/* 草莓视频汽车改装与视频社区 - 全局样式表 */
/* 设计理念：高端汽车品牌感 + 现代视频社区活力 */

:root {
  /* 品牌色系：深黑 + 赛车红 + 银灰 + 霓虹蓝 */
  --primary-black: #0a0a0a;
  --primary-red: #d32f2f;
  --accent-silver: #c0c0c0;
  --accent-blue: #1e88e5;
  --accent-neon-purple: #9c27b0;
  --text-light: #f5f5f5;
  --text-dark: #1a1a1a;
  --bg-dark: #121212;
  --bg-darker: #0a0a0a;
  --border-color: #2a2a2a;
  --hover-overlay: rgba(211, 47, 47, 0.15);
  
  /* 字体 */
  --font-display: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
  
  /* 间距 */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 4rem;
  
  /* 圆角 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  
  /* 阴影 */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
  --shadow-xl: 0 12px 48px rgba(0, 0, 0, 0.6);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  background-color: var(--bg-dark);
  color: var(--text-light);
  line-height: 1.6;
  font-size: 16px;
}

/* 排版 */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
}

h1 {
  font-size: 3.5rem;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 2.5rem;
  letter-spacing: -0.01em;
}

h3 {
  font-size: 1.875rem;
}

h4 {
  font-size: 1.5rem;
}

h5 {
  font-size: 1.25rem;
}

h6 {
  font-size: 1rem;
}

p {
  margin-bottom: var(--spacing-md);
  font-size: 1rem;
  color: rgba(245, 245, 245, 0.85);
}

a {
  color: var(--accent-blue);
  text-decoration: none;
  transition: color 0.3s ease;
}

a:hover {
  color: var(--primary-red);
}

/* 容器 */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

@media (max-width: 768px) {
  .container {
    padding: 0 var(--spacing-md);
  }
}

/* 按钮 */
.btn {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-lg);
  border: 2px solid transparent;
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  text-align: center;
  font-family: var(--font-display);
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-red), #ff5252);
  color: white;
  box-shadow: var(--shadow-md);
}

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

.btn-secondary {
  background: transparent;
  color: var(--accent-blue);
  border-color: var(--accent-blue);
}

.btn-secondary:hover {
  background: var(--accent-blue);
  color: white;
}

.btn-outline {
  background: transparent;
  color: var(--text-light);
  border-color: var(--text-light);
}

.btn-outline:hover {
  background: var(--text-light);
  color: var(--bg-dark);
}

/* 网格系统 */
.grid {
  display: grid;
  gap: var(--spacing-lg);
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

@media (max-width: 768px) {
  .grid-3, .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
}

/* 卡片 */
.card {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
}

.card:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: var(--primary-red);
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
}

/* 视频卡片 */
.video-card {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-lg);
  aspect-ratio: 16 / 9;
  background: var(--bg-darker);
  cursor: pointer;
}

.video-card img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}

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

.video-card-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.video-card:hover .video-card-overlay {
  opacity: 1;
}

.video-play-btn {
  width: 60px;
  height: 60px;
  background: var(--primary-red);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 24px;
  transition: all 0.3s ease;
}

.video-card:hover .video-play-btn {
  transform: scale(1.1);
  background: #ff5252;
}

/* 标签 */
.tag {
  display: inline-block;
  background: rgba(211, 47, 47, 0.2);
  color: var(--primary-red);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  margin-right: var(--spacing-xs);
  margin-bottom: var(--spacing-xs);
}

/* 分隔线 */
.divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-color), transparent);
  margin: var(--spacing-2xl) 0;
}

/* 响应式文本 */
@media (max-width: 768px) {
  h1 {
    font-size: 2.5rem;
  }
  
  h2 {
    font-size: 1.875rem;
  }
  
  h3 {
    font-size: 1.5rem;
  }
}

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

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.7;
  }
}

.fade-in {
  animation: fadeIn 0.6s ease-out;
}

.slide-in-left {
  animation: slideInLeft 0.6s ease-out;
}

.slide-in-right {
  animation: slideInRight 0.6s ease-out;
}

/* 实用类 */
.text-center {
  text-align: center;
}

.text-right {
  text-align: right;
}

.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }
.mt-2xl { margin-top: var(--spacing-2xl); }

.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }
.mb-2xl { margin-bottom: var(--spacing-2xl); }

.py-lg { padding: var(--spacing-lg) 0; }
.py-xl { padding: var(--spacing-xl) 0; }
.py-2xl { padding: var(--spacing-2xl) 0; }

.opacity-50 { opacity: 0.5; }
.opacity-75 { opacity: 0.75; }

.hidden { display: none; }

/* 无障碍 */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* 导航栏 */
.navbar {
  background: linear-gradient(180deg, rgba(10, 10, 10, 0.95), rgba(10, 10, 10, 0.85));
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: var(--shadow-md);
}

.navbar-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md) 0;
}

.navbar-logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-light);
}

.logo-img {
  height: 50px;
  width: auto;
  border-radius: var(--radius-md);
}

.brand-name {
  background: linear-gradient(135deg, var(--primary-red), #ff5252);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.navbar-menu {
  display: flex;
  list-style: none;
  gap: var(--spacing-lg);
}

.navbar-menu a {
  color: var(--text-light);
  font-weight: 500;
  transition: all 0.3s ease;
  position: relative;
}

.navbar-menu a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary-red);
  transition: width 0.3s ease;
}

.navbar-menu a:hover::after {
  width: 100%;
}

.search-box {
  display: flex;
  gap: var(--spacing-xs);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--spacing-xs);
}

.search-box input {
  background: transparent;
  border: none;
  color: var(--text-light);
  padding: var(--spacing-xs) var(--spacing-sm);
  width: 200px;
  font-size: 0.9rem;
}

.search-box input::placeholder {
  color: rgba(245, 245, 245, 0.5);
}

.search-box input:focus {
  outline: none;
}

.search-btn {
  background: var(--primary-red);
  color: white;
  border: none;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-weight: 600;
  transition: all 0.3s ease;
}

.search-btn:hover {
  background: #ff5252;
  transform: scale(1.05);
}

@media (max-width: 768px) {
  .navbar-content {
    flex-direction: column;
    gap: var(--spacing-md);
  }
  
  .navbar-menu {
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-md);
  }
  
  .search-box input {
    width: 150px;
  }
}

/* Hero 区域 */
.hero {
  position: relative;
  min-height: 600px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.hero-background {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-size: cover;
  background-position: center;
  z-index: 0;
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(180deg, rgba(10, 10, 10, 0.3), rgba(10, 10, 10, 0.7));
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  color: white;
}

.hero-content h1 {
  font-size: 3.5rem;
  margin-bottom: var(--spacing-md);
  animation: slideInDown 0.8s ease-out;
}

.hero-subtitle {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-xl);
  color: rgba(255, 255, 255, 0.9);
  animation: fadeIn 0.8s ease-out 0.2s backwards;
}

.hero-cta {
  display: flex;
  gap: var(--spacing-lg);
  justify-content: center;
  animation: fadeIn 0.8s ease-out 0.4s backwards;
}

@keyframes slideInDown {
  from {
    opacity: 0;
    transform: translateY(-30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 768px) {
  .hero {
    min-height: 400px;
  }
  
  .hero-content h1 {
    font-size: 2rem;
  }
  
  .hero-subtitle {
    font-size: 1.1rem;
  }
  
  .hero-cta {
    flex-direction: column;
  }
}

/* 模块 */
.module {
  animation: fadeIn 0.6s ease-out;
}

.module h2 {
  position: relative;
  display: inline-block;
}

.module h2::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 60px;
  height: 3px;
  background: linear-gradient(90deg, var(--primary-red), transparent);
}

/* 品牌墙 */
.brand-wall {
  background: rgba(211, 47, 47, 0.1);
  border: 1px solid var(--primary-red);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  text-align: center;
}

/* 评论卡片 */
.comment-card {
  position: relative;
}

.comment-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-md);
  padding-bottom: var(--spacing-md);
  border-bottom: 1px solid var(--border-color);
}

.rating {
  color: var(--primary-red);
  font-size: 1.1rem;
}

.comment-meta {
  font-size: 0.875rem;
  color: rgba(245, 245, 245, 0.6);
  margin-top: var(--spacing-md);
}

/* FAQ */
.faq-list {
  display: grid;
  gap: var(--spacing-lg);
}

.faq-item {
  cursor: pointer;
  transition: all 0.3s ease;
}

.faq-item h3 {
  color: var(--primary-red);
  margin-bottom: var(--spacing-md);
}

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

/* 视频信息 */
.video-info {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  background: linear-gradient(180deg, transparent, rgba(0, 0, 0, 0.9));
  padding: var(--spacing-lg) var(--spacing-md);
  color: white;
}

.video-info h4 {
  margin: 0 0 var(--spacing-xs) 0;
  font-size: 1.1rem;
}

.video-info p {
  margin: 0;
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.8);
}

/* 页脚 */
.footer {
  background: linear-gradient(180deg, var(--bg-darker), rgba(0, 0, 0, 0.95));
  border-top: 1px solid var(--border-color);
  padding: var(--spacing-2xl) 0 var(--spacing-lg);
  margin-top: var(--spacing-2xl);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-2xl);
  margin-bottom: var(--spacing-2xl);
}

.footer-section h4 {
  color: var(--primary-red);
  margin-bottom: var(--spacing-md);
}

.footer-section ul {
  list-style: none;
}

.footer-section ul li {
  margin-bottom: var(--spacing-sm);
}

.footer-section a {
  color: rgba(245, 245, 245, 0.7);
  transition: color 0.3s ease;
}

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

.footer-section p {
  margin-bottom: var(--spacing-sm);
  font-size: 0.95rem;
}

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--border-color);
  color: rgba(245, 245, 245, 0.6);
  font-size: 0.9rem;
}

@media (max-width: 768px) {
  .footer-content {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
  }
}