/* ========================================
   CSS 变量定义
   ======================================== */
:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --primary-light: #818cf8;
  --dark: #0f172a;
  --dark-2: #1e293b;
  --dark-3: #334155;
  --gray: #64748b;
  --light: #f1f5f9;
  --light-2: #e2e8f0;
  --white: #ffffff;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #a78bfa 100%);
  --gradient-dark: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
  --shadow: 0 1px 3px rgba(0,0,0,0.1);
  --shadow-md: 0 4px 6px rgba(0,0,0,0.07);
  --shadow-lg: 0 10px 25px rgba(0,0,0,0.1);
  --shadow-xl: 0 20px 50px rgba(0,0,0,0.12);
  --radius: 12px;
  --radius-lg: 16px;
  --transition: all 0.3s ease;
}

/* ========================================
   全局样式
   ======================================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background: var(--light);
  color: var(--dark);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  text-decoration: none;
  color: inherit;
}

ul {
  list-style: none;
}

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

/* ========================================
   按钮样式
   ======================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.95rem;
  cursor: pointer;
  transition: var(--transition);
  border: none;
}

.btn-primary {
  background: var(--gradient);
  color: var(--white);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--white);
  color: var(--white);
}

.btn-outline:hover {
  background: var(--white);
  color: var(--dark);
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.05rem;
}

.btn-block {
  width: 100%;
  justify-content: center;
}

/* ========================================
   导航栏
   ======================================== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: var(--transition);
  background: transparent;
}

.navbar.scrolled {
  background: rgba(15, 23, 42, 0.95);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: var(--shadow-md);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--white);
}

.logo-icon {
  width: 32px;
  height: 32px;
  background: var(--gradient);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--white);
  font-size: 1rem;
}

.highlight {
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  gap: 8px;
}

.nav-links a {
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.7);
  transition: var(--transition);
}

.nav-links a:hover {
  background: rgba(255, 255, 255, 0.1);
  color: var(--white);
}

.nav-short {
  display: none;
}

.nav-links a.nav-highlight {
  background: var(--gradient);
  color: var(--white);
  font-weight: 600;
  padding: 8px 18px;
  border-radius: 50px;
  box-shadow: 0 2px 10px rgba(99, 102, 241, 0.3);
}

.nav-links a.nav-highlight:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 15px rgba(99, 102, 241, 0.5);
}

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 4px;
}

.hamburger span {
  width: 24px;
  height: 2px;
  background: var(--white);
  border-radius: 2px;
  transition: var(--transition);
}

.hamburger.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
}

.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg) translate(7px, -6px);
}

/* ========================================
   Hero 区域
   ======================================== */
.hero {
  min-height: 100vh;
  background: linear-gradient(135deg, #0f172a 0%, #1e1b4b 50%, #312e81 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: var(--white);
  padding: 120px 24px 80px;
  position: relative;
  overflow: hidden;
}

.hero-particles {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  pointer-events: none;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  background: rgba(99, 102, 241, 0.2);
  border-radius: 50px;
  padding: 6px 20px;
  font-size: 0.85rem;
  margin-bottom: 24px;
  border: 1px solid rgba(99, 102, 241, 0.3);
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 900;
  line-height: 1.15;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}

.hero-title .gradient-text {
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 1.15rem;
  color: rgba(255, 255, 255, 0.75);
  max-width: 640px;
  margin: 0 auto 40px;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 60px;
}

.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 48px;
}

.stat-item {
  text-align: center;
}

.stat-number {
  font-size: 2.2rem;
  font-weight: 800;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-label {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.6);
}

/* ========================================
   Section 通用样式
   ======================================== */
.section {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-tag {
  display: inline-block;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  font-weight: 700;
  font-size: 0.85rem;
  letter-spacing: 2px;
  margin-bottom: 12px;
}

.section-title {
  font-size: 2.5rem;
  font-weight: 900;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
  color: var(--dark);
}

.section-desc {
  font-size: 1.05rem;
  color: var(--gray);
  max-width: 600px;
  margin: 0 auto;
}

/* ========================================
   焦虑引导区域 (Anxiety)
   ======================================== */
.anxiety {
  background: var(--white);
}

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

.anxiety-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 32px 28px;
  border-left: 4px solid var(--danger);
  box-shadow: var(--shadow-md);
  transition: var(--transition);
}

.anxiety-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.anxiety-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: rgba(239, 68, 68, 0.1);
  color: var(--danger);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 16px;
}

.anxiety-card h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--dark);
}

.anxiety-card p {
  color: var(--gray);
  font-size: 0.9rem;
  line-height: 1.7;
}

.crisis-banner {
  background: var(--gradient-dark);
  color: var(--white);
  border-radius: var(--radius-lg);
  padding: 48px;
  margin-top: 48px;
  text-align: center;
}

.crisis-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 60px;
  margin: 32px 0;
}

.crisis-stat {
  text-align: center;
}

.crisis-number {
  font-size: 2.8rem;
  font-weight: 900;
  background: linear-gradient(135deg, #f59e0b 0%, #fbbf24 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.crisis-label {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
}

.turning-point {
  background: var(--gradient);
  border-radius: var(--radius-lg);
  padding: 40px;
  margin-top: 32px;
  text-align: center;
}

.turning-point h3 {
  color: var(--white);
  font-size: 1.5rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.turning-point p {
  color: rgba(255, 255, 255, 0.85);
  font-size: 1rem;
}

/* ========================================
   课程区域
   ======================================== */
.courses {
  background: var(--light);
}

.course-filters {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 10px 24px;
  border-radius: 50px;
  border: 1px solid var(--light-2);
  background: var(--white);
  color: var(--gray);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
}

.filter-btn.active,
.filter-btn:hover {
  background: var(--gradient);
  color: var(--white);
  border: none;
}

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

.course-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--light-2);
  transition: var(--transition);
}

.course-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-xl);
}

.course-card.hidden {
  display: none;
}

.course-header {
  padding: 28px 28px 20px;
}

.course-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: var(--gradient);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 16px;
}

.course-tag {
  display: inline-block;
  background: rgba(99, 102, 241, 0.1);
  color: var(--primary);
  padding: 4px 12px;
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 600;
}

.course-header h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin: 12px 0 8px;
  color: var(--dark);
}

.course-header p {
  color: var(--gray);
  font-size: 0.85rem;
  line-height: 1.6;
}

.course-body {
  padding: 0 28px 28px;
}

.course-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 6px 0;
  font-size: 0.85rem;
  color: var(--gray);
}

.course-features li i {
  color: var(--success);
  font-size: 0.75rem;
}

.course-footer {
  padding: 20px 28px;
  border-top: 1px solid var(--light-2);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.course-price {
  font-size: 1.3rem;
  font-weight: 800;
  color: var(--primary);
}

.course-meta span {
  color: var(--gray);
  font-size: 0.8rem;
  display: flex;
  align-items: center;
  gap: 5px;
}

/* ========================================
   关于我们
   ======================================== */
.about {
  background: var(--white);
}

.about-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 40px;
}

.about-card {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.05) 0%, rgba(139, 92, 246, 0.05) 100%);
  border-radius: var(--radius-lg);
  padding: 40px;
  border: 1px solid var(--light-2);
}

.about-icon {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  background: var(--gradient);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 20px;
}

.about-card h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--dark);
}

.about-card p {
  color: var(--gray);
  line-height: 1.8;
}

/* ========================================
   师资力量
   ======================================== */
.faculty-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.faculty-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  border: 1px solid var(--light-2);
  transition: var(--transition);
}

.faculty-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.faculty-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--gradient);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  font-weight: 800;
  margin: 0 auto 16px;
}

.faculty-card h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 4px;
  color: var(--dark);
}

.faculty-role {
  color: var(--primary);
  font-size: 0.8rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.faculty-card > p {
  color: var(--gray);
  font-size: 0.85rem;
  line-height: 1.6;
}

/* ========================================
   课程安排
   ======================================== */
.schedule {
  background: var(--white);
}

.schedule-table-wrapper {
  overflow-x: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--light-2);
  box-shadow: var(--shadow-md);
}

table {
  width: 100%;
  border-collapse: collapse;
  min-width: 600px;
}

th {
  background: var(--gradient);
  color: var(--white);
  padding: 16px 24px;
  font-size: 0.85rem;
  font-weight: 600;
  text-align: left;
}

td {
  padding: 14px 24px;
  font-size: 0.9rem;
  border-bottom: 1px solid var(--light-2);
}

tr:hover {
  background: var(--light);
}

.schedule-tag {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 600;
}

.tag-beginner {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success);
}

.tag-intermediate {
  background: rgba(99, 102, 241, 0.1);
  color: var(--primary);
}

.tag-advanced {
  background: rgba(245, 158, 11, 0.1);
  color: var(--warning);
}

/* ========================================
   学习等级
   ======================================== */
.levels {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 60px;
}

.level-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  text-align: center;
  border: 1px solid var(--light-2);
  transition: var(--transition);
}

.level-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.level-intermediate {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

.level-badge {
  display: inline-block;
  padding: 6px 20px;
  border-radius: 50px;
  font-size: 0.8rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.badge-beginner {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success);
}

.badge-intermediate {
  background: rgba(99, 102, 241, 0.1);
  color: var(--primary);
}

.badge-advanced {
  background: rgba(245, 158, 11, 0.1);
  color: var(--warning);
}

.level-card h4 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--dark);
}

.level-card p {
  color: var(--gray);
  font-size: 0.9rem;
  line-height: 1.7;
}

/* ========================================
   学习方式
   ======================================== */
.learning-modes {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.mode-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  border: 1px solid var(--light-2);
  transition: var(--transition);
}

.mode-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.mode-icon {
  width: 60px;
  height: 60px;
  border-radius: 16px;
  background: var(--gradient);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin: 0 auto 16px;
}

.mode-card h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--dark);
}

.mode-card p {
  color: var(--gray);
  font-size: 0.85rem;
  line-height: 1.6;
}

/* ========================================
   OpenClaw 专区
   ======================================== */
.openclaw-section {
  background: linear-gradient(135deg, #0f172a 0%, #1e1b4b 100%);
  color: var(--white);
}

.oc-intro-highlight {
  background: rgba(99, 102, 241, 0.1);
  border-radius: var(--radius-lg);
  padding: 40px;
  border: 1px solid rgba(99, 102, 241, 0.3);
  margin-bottom: 60px;
}

.oc-intro-highlight h3 {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 12px;
}

.oc-intro-highlight p {
  color: rgba(255, 255, 255, 0.8);
  line-height: 1.8;
}

.oc-capabilities {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 60px;
}

.oc-cap-item {
  background: rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-lg);
  padding: 28px 20px;
  text-align: center;
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.oc-cap-icon {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: var(--gradient);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  margin: 0 auto 12px;
}

.oc-cap-item h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.oc-cap-item p {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.8rem;
}

.oc-course-block {
  background: rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-lg);
  padding: 36px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  margin-bottom: 24px;
}

.oc-course-header {
  margin-bottom: 24px;
}

.oc-level-badge {
  display: inline-block;
  padding: 4px 14px;
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.oc-badge-beginner {
  background: rgba(16, 185, 129, 0.2);
  color: #34d399;
}

.oc-badge-intermediate {
  background: rgba(99, 102, 241, 0.2);
  color: #818cf8;
}

.oc-badge-advanced {
  background: rgba(245, 158, 11, 0.2);
  color: #fbbf24;
}

.oc-course-header h4 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.oc-course-subtitle {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
}

.oc-course-content {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.oc-module {
  background: rgba(255, 255, 255, 0.05);
  border-radius: var(--radius);
  padding: 20px;
}

.oc-module h5 {
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.oc-module li {
  padding: 6px 0;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.75);
  padding-left: 16px;
  position: relative;
}

.oc-module li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 6px;
  height: 6px;
  background: var(--primary-light);
  border-radius: 50%;
}

.oc-course-meta {
  display: flex;
  gap: 24px;
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.oc-course-meta span {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  gap: 5px;
}

.oc-cta {
  text-align: center;
  background: rgba(99, 102, 241, 0.1);
  border-radius: var(--radius-lg);
  padding: 40px;
  margin-top: 40px;
  border: 1px solid rgba(99, 102, 241, 0.3);
}

.oc-cta p {
  color: rgba(255, 255, 255, 0.85);
  font-size: 1.05rem;
  margin-bottom: 20px;
}

.oc-cta-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
}

/* ========================================
   适用人群
   ======================================== */
.audience-hero-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
  margin-bottom: 60px;
}

.audience-hero-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 40px 36px;
  border: 2px solid var(--light-2);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.audience-hero-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient);
}

.audience-hero-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.audience-hero-badge {
  display: inline-block;
  background: var(--gradient);
  color: var(--white);
  padding: 5px 14px;
  border-radius: 50px;
  font-size: 0.78rem;
  margin-bottom: 16px;
}

.audience-hero-icon {
  width: 64px;
  height: 64px;
  border-radius: 18px;
  background: var(--gradient);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  margin-bottom: 20px;
}

.audience-hero-card h3 {
  font-size: 1.5rem;
  font-weight: 800;
  margin-bottom: 12px;
  color: var(--dark);
}

.audience-hero-desc {
  color: var(--gray);
  font-size: 0.95rem;
  line-height: 1.8;
  margin-bottom: 20px;
}

.audience-hero-list li {
  padding: 8px 0;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 10px;
  border-bottom: 1px solid var(--light-2);
  color: var(--dark-3);
}

.audience-hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.audience-hero-tags span {
  padding: 5px 14px;
  background: var(--light);
  border-radius: 50px;
  font-size: 0.8rem;
  color: var(--gray);
}

.audience-sub-title {
  text-align: center;
  font-size: 1.3rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 40px;
  color: var(--dark);
}

.audience-sub-title::before,
.audience-sub-title::after {
  content: '';
  flex: 1;
  max-width: 100px;
  height: 2px;
  background: var(--light-2);
}

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

.audience-card {
  background: var(--light);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  transition: var(--transition);
}

.audience-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.audience-icon {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  background: var(--gradient);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin: 0 auto 16px;
}

.audience-card h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--dark);
}

.audience-card p {
  color: var(--gray);
  font-size: 0.85rem;
  line-height: 1.6;
}

/* ========================================
   退款承诺
   ======================================== */
.guarantee {
  background: var(--light);
  padding: 60px 0;
}

.guarantee-banner {
  display: flex;
  align-items: center;
  gap: 28px;
  background: linear-gradient(135deg, #ecfdf5 0%, #d1fae5 100%);
  border: 2px solid var(--success);
  border-radius: var(--radius-lg);
  padding: 36px 40px;
  box-shadow: 0 4px 20px rgba(16, 185, 129, 0.15);
}

.guarantee-icon {
  width: 72px;
  height: 72px;
  min-width: 72px;
  border-radius: 50%;
  background: var(--success);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  color: var(--white);
  box-shadow: 0 4px 15px rgba(16, 185, 129, 0.3);
}

.guarantee-content h3 {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--dark);
  margin-bottom: 8px;
}

.guarantee-content p {
  color: var(--gray);
  font-size: 0.95rem;
  line-height: 1.7;
}

@media (max-width: 768px) {
  .guarantee-banner {
    flex-direction: column;
    text-align: center;
    padding: 28px 24px;
    gap: 16px;
  }

  .guarantee-icon {
    width: 60px;
    height: 60px;
    min-width: 60px;
    font-size: 1.5rem;
  }

  .guarantee-content h3 {
    font-size: 1.2rem;
  }
}

/* ========================================
   联系方式
   ======================================== */
.contact {
  background: linear-gradient(135deg, #0f172a 0%, #1e1b4b 100%);
  color: var(--white);
}

.contact-wrapper {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 60px;
}

.contact-info h2 {
  font-size: 2.2rem;
  font-weight: 900;
  margin-bottom: 24px;
}

.contact-benefits li {
  display: flex;
  align-items: center;
  gap: 10px;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 12px;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 12px;
  color: rgba(255, 255, 255, 0.7);
  margin-bottom: 16px;
}

.contact-item i {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
}

.wechat-card {
  background: rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-lg);
  padding: 40px;
  text-align: center;
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.qr-placeholder {
  width: 200px;
  height: 200px;
  background: var(--white);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto;
}

.contact-form {
  background: rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-lg);
  padding: 32px;
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.form-group {
  margin-bottom: 20px;
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 14px 20px;
  border: 1px solid rgba(255, 255, 255, 0.2);
  background: rgba(255, 255, 255, 0.05);
  color: var(--white);
  border-radius: var(--radius);
  font-size: 0.95rem;
  transition: var(--transition);
}

.form-group input::placeholder {
  color: rgba(255, 255, 255, 0.4);
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.form-group select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='rgba(255,255,255,0.7)' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 16px center;
  background-size: 16px;
  padding-right: 48px;
}

/* ========================================
   内推合作
   ======================================== */
.referral {
  background: var(--white);
}

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

.referral-card {
  padding: 40px 32px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--light-2);
  transition: var(--transition);
}

.referral-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.referral-icon {
  width: 64px;
  height: 64px;
  border-radius: 18px;
  background: var(--gradient);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  margin-bottom: 20px;
}

.referral-card h4 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--dark);
}

.referral-card p {
  color: var(--gray);
  font-size: 0.9rem;
  line-height: 1.7;
}

/* ========================================
   学完即变现板块 (新增)
   ======================================== */
.value-section {
  background: var(--white);
}

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

.value-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 36px 28px;
  text-align: center;
  border: 1px solid var(--light-2);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.value-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--gradient);
}

.value-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-xl);
  border-color: var(--primary-light);
}

.value-icon {
  width: 64px;
  height: 64px;
  border-radius: 18px;
  background: var(--gradient);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  margin: 0 auto 20px;
}

.value-card h4 {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--dark);
}

.value-card p {
  color: var(--gray);
  font-size: 0.9rem;
  line-height: 1.7;
  margin-bottom: 20px;
}

.value-list {
  text-align: left;
}

.value-list li {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 6px 0;
  font-size: 0.85rem;
  color: var(--dark-3);
}

.value-list li i {
  color: var(--success);
  font-size: 0.8rem;
}

.value-highlight {
  background: var(--gradient);
  color: var(--white);
  border-radius: var(--radius-lg);
  padding: 48px;
  margin-top: 48px;
  text-align: center;
}

.value-highlight h3 {
  font-size: 1.5rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.value-highlight p {
  color: rgba(255, 255, 255, 0.85);
  font-size: 1.05rem;
  margin-bottom: 24px;
}

.value-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 60px;
}

.value-stat {
  text-align: center;
}

.value-stat-number {
  font-size: 2.5rem;
  font-weight: 900;
}

.value-stat-label {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
}

/* ========================================
   页脚
   ======================================== */
.footer {
  background: var(--dark);
  color: rgba(255, 255, 255, 0.7);
  padding: 60px 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer h4 {
  color: var(--white);
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 20px;
}

.footer-links li {
  margin-bottom: 12px;
}

.footer-links a {
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--primary-light);
}

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

.social-links a {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.social-links a:hover {
  background: var(--gradient);
}

.footer-bottom {
  text-align: center;
  padding: 24px 0;
  font-size: 0.85rem;
}

/* ========================================
   回到顶部按钮
   ======================================== */
.back-to-top {
  position: fixed;
  bottom: 30px;
  right: 30px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--gradient);
  color: var(--white);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: var(--transition);
  z-index: 999;
  border: none;
  box-shadow: var(--shadow-lg);
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

/* ========================================
   滚动动画
   ======================================== */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ========================================
   响应式设计 - 平板 (1024px)
   ======================================== */
@media (max-width: 1024px) {
  .hero-title {
    font-size: 2.8rem;
  }

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

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

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

  .level-intermediate {
    transform: none;
  }

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

  .audience-hero-grid {
    grid-template-columns: 1fr;
  }

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

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

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

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

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

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

/* ========================================
   响应式设计 - 手机 (768px)
   ======================================== */
@media (max-width: 768px) {
  .navbar {
    padding: 8px 0;
  }

  .nav-container {
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px;
  }

  .navbar.scrolled {
    background: rgba(15, 23, 42, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
  }

  .nav-links {
    width: 100%;
    justify-content: center;
    flex-wrap: wrap;
    gap: 4px;
    order: 3;
    padding-top: 6px;
  }

  .nav-links a {
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 0.78rem;
    background: rgba(255, 255, 255, 0.08);
  }

  .nav-links a.nav-highlight {
    padding: 6px 14px;
    font-size: 0.78rem;
  }

  .nav-hide-mobile {
    display: none !important;
  }

  .nav-full {
    display: none;
  }

  .nav-short {
    display: inline;
  }

  .hamburger {
    display: none;
  }

  .hero {
    padding: 100px 24px 60px;
  }

  .hero-title {
    font-size: 2rem;
  }

  .section {
    padding: 60px 0;
  }

  .section-title {
    font-size: 1.8rem;
  }

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

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

  .learning-modes {
    grid-template-columns: 1fr;
  }

  .audience-hero-card {
    padding: 28px 20px;
  }

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

  .contact-info h2 {
    font-size: 1.6rem;
  }

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

  .anxiety {
    display: none;
  }

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

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

  .value-card {
    padding: 28px 20px;
  }

  .value-highlight {
    padding: 32px 20px;
  }

  .value-stats {
    flex-wrap: wrap;
    gap: 24px;
  }

  .crisis-stats {
    flex-wrap: wrap;
    gap: 24px;
  }

  .oc-capabilities {
    grid-template-columns: 1fr;
  }

  .oc-course-content {
    grid-template-columns: 1fr;
  }

  .schedule-table-wrapper {
    -webkit-overflow-scrolling: touch;
  }

  table {
    min-width: 600px;
  }
}

/* ========================================
   响应式设计 - 小屏手机 (480px)
   ======================================== */
@media (max-width: 480px) {
  .hero-title {
    font-size: 1.6rem;
  }

  .hero-actions {
    flex-direction: column;
    align-items: center;
  }

  .btn-lg {
    width: 100%;
    justify-content: center;
  }

  .hero-stats {
    flex-direction: column;
    gap: 16px;
  }

  .course-filters {
    gap: 6px;
  }

  .filter-btn {
    padding: 8px 16px;
    font-size: 0.8rem;
  }

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

  .value-card h4 {
    font-size: 1.1rem;
  }

  .value-card p {
    font-size: 0.88rem;
  }

  .value-list li {
    font-size: 0.85rem;
  }
}