/* ==========================================
   17C视频社区 - 主样式文件
   ========================================== */

/* 基础重置与变量 */
:root {
  --primary: #e8230a;
  --primary-dark: #c41a07;
  --primary-light: #ff4d33;
  --secondary: #ff6b35;
  --accent: #ffd700;
  --dark: #1a1a2e;
  --dark-2: #16213e;
  --dark-3: #0f3460;
  --text-main: #222222;
  --text-sub: #555555;
  --text-light: #888888;
  --bg-light: #f8f9fa;
  --bg-white: #ffffff;
  --border: #e5e7eb;
  --shadow: 0 4px 20px rgba(0,0,0,0.08);
  --shadow-hover: 0 8px 30px rgba(232,35,10,0.15);
  --radius: 12px;
  --radius-sm: 8px;
  --radius-lg: 20px;
  --transition: all 0.3s ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  color: var(--text-main);
  background: var(--bg-white);
  line-height: 1.7;
  font-size: 15px;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

ul, ol {
  list-style: none;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.section {
  padding: 80px 0;
}

.section-alt {
  background: var(--bg-light);
}

/* ==================== 标题样式 ==================== */
.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-tag {
  display: inline-block;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  font-size: 12px;
  font-weight: 600;
  padding: 4px 14px;
  border-radius: 20px;
  letter-spacing: 1px;
  margin-bottom: 16px;
  text-transform: uppercase;
}

.section-title {
  font-size: 2rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 16px;
  line-height: 1.3;
}

.section-title span {
  color: var(--primary);
}

.section-desc {
  font-size: 1rem;
  color: var(--text-sub);
  max-width: 600px;
  margin: 0 auto;
}

/* ==================== 按钮样式 ==================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: 50px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: var(--transition);
  text-decoration: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
  box-shadow: 0 4px 15px rgba(232,35,10,0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(232,35,10,0.4);
  color: #fff;
}

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

.btn-outline:hover {
  background: var(--primary);
  color: #fff;
  transform: translateY(-2px);
}

.btn-white {
  background: #fff;
  color: var(--primary);
  box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.btn-white:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

/* ==================== 顶部导航 ==================== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(255,255,255,0.97);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  transition: var(--transition);
}

.header.scrolled {
  box-shadow: 0 2px 20px rgba(0,0,0,0.1);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.6rem;
  font-weight: 900;
  color: var(--primary);
  letter-spacing: -1px;
}

.logo-icon {
  width: 42px;
  height: 42px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 1.2rem;
  font-weight: 900;
}

.logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.logo-name {
  font-size: 1.4rem;
  font-weight: 900;
  color: var(--primary);
}

.logo-sub {
  font-size: 0.65rem;
  color: var(--text-light);
  font-weight: 400;
  letter-spacing: 1px;
}

.nav {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav a {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-main);
  position: relative;
  padding-bottom: 4px;
}

.nav a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: var(--transition);
}

.nav a:hover::after,
.nav a.active::after {
  width: 100%;
}

.nav a:hover,
.nav a.active {
  color: var(--primary);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.mobile-menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 5px;
}

.mobile-menu-btn span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-main);
  border-radius: 2px;
  transition: var(--transition);
}

/* ==================== 搜索框 ==================== */
.search-bar {
  background: var(--bg-light);
  border-bottom: 1px solid var(--border);
  padding: 12px 0;
}

.search-inner {
  display: flex;
  align-items: center;
  gap: 12px;
  max-width: 700px;
  margin: 0 auto;
  padding: 0 20px;
}

.search-wrap {
  flex: 1;
  position: relative;
}

.search-wrap input {
  width: 100%;
  padding: 10px 20px 10px 44px;
  border: 2px solid var(--border);
  border-radius: 50px;
  font-size: 14px;
  background: #fff;
  transition: var(--transition);
  outline: none;
  font-family: inherit;
}

.search-wrap input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(232,35,10,0.1);
}

.search-wrap .search-icon {
  position: absolute;
  left: 16px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-light);
  font-size: 16px;
}

.search-btn {
  padding: 10px 24px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 50px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
  font-family: inherit;
}

.search-btn:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
}

/* ==================== 首屏Hero ==================== */
.hero {
  padding-top: 130px;
  padding-bottom: 80px;
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
  position: relative;
  overflow: hidden;
  min-height: 600px;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(232,35,10,0.15) 0%, transparent 70%);
  border-radius: 50%;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(255,107,53,0.1) 0%, transparent 70%);
  border-radius: 50%;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(232,35,10,0.15);
  border: 1px solid rgba(232,35,10,0.3);
  color: #ff8070;
  padding: 6px 16px;
  border-radius: 50px;
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 24px;
}

.hero-badge::before {
  content: '●';
  color: var(--primary);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

.hero h1 {
  font-size: 3rem;
  font-weight: 900;
  color: #fff;
  line-height: 1.2;
  margin-bottom: 20px;
}

.hero h1 .highlight {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 1.05rem;
  color: rgba(255,255,255,0.75);
  margin-bottom: 32px;
  line-height: 1.8;
}

.hero-stats {
  display: flex;
  gap: 32px;
  margin-bottom: 36px;
}

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

.hero-stat .num {
  display: block;
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
}

.hero-stat .label {
  font-size: 12px;
  color: rgba(255,255,255,0.6);
  margin-top: 4px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-img-wrap {
  position: relative;
}

.hero-img-wrap img {
  border-radius: var(--radius-lg);
  box-shadow: 0 20px 60px rgba(0,0,0,0.4);
  width: 100%;
}

.hero-float-card {
  position: absolute;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(10px);
  border-radius: var(--radius);
  padding: 12px 18px;
  box-shadow: 0 8px 30px rgba(0,0,0,0.2);
  display: flex;
  align-items: center;
  gap: 10px;
}

.hero-float-card.card-1 {
  bottom: -20px;
  left: -20px;
}

.hero-float-card.card-2 {
  top: -15px;
  right: -15px;
}

.hero-float-card .card-icon {
  font-size: 1.5rem;
}

.hero-float-card .card-text strong {
  display: block;
  font-size: 14px;
  font-weight: 700;
  color: var(--dark);
}

.hero-float-card .card-text span {
  font-size: 12px;
  color: var(--text-light);
}

/* ==================== 视频卡片 ==================== */
.video-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.video-card {
  background: #fff;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: var(--transition);
  cursor: pointer;
}

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

.video-thumb {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16/9;
}

.video-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.video-card:hover .video-thumb img {
  transform: scale(1.05);
}

.video-play-btn {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0);
  transition: var(--transition);
}

.video-card:hover .video-play-btn {
  background: rgba(0,0,0,0.35);
}

.play-icon {
  width: 56px;
  height: 56px;
  background: rgba(255,255,255,0.95);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: scale(0.7);
  transition: var(--transition);
  box-shadow: 0 4px 20px rgba(0,0,0,0.3);
}

.video-card:hover .play-icon {
  opacity: 1;
  transform: scale(1);
}

.play-icon::after {
  content: '';
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 10px 0 10px 18px;
  border-color: transparent transparent transparent var(--primary);
  margin-left: 4px;
}

.video-tag {
  position: absolute;
  top: 12px;
  left: 12px;
  background: var(--primary);
  color: #fff;
  font-size: 11px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 20px;
}

.video-duration {
  position: absolute;
  bottom: 10px;
  right: 10px;
  background: rgba(0,0,0,0.7);
  color: #fff;
  font-size: 12px;
  padding: 2px 8px;
  border-radius: 4px;
}

.video-info {
  padding: 16px;
}

.video-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--dark);
  margin-bottom: 8px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.video-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  color: var(--text-light);
}

.video-stats {
  display: flex;
  gap: 12px;
}

.video-stats span {
  display: flex;
  align-items: center;
  gap: 4px;
}

/* ==================== 功能特性 ==================== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.feature-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 32px 28px;
  box-shadow: var(--shadow);
  transition: var(--transition);
  border: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  transform: scaleX(0);
  transition: var(--transition);
}

.feature-card:hover::before {
  transform: scaleX(1);
}

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

.feature-icon {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.feature-tag {
  display: inline-block;
  background: rgba(232,35,10,0.08);
  color: var(--primary);
  font-size: 11px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 20px;
  margin-bottom: 12px;
}

.feature-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 10px;
}

.feature-card p {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.7;
}

/* ==================== 场景应用 ==================== */
.scenarios-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}

.scenario-card {
  border-radius: var(--radius);
  overflow: hidden;
  position: relative;
  aspect-ratio: 16/9;
  cursor: pointer;
}

.scenario-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.scenario-card:hover img {
  transform: scale(1.05);
}

.scenario-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(0,0,0,0.75) 0%, transparent 60%);
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 24px;
}

.scenario-tag {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  font-size: 11px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 20px;
  margin-bottom: 8px;
  align-self: flex-start;
}

.scenario-overlay h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 6px;
}

.scenario-overlay p {
  font-size: 13px;
  color: rgba(255,255,255,0.8);
}

/* ==================== 教程步骤 ==================== */
.tutorial-steps {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 20px;
  position: relative;
}

.tutorial-steps::before {
  content: '';
  position: absolute;
  top: 40px;
  left: 10%;
  right: 10%;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  z-index: 0;
}

.tutorial-step {
  text-align: center;
  position: relative;
  z-index: 1;
}

.step-icon {
  width: 80px;
  height: 80px;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  margin: 0 auto 16px;
  box-shadow: 0 4px 20px rgba(232,35,10,0.3);
  border: 4px solid #fff;
}

.step-num {
  display: block;
  font-size: 11px;
  font-weight: 700;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 1px;
  margin-bottom: 6px;
}

.tutorial-step h3 {
  font-size: 14px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 6px;
}

.tutorial-step p {
  font-size: 12px;
  color: var(--text-sub);
  line-height: 1.6;
}

.step-duration {
  display: inline-block;
  background: var(--bg-light);
  color: var(--text-light);
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 10px;
  margin-top: 6px;
}

/* ==================== 更新日志 ==================== */
.changelog-list {
  max-width: 800px;
  margin: 0 auto;
}

.changelog-item {
  display: flex;
  gap: 24px;
  margin-bottom: 40px;
  position: relative;
}

.changelog-item:not(:last-child)::after {
  content: '';
  position: absolute;
  left: 60px;
  top: 80px;
  bottom: -40px;
  width: 2px;
  background: var(--border);
}

.changelog-version {
  flex-shrink: 0;
  text-align: center;
  width: 80px;
}

.version-badge {
  display: inline-block;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  font-size: 12px;
  font-weight: 700;
  margin-bottom: 6px;
}

.version-badge.major {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: #fff;
}

.version-badge.minor {
  background: #3b82f6;
  color: #fff;
}

.version-badge.patch {
  background: #10b981;
  color: #fff;
}

.version-date {
  font-size: 11px;
  color: var(--text-light);
}

.changelog-content {
  flex: 1;
  background: #fff;
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.changelog-content h3 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 14px;
}

.changelog-content ul {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.changelog-content li {
  font-size: 14px;
  color: var(--text-sub);
  padding-left: 20px;
  position: relative;
}

.changelog-content li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: 700;
}

/* ==================== FAQ ==================== */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.faq-item {
  background: #fff;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  overflow: hidden;
  transition: var(--transition);
}

.faq-item:hover {
  border-color: var(--primary);
  box-shadow: var(--shadow-hover);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  cursor: pointer;
  font-size: 15px;
  font-weight: 600;
  color: var(--dark);
  gap: 16px;
}

.faq-question::after {
  content: '+';
  font-size: 1.5rem;
  color: var(--primary);
  flex-shrink: 0;
  transition: var(--transition);
  line-height: 1;
}

.faq-item.open .faq-question::after {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease;
}

.faq-item.open .faq-answer {
  max-height: 300px;
}

.faq-answer p {
  padding: 0 24px 20px;
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.8;
  border-top: 1px solid var(--border);
  padding-top: 16px;
}

/* ==================== 用户评价 ==================== */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.review-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  transition: var(--transition);
  position: relative;
}

.review-card::before {
  content: '"';
  position: absolute;
  top: 16px;
  right: 24px;
  font-size: 4rem;
  color: rgba(232,35,10,0.08);
  font-family: Georgia, serif;
  line-height: 1;
}

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

.review-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
}

.review-avatar {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--border);
}

.review-info strong {
  display: block;
  font-size: 15px;
  font-weight: 700;
  color: var(--dark);
}

.review-info span {
  font-size: 12px;
  color: var(--text-light);
}

.review-stars {
  color: var(--accent);
  font-size: 14px;
  margin-bottom: 12px;
}

.review-content {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.8;
  margin-bottom: 14px;
}

.review-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  color: var(--text-light);
}

.review-tag {
  background: rgba(232,35,10,0.08);
  color: var(--primary);
  padding: 2px 8px;
  border-radius: 10px;
  font-size: 11px;
  font-weight: 600;
}

/* ==================== 联系我们 ==================== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: start;
}

.contact-info h2 {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 16px;
}

.contact-info p {
  color: var(--text-sub);
  margin-bottom: 32px;
  line-height: 1.8;
}

.contact-items {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.contact-item-icon {
  width: 48px;
  height: 48px;
  background: rgba(232,35,10,0.08);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  flex-shrink: 0;
}

.contact-item-text strong {
  display: block;
  font-size: 14px;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 4px;
}

.contact-item-text span {
  font-size: 13px;
  color: var(--text-sub);
}

.contact-form {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 40px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
}

.contact-form h3 {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--dark);
  margin-bottom: 24px;
}

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

.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 8px;
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 12px 16px;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-family: inherit;
  transition: var(--transition);
  outline: none;
  background: var(--bg-light);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  border-color: var(--primary);
  background: #fff;
  box-shadow: 0 0 0 3px rgba(232,35,10,0.1);
}

.form-group textarea {
  resize: vertical;
  min-height: 120px;
}

/* ==================== 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;
  margin-bottom: 40px;
}

.footer-brand .logo {
  margin-bottom: 16px;
}

.footer-brand .logo-name {
  color: #fff;
}

.footer-brand p {
  font-size: 14px;
  line-height: 1.8;
  margin-bottom: 20px;
}

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

.social-btn {
  width: 38px;
  height: 38px;
  background: rgba(255,255,255,0.1);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  transition: var(--transition);
  cursor: pointer;
}

.social-btn:hover {
  background: var(--primary);
  transform: translateY(-2px);
}

.footer-col h4 {
  font-size: 14px;
  font-weight: 700;
  color: #fff;
  margin-bottom: 16px;
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-col li a {
  font-size: 13px;
  color: rgba(255,255,255,0.6);
  transition: var(--transition);
}

.footer-col li a:hover {
  color: var(--primary);
  padding-left: 4px;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 20px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-bottom p {
  font-size: 13px;
}

.footer-bottom a {
  color: rgba(255,255,255,0.5);
}

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

.footer-links {
  display: flex;
  gap: 20px;
}

.footer-links a {
  font-size: 13px;
  color: rgba(255,255,255,0.5);
}

/* ==================== 统计数字 ==================== */
.stats-section {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  padding: 60px 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 40px;
  text-align: center;
}

.stat-item .num {
  font-size: 2.5rem;
  font-weight: 900;
  color: #fff;
  display: block;
  line-height: 1;
  margin-bottom: 8px;
}

.stat-item .label {
  font-size: 14px;
  color: rgba(255,255,255,0.85);
}

/* ==================== 面包屑 ==================== */
.breadcrumb {
  padding: 16px 0;
  background: var(--bg-light);
  border-bottom: 1px solid var(--border);
}

.breadcrumb-inner {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-light);
}

.breadcrumb-inner a {
  color: var(--primary);
}

.breadcrumb-inner a:hover {
  text-decoration: underline;
}

.breadcrumb-inner span {
  color: var(--text-light);
}

/* ==================== 内页Hero ==================== */
.page-hero {
  background: linear-gradient(135deg, var(--dark) 0%, var(--dark-3) 100%);
  padding: 120px 0 60px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.page-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at center, rgba(232,35,10,0.1) 0%, transparent 70%);
}

.page-hero h1 {
  font-size: 2.5rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 16px;
  position: relative;
}

.page-hero p {
  font-size: 1.05rem;
  color: rgba(255,255,255,0.75);
  max-width: 600px;
  margin: 0 auto;
  position: relative;
}

/* ==================== 响应式 ==================== */
@media (max-width: 1024px) {
  .hero-inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .hero-img-wrap {
    display: none;
  }
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .tutorial-steps {
    grid-template-columns: repeat(3, 1fr);
  }
  .tutorial-steps::before {
    display: none;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav, .header-actions .btn {
    display: none;
  }
  .mobile-menu-btn {
    display: flex;
  }
  .hero h1 {
    font-size: 2rem;
  }
  .section {
    padding: 60px 0;
  }
  .section-title {
    font-size: 1.6rem;
  }
  .video-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .features-grid {
    grid-template-columns: 1fr;
  }
  .scenarios-grid {
    grid-template-columns: 1fr;
  }
  .tutorial-steps {
    grid-template-columns: 1fr;
  }
  .reviews-grid {
    grid-template-columns: 1fr;
  }
  .contact-grid {
    grid-template-columns: 1fr;
  }
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .video-grid {
    grid-template-columns: 1fr;
  }
  .hero-stats {
    gap: 20px;
  }
  .hero-stat .num {
    font-size: 1.4rem;
  }
  .contact-form {
    padding: 24px;
  }
}

/* ==================== 工具类 ==================== */
.text-center { text-align: center; }
.text-primary { color: var(--primary); }
.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mb-8 { margin-bottom: 8px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }

/* 移动端菜单 */
.mobile-nav {
  display: none;
  position: fixed;
  top: 70px;
  left: 0;
  right: 0;
  background: #fff;
  border-bottom: 1px solid var(--border);
  padding: 20px;
  z-index: 999;
  box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.mobile-nav.open {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.mobile-nav a {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-main);
  padding: 8px 0;
  border-bottom: 1px solid var(--border);
}

.mobile-nav a:hover {
  color: var(--primary);
}

/* 加载动画 */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-in {
  animation: fadeInUp 0.6s ease forwards;
}