, rgba(29, 78, 216, 0.15) 0%, rgba(37, 99, 235, 0.32) 100%);
}
.hero-inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  align-items: center;
  gap: 56px;
}
.eyebrow {
  display: inline-block;
  padding: 6px 14px;
  background: rgba(255, 255, 255, 0.12);
  color: #dbeafe;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 999px;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 22px;
  backdrop-filter: blur(8px);
}
.hero .eyebrow {
  background: rgba(255, 255, 255, 0.12);
  color: #dbeafe;
  border-color: rgba(255, 255, 255, 0.18);
  text-shadow: 0 1px 4px rgba(15, 23, 42, 0.3);
}
.hero-title {
  font-size: 52px;
  line-height: 1.15;
  font-weight: 700;
  letter-spacing: -.5px;
  color: #fff;
  text-shadow:
    0 1px 2px rgba(15, 23, 42, 0.45),
    0 4px 18px rgba(15, 23, 42, 0.38);
}
.hero-title .hl {
  color: #eff6ff;
  text-shadow:
    0 1px 2px rgba(15, 23, 42, 0.45),
    0 4px 18px rgba(15, 23, 42, 0.38),
    0 0 24px rgba(59, 130, 246, 0.35);
}
.hero-sub {
  margin: 22px 0 30px;
  font-size: 17px;
  color: rgba(239, 246, 255, 0.92);
  max-width: 520px;
  text-shadow:
    0 1px 3px rgba(15, 23, 42, 0.5),
    0 3px 14px rgba(15, 23, 42, 0.35);
}
.hero-contact {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  width: 100%;
  gap: 0;
  padding: 0;
  background: transparent;
  border: none;
  box-shadow: none;
  backdrop-filter: none;
}
.hero-phone {
  display: flex;
  align-items: center;
  gap: 14px;
  justify-self: center;
  min-width: 0;
  padding: 2px 0;
  background: transparent;
  border: none;
  backdrop-filter: none;
  transition: opacity var(--ease);
}
}
.hero-phone:hover { opacity: 0.92; }
.hero-phone svg {
  width: 30px;
  height: 30px;
  flex-shrink: 0;
  color: #fff;
  filter: drop-shadow(0 1px 3px rgba(15, 23, 42, 0.35));
}
.hero-phone-text { display: flex; flex-direction: column; gap: 4px; min-width: 0; }
.hero-phone-label {
  font-size: 13px;
  font-weight: 500;
  color: rgba(239, 246, 255, 0.85);
  text-shadow: 0 1px 3px rgba(15, 23, 42, 0.4);
}
.hero-phone-num {
  font-size: 24px;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.02em;
  white-space: nowrap;
  text-shadow: 0 1px 3px rgba(15, 23, 42, 0.45);
}
.hero-contact-divider {
  width: 1px;
  height: 76px;
  margin: 0 18px;
  flex-shrink: 0;
  background: rgba(255, 255, 255, 0.22);
}
.hero-qr {
  margin: 0;
  justify-self: center;
  flex-shrink: 0;
  text-align: center;
}
.hero-qr img {
  width: 84px;
  height: 84px;
  display: block;
  border-radius: var(--radius);
  border: none;
  padding: 0;
  background: transparent;
  object-fit: contain;
  box-shadow: none;
}
.hero-qr figcaption {
  margin-top: 6px;
  font-size: 12px;
  font-weight: 500;
  color: rgba(239, 246, 255, 0.9);
  text-shadow: 0 1px 4px rgba(15, 23, 42, 0.4);
  white-space: nowrap;
}

.hero-aside {
  display: flex;
  flex-direction: column;
  gap: 28px;
  align-items: stretch;
  justify-content: center;
}

.hero-mobile-visual {
  display: none;
  margin: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.28);
  box-shadow: 0 16px 40px rgba(15, 23, 42, 0.28);
}
.hero-mobile-visual img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  object-position: center 35%;
  display: block;
}

.stat-card {
  width: 100%;
  max-width: 380px;
  padding: 0;
  background: transparent;
  border: none;
  box-shadow: none;
  backdrop-filter: none;
}
.stat-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0 28px;
}
.stat-row + .stat-row { margin-top: 28px; }
.stat {
  padding: 0;
  text-align: center;
}
.stat-num {
  font-size: 32px;
  font-weight: 800;
  color: #fff;
  line-height: 1;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
  text-shadow:
    0 1px 3px rgba(15, 23, 42, 0.45),
    0 4px 16px rgba(15, 23, 42, 0.32);
}
.stat-row:nth-child(2) .stat-num { color: #bbf7d0; }
.stat-label {
  margin-top: 8px;
  font-size: 13px;
  font-weight: 500;
  color: rgba(239, 246, 255, 0.88);
  line-height: 1.35;
  text-shadow: 0 1px 4px rgba(15, 23, 42, 0.4);
}

/* ---------- 信任条 ---------- */
.trust-bar { border-top: 1px solid var(--color-border); border-bottom: 1px solid var(--color-border); background: var(--color-surface); }
.trust-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-around;
  gap: 16px 24px;
  padding: 22px 24px;
}
.trust-item {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  color: var(--color-foreground);
  font-size: 15px;
}
.trust-item::before {
  content: "";
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--color-accent);
}

/* ---------- 通用 section ---------- */
.section { padding: 84px 0; }
.section-alt { background: var(--color-surface); }
.section-head { margin-bottom: 46px; }
.section-head.center { text-align: center; }
.section-head.center .section-desc { margin-left: auto; margin-right: auto; }
.section-eyebrow {
  display: inline-block;
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 12px;
}
.section-eyebrow.light { color: #93b4fb; }
.section-title { font-size: 30px; font-weight: 700; line-height: 1.25; letter-spacing: -.3px; }
.section-title.light { color: #fff; }
.section-desc { margin-top: 14px; font-size: 16px; color: var(--color-muted-text); max-width: 620px; }

/* ---------- 关于我们 ---------- */
.about-grid { display: grid; grid-template-columns: 1.3fr 1fr; gap: 48px; align-items: start; }
.entity-lead { max-width: 720px; margin-top: 12px; text-align: left; }
.entity-facts {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-bottom: 40px;
  padding: 24px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}
.entity-fact { display: flex; flex-direction: column; gap: 4px; }
.entity-fact dt {
  font-size: 13px;
  font-weight: 600;
  color: var(--color-muted-text);
  letter-spacing: 0.02em;
}
.entity-fact dd { font-size: 15px; font-weight: 500; color: var(--color-foreground); line-height: 1.5; }
.about-text p { font-size: 16px; color: var(--color-muted-text); margin-bottom: 16px; }
.about-text b { color: var(--color-foreground); }
.feature-list { margin-top: 24px; display: grid; gap: 14px; }
.feature-list li {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 15px;
  font-weight: 500;
  color: var(--color-foreground);
}
.feature-list svg {
  width: 22px; height: 22px;
  flex-shrink: 0;
  padding: 3px;
  color: #fff;
  background: var(--color-accent);
  border-radius: 50%;
}

/* ---------- 宣传册素材展示 ---------- */
.showcase-figure {
  margin: 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  box-shadow: var(--shadow-sm);
}
.showcase-figure img {
  width: 100%;
  height: auto;
  display: block;
}
.showcase-figure figcaption {
  padding: 12px 16px;
  font-size: 14px;
  color: var(--color-muted-text);
  text-align: center;
  border-top: 1px solid var(--color-border);
  background: var(--color-muted-bg);
}

.brand-strength {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
  margin-top: 56px;
  padding-top: 56px;
  border-top: 1px solid var(--color-border);
}
.brand-strength-title {
  font-size: 24px;
  font-weight: 700;
  margin: 10px 0 14px;
}
.brand-strength-text p {
  color: var(--color-muted-text);
  margin-bottom: 24px;
  line-height: 1.7;
}
.brand-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}
.brand-stat {
  padding: 16px 14px;
  background: var(--card-accent-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  text-align: center;
}
.brand-stat-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 8px;
  color: var(--color-primary);
}
.brand-stat-icon svg {
  width: 22px;
  height: 22px;
}
.brand-stat b {
  display: block;
  font-size: 22px;
  color: var(--color-primary);
  margin-bottom: 4px;
}
.brand-stat span { font-size: 13px; color: var(--color-muted-text); }

.camp-banner {
  margin-bottom: 32px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow);
}
.camp-banner img { width: 100%; height: auto; display: block; }

.camp-split {
  display: grid;
  grid-template-columns: 1fr 1.1fr;
  gap: 32px;
  align-items: start;
  margin-bottom: 32px;
}
.camp-features { display: grid; gap: 18px; }
.camp-features li {
  padding: 18px 20px;
  background: var(--card-accent-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}
.camp-features h3 {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 16px;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 8px;
}
.camp-features h3 svg {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
}
.camp-features p {
  font-size: 14px;
  color: var(--color-muted-text);
  line-height: 1.65;
}

.media-duo {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.system-showcase,
.teacher-showcase {
  display: grid;
  gap: 24px;
  margin-top: 40px;
}
.system-showcase,
.teacher-showcase { grid-template-columns: 1fr 1fr; }

.success-showcase {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.showcase-slogan {
  margin-top: 28px;
  text-align: center;
  font-size: 17px;
  font-weight: 600;
  color: var(--color-primary);
}

.about-highlights { display: grid; gap: 16px; }
.highlight {
  position: relative;
  overflow: hidden;
  background: var(--card-accent-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 22px 24px;
  transition: transform var(--ease), box-shadow var(--ease), border-color var(--ease);
}
.highlight::before {
  content: attr(data-step);
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-display);
  font-size: clamp(64px, 9vw, 88px);
  font-weight: 800;
  line-height: 0.9;
  color: var(--color-primary);
  opacity: 0.08;
  pointer-events: none;
  letter-spacing: 0.04em;
}
.highlight:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow);
  border-color: rgba(37, 99, 235, 0.22);
}
.highlight:hover::before { opacity: 0.12; }
.highlight h3 {
  position: relative;
  z-index: 1;
  font-size: 18px;
  margin: 0 0 6px;
}
.highlight p {
  position: relative;
  z-index: 1;
  font-size: 14px;
  color: var(--color-muted-text);
  line-height: 1.65;
}

/* ---------- 课程卡片 ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.course-card {
  position: relative;
  overflow: hidden;
  display: block;
  background: var(--card-accent-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px 96px 24px 22px;
  transition: transform var(--ease), box-shadow var(--ease), border-color var(--ease);
}
.course-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
  border-color: rgba(37, 99, 235, 0.22);
}
.course-icon {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  margin-bottom: 0;
  width: auto;
  height: auto;
  display: block;
  background: transparent;
  color: var(--color-primary);
  border-radius: 0;
  opacity: 0.14;
  pointer-events: none;
  z-index: 0;
}
.course-icon svg {
  width: 72px;
  height: 72px;
  stroke-width: 1.5;
}
.course-card h3 {
  position: relative;
  z-index: 1;
  font-size: 19px;
  margin-bottom: 8px;
  line-height: 1.35;
}
.course-card p {
  position: relative;
  z-index: 1;
  font-size: 15px;
  color: var(--color-muted-text);
  line-height: 1.6;
}

/* ---------- 班型介绍 ---------- */
.class-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  max-width: 760px;
  margin: 0 auto 26px;
}
.class-stat {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 18px 12px;
  text-align: center;
  box-shadow: var(--shadow-sm);
}
.class-stat b { display: block; font-size: 26px; font-weight: 800; color: var(--color-primary); line-height: 1; }
.class-stat span { display: block; margin-top: 8px; font-size: 13px; color: var(--color-muted-text); }

.class-subjects-note {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  max-width: 760px;
  margin: 0 auto 40px;
  padding: 14px 20px;
  background: var(--color-muted-bg);
  border: 1px dashed var(--color-border);
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  color: var(--color-primary);
  text-align: center;
}
.class-subjects-note svg { width: 18px; height: 18px; flex-shrink: 0; }

.class-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
}
.class-card {
  position: relative;
  display: flex;
  flex-direction: column;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 26px 24px 24px;
  box-shadow: var(--shadow-sm);
  transition: transform var(--ease), box-shadow var(--ease), border-color var(--ease);
}
.class-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
  border-color: var(--color-secondary);
}
.class-card--featured {
  border-color: #fbbf24;
  box-shadow: 0 14px 40px rgba(234, 88, 12, 0.14);
  background: linear-gradient(180deg, #fffbeb 0%, var(--color-surface) 42%);
}
.featured-tag {
  position: absolute;
  top: 0; right: 24px;
  transform: translateY(-50%);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 999px;
  background: linear-gradient(135deg, #f59e0b 0%, #ea580c 100%);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  box-shadow: 0 6px 16px rgba(234, 88, 12, 0.3);
}
.featured-tag svg { width: 14px; height: 14px; }

.class-card-top { display: flex; align-items: flex-start; gap: 12px; margin-bottom: 14px; }
.level-badge {
  flex-shrink: 0;
  padding: 5px 10px;
  border-radius: var(--radius-sm);
  font-size: 12px;
  font-weight: 700;
  line-height: 1;
}
.lv-l1 { background: #eff6ff; color: #2563eb; }
.lv-l2 { background: #ecfdf5; color: #059669; }
.lv-l3 { background: #fff7ed; color: #ea580c; }
.lv-l4 { background: #fef3c7; color: #b45309; }
.lv-l5 { background: #fce7f3; color: #be185d; }
.lv-l6 { background: #ede9fe; color: #6d28d9; }
.lv-l7 { background: #fef2f2; color: #dc2626; }
.class-card-title h3 {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 19px;
  font-weight: 700;
  line-height: 1.3;
}
.hot-badge {
  display: inline-block;
  margin-right: 6px;
  padding: 2px 7px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, #f59e0b 0%, #ea580c 100%);
  color: #fff;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: .5px;
}
.class-tag { display: block; margin-top: 4px; font-size: 13px; color: var(--color-muted-text); }
.class-desc { font-size: 14px; color: var(--color-foreground); margin-bottom: 18px; }

.class-price {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding-bottom: 18px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--color-border);
}
.price-promo { font-size: 12px; font-weight: 600; color: #ea580c; }
.price-row { display: flex; align-items: baseline; }
.price-cur { font-size: 18px; font-weight: 700; color: #ea580c; margin-right: 2px; }
.price-num { font-size: 34px; font-weight: 800; color: #ea580c; line-height: 1; }
.price-old { font-size: 13px; color: var(--color-muted-text); text-decoration: line-through; }

.class-feats { display: grid; gap: 10px; margin-bottom: 18px; }
.class-feats li {
  position: relative;
  padding-left: 20px;
  font-size: 13.5px;
  color: var(--color-muted-text);
  line-height: 1.5;
}
.class-feats li::before {
  content: "";
  position: absolute;
  left: 2px; top: 8px;
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--color-primary);
}
.class-hours {
  margin-bottom: 20px;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  background: rgba(37, 99, 235, 0.06);
  font-size: 13px;
  font-weight: 600;
  color: var(--color-primary-dark);
  line-height: 1.5;
}
.class-cta { margin-top: auto; width: 100%; }

.class-foot-note {
  margin-top: 34px;
  text-align: center;
  font-size: 14px;
  color: var(--color-muted-text);
}

/* ---------- 商务合作 ---------- */
.coop-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; }

/* ---------- 常见问题（GEO） ---------- */
.faq-list { max-width: 820px; margin: 0 auto; display: grid; gap: 12px; }
.faq-item {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: box-shadow var(--ease), border-color var(--ease);
}
.faq-item[open] {
  box-shadow: var(--shadow-sm);
  border-color: rgba(37, 99, 235, 0.18);
}
.faq-item summary {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 18px 22px;
  cursor: pointer;
  list-style: none;
  user-select: none;
  transition: background var(--ease);
}
.faq-item[open] summary { background: rgba(37, 99, 235, 0.04); }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+";
  margin-left: auto;
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--color-muted-bg);
  color: var(--color-primary);
  font-size: 18px;
  font-weight: 600;
  line-height: 1;
  transition:
    transform 0.35s cubic-bezier(0.4, 0, 0.2, 1),
    background var(--ease),
    color var(--ease);
}
.faq-item[open] summary::after {
  content: "−";
  background: var(--color-primary);
  color: #fff;
  transform: rotate(180deg);
}
.faq-item summary h3 {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--color-foreground);
  transition: color var(--ease);
}
.faq-item[open] summary h3 { color: var(--color-primary); }
.faq-answer-wrap {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}
.faq-item[open] .faq-answer-wrap { grid-template-rows: 1fr; }
.faq-answer {
  overflow: hidden;
  min-height: 0;
  padding: 0 22px;
  border-top: 1px solid transparent;
  opacity: 0;
  transform: translateY(-6px);
  transition:
    opacity 0.22s ease,
    transform 0.28s cubic-bezier(0.4, 0, 0.2, 1),
    padding 0.38s cubic-bezier(0.4, 0, 0.2, 1),
    border-color var(--ease);
}
.faq-item[open] .faq-answer {
  padding: 0 22px 20px;
  border-top-color: var(--color-border);
  opacity: 1;
  transform: translateY(0);
  transition:
    opacity 0.32s ease 0.08s,
    transform 0.35s cubic-bezier(0.4, 0, 0.2, 1) 0.06s,
    padding 0.4s cubic-bezier(0.4, 0, 0.2, 1),
    border-color var(--ease);
}
.faq-answer p {
  font-size: 15px;
  color: var(--color-muted-text);
  line-height: 1.7;
  margin-top: 16px;
}
.faq-answer p:first-child { margin-top: 16px; }
.faq-answer ul {
  margin: 12px 0;
  padding-left: 20px;
  list-style: disc;
  display: grid;
  gap: 8px;
}
.faq-answer li { font-size: 15px; color: var(--color-muted-text); line-height: 1.6; }
.faq-answer strong { color: var(--color-foreground); }
.faq-answer a { color: var(--color-primary); text-decoration: underline; text-underline-offset: 2px; }

.coop-card {
  position: relative;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 32px 28px;
  overflow: hidden;
  transition: transform var(--ease), box-shadow var(--ease);
}
.coop-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.coop-index { font-size: 20px; font-weight: 700; color: var(--color-foreground); margin-bottom: 12px; }
.coop-card p { font-size: 15px; color: var(--color-muted-text); }

/* ---------- SaaS 平台（深色） ---------- */
.section-dark { background: var(--color-dark); }
.saas-inner { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 56px; align-items: center; }
.saas-desc { margin: 20px 0 28px; font-size: 16px; color: #a7b4c9; }
.saas-scenarios {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
  padding: 32px;
}
.saas-scenarios h3 { color: #fff; font-size: 18px; margin-bottom: 18px; }
.saas-scenarios ul { display: grid; gap: 14px; }
.saas-scenarios li {
  display: flex;
  align-items: center;
  gap: 12px;
  color: #e2e8f0;
  font-size: 15px;
  font-weight: 500;
}
.saas-scenarios svg { width: 20px; height: 20px; color: var(--color-accent); flex-shrink: 0; }
.saas-note {
  margin-top: 22px;
  padding-top: 18px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 13px;
  color: #7c8aa3;
}

/* ---------- 联系我们 ---------- */
.contact-card {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 40px;
  align-items: center;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 48px;
  box-shadow: var(--shadow);
}
.contact-lead { margin: 16px 0 26px; color: var(--color-muted-text); font-size: 16px; }
.contact-list { display: grid; gap: 18px; }
.contact-list li { display: flex; align-items: center; gap: 14px; }
.contact-list svg {
  width: 42px; height: 42px;
  padding: 10px;
  flex-shrink: 0;
  color: var(--color-primary);
  background: var(--color-muted-bg);
  border-radius: var(--radius-sm);
}
.c-label { display: block; font-size: 13px; color: var(--color-muted-text); }
.contact-list a, .contact-list div span:last-child, .contact-list address { font-size: 16px; font-weight: 600; color: var(--color-foreground); }
.contact-list address { font-style: normal; }
.contact-list a:hover { color: var(--color-primary); }
.contact-qr { text-align: center; }
.contact-qr img {
  width: 200px; height: 200px;
  margin: 0 auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 8px;
  background: #fff;
  object-fit: contain;
}
.contact-qr p { margin-top: 14px; font-size: 14px; color: var(--color-muted-text); }
.contact-qr-phone {
  display: inline-block;
  margin-top: 8px;
  font-size: 18px;
  font-weight: 700;
  color: var(--color-primary);
}
.contact-qr-phone:hover { color: var(--color-primary-dark); }

/* ---------- 页脚 ---------- */
.site-footer { background: var(--color-dark); color: #cbd5e1; }
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 24px;
  padding: 48px 24px;
}
.footer-logo-link {
  display: inline-flex;
  padding: 9px 14px;
}
.footer-logo { height: 30px; width: auto; display: block; }
.footer-brand p { margin-top: 14px; font-size: 14px; color: #7c8aa3; max-width: 320px; }
.footer-nav { display: flex; flex-wrap: wrap; gap: 8px 24px; }
.footer-nav a { font-size: 15px; color: #cbd5e1; transition: color var(--ease); }
.footer-nav a:hover { color: #fff; }
.footer-bottom { border-top: 1px solid rgba(255, 255, 255, 0.08); }
.footer-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px 24px;
  padding-top: 20px;
  padding-bottom: 20px;
  font-size: 13px;
  color: #7c8aa3;
}
.footer-meta a { color: #94a3b8; transition: color var(--ease); }
.footer-meta a:hover { color: #fff; }
.footer-links {
  display: inline-flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px 16px;
}
.footer-links a { white-space: nowrap; }

/* ---------- 回到顶部 ---------- */
.back-top {
  position: fixed;
  right: 26px;
  bottom: 26px;
  width: 46px; height: 46px;
  display: grid; place-items: center;
  background: var(--color-primary);
  color: #fff;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity var(--ease), transform var(--ease), background var(--ease);
  box-shadow: var(--shadow);
  z-index: 90;
}
.back-top svg { width: 22px; height: 22px; }
.back-top:hover { background: var(--color-primary-dark); }
.back-top.show { opacity: 1; visibility: visible; transform: translateY(0); }

/* ---------- 进场动画 ---------- */
.reveal { opacity: 0; transform: translateY(24px); transition: opacity .6s ease, transform .6s ease; }
.reveal.visible { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .hero-inner { grid-template-columns: 1fr; gap: 28px; }
  .hero-mobile-visual { display: block; }
  .hero-img { object-position: center 28%; }
  .hero-overlay {
    background:
      linear-gradient(180deg, rgba(37, 99, 235, 0.78) 0%, rgba(37, 99, 235, 0.5) 55%, rgba(59, 130, 246, 0.28) 100%),
      linear-gradient(105deg, rgba(29, 78, 216, 0.45) 0%, rgba(37, 99, 235, 0.2) 100%);
  }
  .hero-aside { gap: 24px; }
  .hero-contact-divider {
    height: 72px;
    margin: 0 12px;
  }
  .hero-phone { gap: 10px; }
  .stat-card { max-width: 100%; }
  .stat-num { font-size: 28px; }
  .stat-row + .stat-row { margin-top: 22px; }
  .brand-strength .showcase-figure,
  .camp-split .showcase-figure { order: -1; }
  #about .container {
    display: flex;
    flex-direction: column;
  }
  #about .section-head { order: 1; }
  #about .brand-strength {
    order: 2;
    margin-top: 28px;
    padding-top: 0;
    border-top: none;
  }
  #about .entity-facts {
    order: 3;
    margin-top: 32px;
    margin-bottom: 32px;
  }
  #about .about-grid { order: 4; }
  #courses .container {
    display: flex;
    flex-direction: column;
  }
  #courses .section-head { order: 1; }
  #courses .system-showcase { order: 2; margin-top: 0; }
  #courses .card-grid { order: 3; }
  .about-grid,
  .entity-facts,
  .brand-strength,
  .camp-split,
  .media-duo,
  .system-showcase,
  .teacher-showcase,
  .success-showcase,
  .contact-card { grid-template-columns: 1fr; }
  .brand-stats { grid-template-columns: repeat(2, 1fr); }
  .card-grid,
  .coop-grid,
  .class-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-card { padding: 36px 28px; }
  .showcase-figure { margin-bottom: 4px; }
  .system-showcase { gap: 20px; }
  .card-grid { gap: 12px; }
  .course-card { padding: 16px 88px 16px 18px; }
  .course-icon svg { width: 64px; height: 64px; }
  .course-card h3 { font-size: 17px; margin-bottom: 6px; }
  .course-card p { font-size: 14px; line-height: 1.55; }
}

@media (max-width: 1100px) and (min-width: 961px) {
  .class-grid { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 720px) {
  .nav, .header-cta { display: none; }
  .nav-toggle { display: flex; }
  .nav.open {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    position: absolute;
    top: 72px;
    left: 0; right: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    padding: 12px 24px 18px;
    box-shadow: var(--shadow);
  }
  .nav.open .nav-link { padding: 12px 14px; }
  .hero { padding: 64px 0 48px; min-height: auto; }
  .hero-title { font-size: 34px; }
  .hero-sub { font-size: 15px; margin: 16px 0 22px; }
  .hero-contact-divider {
    height: 64px;
    margin: 0 10px;
  }
  .hero-phone { gap: 8px; }
  .hero-phone svg { width: 26px; height: 26px; }
  .hero-phone-label { font-size: 12px; }
  .hero-phone-num {
    font-size: clamp(15px, 4vw, 18px);
    letter-spacing: 0;
  }
  .hero-qr img { width: 72px; height: 72px; }
  .hero-qr figcaption { font-size: 11px; margin-top: 4px; }
  .hero-mobile-visual { margin-top: 4px; }
  .section-eyebrow { font-size: 15px; }
  .section-title { font-size: 24px; }
  .section { padding: 56px 0; }
  .hero-overlay {
    background:
      linear-gradient(180deg, rgba(37, 99, 235, 0.85) 0%, rgba(37, 99, 235, 0.62) 100%);
  }
  .camp-banner { margin-bottom: 24px; }
  .camp-features li { padding: 16px 18px; }
  .media-duo { gap: 16px; }
  .card-grid, .coop-grid, .class-grid { grid-template-columns: 1fr; }
  .brand-stats { grid-template-columns: 1fr 1fr; }
  .success-showcase { grid-template-columns: 1fr; gap: 16px; }
  .teacher-showcase { gap: 16px; }
  .class-stats { grid-template-columns: repeat(2, 1fr); }
  .class-subjects-note { text-align: left; }
  .footer-inner { flex-direction: column; align-items: flex-start; }
  .footer-meta {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 10px;
  }
  .footer-links { justify-content: center; }
}

@media (prefers-reduced-motion: reduce) {
  * { scroll-behavior: auto !important; transition: none !important; }
  .reveal { opacity: 1; transform: none; }
}