/* ============================
   AI 创造力课程 — 样式表
   ============================ */

:root {
  --primary: #1A3A5C;
  --primary-light: #2A5A8C;
  --accent: #F5A623;
  --accent-hover: #E09510;
  --bg-white: #FFFFFF;
  --bg-light: #F7F8FA;
  --bg-dark: #1A3A5C;
  --text-dark: #2C2C2C;
  --text-muted: #6B7280;
  --text-on-dark: #FFFFFF;
  --border: #E5E7EB;
  --success: #10B981;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 70px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC",
               sans-serif;
  font-size: 16px;
  line-height: 1.8;
  color: var(--text-dark);
  background: var(--bg-white);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
img, svg { display: block; max-width: 100%; }

/* ---------- 容器 ---------- */
.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}
.container-narrow {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- 通用版块 ---------- */
.section {
  padding: 80px 0;
}
.section-white { background: var(--bg-white); }
.section-light { background: var(--bg-light); }

.section-header {
  text-align: center;
  margin-bottom: 56px;
}
.section-title {
  font-size: 30px;
  font-weight: 700;
  color: var(--primary);
  line-height: 1.4;
  margin-bottom: 14px;
}
.section-subtitle {
  font-size: 16px;
  color: var(--text-muted);
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-block;
  padding: 14px 32px;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 600;
  transition: all 0.25s ease;
  cursor: pointer;
}
.btn-accent {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 4px 14px rgba(245, 166, 35, 0.35);
}
.btn-accent:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(245, 166, 35, 0.45);
}

/* ---------- 导航栏 ---------- */
.navbar {
  position: sticky;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.04);
}
.nav-container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.nav-logo {
  font-size: 17px;
  font-weight: 700;
  color: var(--primary);
  letter-spacing: 0.5px;
}
.nav-links {
  display: flex;
  gap: 32px;
}
.nav-links a {
  font-size: 15px;
  color: var(--text-dark);
  transition: color 0.2s ease;
  position: relative;
}
.nav-links a:hover {
  color: var(--primary-light);
}
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 26px;
  height: 20px;
  padding: 0;
}
.nav-toggle span {
  display: block;
  height: 2px;
  background: var(--primary);
  border-radius: 2px;
  transition: all 0.3s ease;
}
.nav-toggle.active span:nth-child(1) { transform: translateY(9px) rotate(45deg); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: translateY(-9px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  background: linear-gradient(135deg, #1A3A5C 0%, #234775 100%);
  color: var(--text-on-dark);
  padding: 96px 0 104px;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: "";
  position: absolute;
  top: -120px; right: -120px;
  width: 360px; height: 360px;
  background: radial-gradient(circle, rgba(245,166,35,0.18) 0%, transparent 70%);
  border-radius: 50%;
}
.hero::after {
  content: "";
  position: absolute;
  bottom: -100px; left: -100px;
  width: 320px; height: 320px;
  background: radial-gradient(circle, rgba(42,90,140,0.4) 0%, transparent 70%);
  border-radius: 50%;
}
.hero-inner {
  position: relative;
  text-align: center;
  z-index: 1;
}
.hero-eyebrow {
  font-size: 14px;
  letter-spacing: 1.5px;
  color: rgba(255, 255, 255, 0.75);
  margin-bottom: 20px;
}
.hero-title {
  font-size: 46px;
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 22px;
  color: #fff;
}
.hero-subtitle {
  font-size: 17px;
  color: rgba(255, 255, 255, 0.82);
  line-height: 1.8;
  max-width: 640px;
  margin: 0 auto 36px;
}
.hero-network {
  width: 320px;
  height: auto;
  margin: 0 auto 36px;
  opacity: 0.9;
}
.hero-cta {
  display: inline-block;
}

/* ---------- 课程大纲 ---------- */
.curriculum-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
}
.stage-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0;
  overflow: hidden;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  display: flex;
  flex-direction: column;
  cursor: pointer;
}
.stage-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
}
.stage-stripe {
  height: 4px;
  background: var(--stage-color);
}
.stage-badge {
  display: inline-block;
  margin: 20px 20px 12px;
  padding: 4px 12px;
  background: rgba(0, 0, 0, 0.04);
  color: var(--primary);
  font-size: 13px;
  font-weight: 600;
  border-radius: 20px;
  align-self: flex-start;
}
.stage-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--primary);
  padding: 0 20px;
  margin-bottom: 6px;
  line-height: 1.5;
}
.stage-meta {
  font-size: 13px;
  color: var(--text-muted);
  padding: 0 20px;
  margin-bottom: 14px;
}
.stage-output {
  font-size: 14px;
  color: var(--accent);
  font-weight: 600;
  padding: 12px 20px;
  margin: 0 20px 14px;
  background: rgba(245, 166, 35, 0.08);
  border-radius: 8px;
  line-height: 1.5;
}
.stage-desc {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
  padding: 0 20px 16px;
  flex-grow: 1;
}
.stage-cta {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--primary);
  padding: 0 20px 22px;
  transition: color 0.25s ease, transform 0.25s ease;
}
.stage-card:hover .stage-cta {
  color: var(--accent);
  transform: translateX(3px);
}

/* ---------- 课程详情 Modal ---------- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.55);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
  overflow-y: auto;
}
.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}
.modal-content {
  background: var(--bg-white);
  border-radius: 16px;
  width: 100%;
  max-width: 720px;
  max-height: 85vh;
  overflow-y: auto;
  position: relative;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.3);
  transform: translateY(20px);
  opacity: 0;
  transition: transform 0.3s ease, opacity 0.3s ease;
  -webkit-overflow-scrolling: touch;
}
.modal-overlay.active .modal-content {
  transform: translateY(0);
  opacity: 1;
}
.modal-close {
  position: absolute;
  top: 14px;
  right: 14px;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.92);
  color: var(--text-dark);
  font-size: 24px;
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 5;
  transition: background 0.2s ease, transform 0.2s ease;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}
.modal-close:hover {
  background: #fff;
  transform: rotate(90deg);
}
.modal-hero {
  height: 240px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 1px;
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.25);
  border-radius: 16px 16px 0 0;
  padding: 0 24px;
  text-align: center;
}
.modal-hero-1 { background: linear-gradient(135deg, #3B82F6 0%, #06B6D4 100%); }
.modal-hero-2 { background: linear-gradient(135deg, #10B981 0%, #34D399 100%); }
.modal-hero-3 { background: linear-gradient(135deg, #8B5CF6 0%, #EC4899 100%); }
.modal-hero-4 { background: linear-gradient(135deg, #F59E0B 0%, #F97316 100%); }
.modal-hero-5 { background: linear-gradient(135deg, #EF4444 0%, #F97316 100%); }
.modal-body {
  padding: 28px 36px 36px;
}
.modal-badge {
  display: inline-block;
  background: rgba(26, 58, 92, 0.08);
  color: var(--primary);
  font-size: 13px;
  font-weight: 600;
  padding: 4px 14px;
  border-radius: 20px;
  margin-bottom: 14px;
}
.modal-title {
  font-size: 26px;
  font-weight: 700;
  color: var(--primary);
  line-height: 1.4;
  margin-bottom: 8px;
}
.modal-meta {
  font-size: 14px;
  color: var(--text-muted);
}
.modal-divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 22px 0;
}
.modal-section {
  margin-bottom: 26px;
}
.modal-section:last-child {
  margin-bottom: 0;
}
.modal-section-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 12px;
}
.modal-section-content p,
.modal-section p {
  font-size: 15px;
  color: var(--text-dark);
  line-height: 1.85;
  margin-bottom: 12px;
}
.modal-section-content p:last-child,
.modal-section p:last-child {
  margin-bottom: 0;
}
.modal-list {
  list-style: none;
  padding: 0;
}
.modal-list li {
  position: relative;
  padding: 8px 0 8px 22px;
  font-size: 15px;
  color: var(--text-dark);
  line-height: 1.75;
  border-bottom: 1px dashed var(--border);
}
.modal-list li:last-child {
  border-bottom: none;
}
.modal-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 18px;
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 50%;
}
.modal-list li strong {
  color: var(--primary);
  font-weight: 700;
}
.modal-notice {
  background: rgba(245, 166, 35, 0.08);
  border-left: 4px solid var(--accent);
  border-radius: 8px;
  padding: 18px 20px;
}
.modal-notice .modal-section-title {
  margin-bottom: 8px;
}
.modal-notice p {
  font-size: 14px;
  color: var(--text-dark);
  line-height: 1.8;
}

body.modal-open {
  overflow: hidden;
}

/* ---------- 教学特色 ---------- */
.features-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}
.feature-card {
  background: var(--bg-white);
  border-radius: 12px;
  padding: 32px 28px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.05);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  display: flex;
  align-items: flex-start;
  gap: 20px;
}
.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.1);
}
.feature-icon {
  flex-shrink: 0;
  width: 56px;
  height: 56px;
  background: rgba(26, 58, 92, 0.06);
  color: var(--primary);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.feature-icon svg {
  width: 32px;
  height: 32px;
}
.feature-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 8px;
  line-height: 1.5;
}
.feature-desc {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.75;
}

/* ---------- 学生作品展厅 ---------- */
.works-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.work-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.work-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
}
.work-image {
  height: 200px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 1px;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}
.work-image-1 {
  background: linear-gradient(135deg, #4FACFE 0%, #00C6A2 100%);
}
.work-image-2 {
  background: linear-gradient(135deg, #A78BFA 0%, #F472B6 100%);
}
.work-image-3 {
  background: linear-gradient(135deg, #FB923C 0%, #EF4444 100%);
}
.work-body {
  padding: 22px 24px 26px;
}
.work-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 10px;
}
.work-desc {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 14px;
}
.work-tag {
  display: inline-block;
  font-size: 12px;
  color: var(--primary-light);
  background: rgba(42, 90, 140, 0.08);
  padding: 4px 12px;
  border-radius: 20px;
}

/* ---------- FAQ ---------- */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.faq-item {
  background: var(--bg-white);
  border-radius: 12px;
  border: 1px solid var(--border);
  overflow: hidden;
  transition: box-shadow 0.25s ease;
}
.faq-item.open {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
}
.faq-question {
  width: 100%;
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 16px;
  font-weight: 600;
  color: var(--primary);
  text-align: left;
  line-height: 1.6;
}
.faq-question:hover {
  background: rgba(0, 0, 0, 0.02);
}
.faq-icon {
  flex-shrink: 0;
  width: 16px;
  height: 16px;
  margin-left: 16px;
  position: relative;
  transition: transform 0.3s ease;
}
.faq-icon::before,
.faq-icon::after {
  content: "";
  position: absolute;
  background: var(--primary);
  border-radius: 2px;
}
.faq-icon::before {
  top: 50%; left: 0; right: 0;
  height: 2px;
  transform: translateY(-50%);
}
.faq-icon::after {
  top: 0; bottom: 0; left: 50%;
  width: 2px;
  transform: translateX(-50%);
  transition: transform 0.3s ease;
}
.faq-item.open .faq-icon::after {
  transform: translateX(-50%) scaleY(0);
}
.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease;
}
.faq-answer p {
  padding: 0 24px 22px;
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.85;
}

/* ---------- 联系我们 ---------- */
.contact {
  background: linear-gradient(135deg, #1A3A5C 0%, #2A5A8C 100%);
  color: var(--text-on-dark);
  padding: 80px 0 32px;
  position: relative;
  overflow: hidden;
}
.contact-inner {
  text-align: center;
  position: relative;
  z-index: 1;
}
.contact-title {
  font-size: 30px;
  font-weight: 700;
  margin-bottom: 12px;
}
.contact-subtitle {
  font-size: 16px;
  color: rgba(255, 255, 255, 0.8);
  margin-bottom: 48px;
}
.contact-grid {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 64px;
  flex-wrap: wrap;
  margin-bottom: 56px;
}
.contact-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}
.qr-placeholder {
  width: 150px;
  height: 150px;
  background: #fff;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 14px;
  font-weight: 500;
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.2);
}
.contact-label {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.85);
}
.contact-info {
  text-align: left;
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.info-row {
  display: flex;
  align-items: center;
  gap: 14px;
  font-size: 16px;
}
.info-label {
  display: inline-block;
  background: rgba(245, 166, 35, 0.18);
  color: var(--accent);
  padding: 4px 12px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
  min-width: 52px;
  text-align: center;
}
.info-value {
  color: rgba(255, 255, 255, 0.92);
}
.copyright {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.55);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 24px;
}

/* ---------- 滚动渐入动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ============================
   响应式 — 移动端
   ============================ */
@media (max-width: 768px) {
  .section {
    padding: 48px 0;
  }
  .section-title {
    font-size: 22px;
  }
  .section-subtitle {
    font-size: 14px;
  }
  .section-header {
    margin-bottom: 36px;
  }

  /* 导航 */
  .nav-toggle { display: flex; }
  .nav-links {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    flex-direction: column;
    gap: 0;
    padding: 8px 0 16px;
    transform: translateY(-150%);
    transition: transform 0.3s ease;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
  }
  .nav-links.open {
    transform: translateY(0);
  }
  .nav-links a {
    padding: 14px 24px;
    border-bottom: 1px solid var(--border);
  }
  .nav-links a:last-child { border-bottom: none; }

  /* Hero */
  .hero {
    padding: 64px 0 72px;
  }
  .hero-title {
    font-size: 30px;
  }
  .hero-subtitle {
    font-size: 15px;
  }
  .hero-network {
    width: 240px;
  }
  .hero-cta {
    display: block;
    width: 100%;
    box-sizing: border-box;
  }
  .hero-eyebrow {
    font-size: 12px;
  }

  /* 课程 */
  .curriculum-grid {
    grid-template-columns: 1fr;
  }

  /* 特色 */
  .features-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  .feature-card {
    padding: 24px 20px;
    gap: 16px;
  }
  .feature-icon {
    width: 48px;
    height: 48px;
  }
  .feature-icon svg {
    width: 28px;
    height: 28px;
  }

  /* 作品 */
  .works-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }
  .work-image {
    height: 160px;
    font-size: 20px;
  }

  /* FAQ */
  .faq-question {
    font-size: 15px;
    padding: 18px 20px;
  }
  .faq-answer p {
    padding: 0 20px 20px;
    font-size: 14px;
  }

  /* Modal 移动端 */
  .modal-overlay {
    padding: 0;
    align-items: stretch;
  }
  .modal-content {
    max-width: 100%;
    max-height: 100vh;
    height: 100vh;
    border-radius: 0;
  }
  .modal-hero {
    height: 180px;
    font-size: 18px;
    border-radius: 0;
  }
  .modal-body {
    padding: 24px 20px 40px;
  }
  .modal-title {
    font-size: 22px;
  }
  .modal-section-title {
    font-size: 16px;
  }
  .modal-section-content p,
  .modal-section p,
  .modal-list li {
    font-size: 14px;
  }
  .modal-close {
    position: fixed;
    top: 12px;
    right: 12px;
  }

  /* 联系 */
  .contact {
    padding: 56px 0 28px;
  }
  .contact-title {
    font-size: 22px;
  }
  .contact-grid {
    flex-direction: column;
    gap: 36px;
    margin-bottom: 40px;
  }
  .contact-info {
    align-items: center;
    text-align: center;
  }
  .info-row {
    flex-direction: row;
    font-size: 15px;
  }
}

/* 极小屏微调 */
@media (max-width: 380px) {
  .hero-title { font-size: 26px; }
  .nav-logo { font-size: 15px; }
  .container, .container-narrow, .nav-container { padding: 0 18px; }
}