/* ============================================
   UI Design System - Modern Card Layout
   瀑布流卡片布局 + 毛玻璃效果 + 微交互动效
   ============================================ */

/* -------------------- CSS变量定义 -------------------- */
:root {
  /* 主色调 */
  --primary-100: #e0e7ff;
  --primary-200: #c7d2fe;
  --primary-400: #818cf8;
  --primary-500: #6366f1;
  --primary-600: #4f46e5;
  --primary-700: #4338ca;
  
  /* 渐变色 */
  --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-bg: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
  --gradient-card: linear-gradient(180deg, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0.05) 100%);
  --gradient-text: linear-gradient(90deg, #00d4ff, #7c3aed);
  
  /* 毛玻璃效果 */
  --glass-bg: rgba(255, 255, 255, 0.08);
  --glass-border: rgba(255, 255, 255, 0.18);
  --glass-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
  
  /* 间距 */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2rem;
  --space-xl: 3rem;
  --space-2xl: 4rem;
  
  /* 圆角 */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  
  /* 阴影 */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.12);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.16);
  --shadow-glow: 0 0 40px rgba(99, 102, 241, 0.3);
  
  /* 字体 */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-display: 'Poppins', var(--font-sans);
  
  /* 过渡 */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  color: #e2e8f0;
  background: var(--gradient-bg);
  min-height: 100vh;
  overflow-x: hidden;
}

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

ul, ol {
  list-style: none;
}

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

button, input, textarea, select {
  font-family: inherit;
  font-size: inherit;
  outline: none;
  border: none;
}

/* -------------------- 滚动条样式 -------------------- */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: rgba(255, 255, 255, 0.05);
}

::-webkit-scrollbar-thumb {
  background: var(--primary-500);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--primary-400);
}

/* -------------------- 容器与布局 -------------------- */
.container {
  width: 100%;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.section {
  padding: var(--space-2xl) 0;
}

/* -------------------- 瀑布流布局 -------------------- */
.masonry-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
  grid-auto-flow: dense;
}

.masonry-grid .card:nth-child(5n+1) { grid-row: span 2; }
.masonry-grid .card:nth-child(3n+1) { grid-column: span 2; }
.masonry-grid .card:nth-child(7n+1) { grid-row: span 2; grid-column: span 2; }

/* 响应式瀑布流 */
@media (max-width: 1200px) {
  .masonry-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (max-width: 900px) {
  .masonry-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .masonry-grid .card:nth-child(3n+1) { grid-column: span 1; }
  .masonry-grid .card:nth-child(7n+1) { grid-row: span 1; grid-column: span 2; }
}

@media (max-width: 600px) {
  .masonry-grid {
    grid-template-columns: 1fr;
    gap: var(--space-sm);
  }
  
  .masonry-grid .card:nth-child(7n+1) { grid-column: span 1; }
}

/* -------------------- 头部导航 -------------------- */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: var(--space-sm) 0;
  background: rgba(26, 26, 46, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--glass-border);
  transition: all var(--transition-normal);
}

.header.scrolled {
  padding: var(--space-xs) 0;
  background: rgba(26, 26, 46, 0.95);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header__logo {
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 700;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header__nav {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.header__nav-link {
  position: relative;
  font-weight: 500;
  color: #94a3b8;
  padding: var(--space-xs) 0;
  transition: color var(--transition-fast);
}

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

.header__nav-link:hover {
  color: #fff;
}

.header__nav-link:hover::after {
  width: 100%;
}

.header__nav-link.active {
  color: #fff;
}

.header__nav-link.active::after {
  width: 100%;
}

/* 移动端菜单按钮 */
.header__menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 10px;
  background: transparent;
  cursor: pointer;
}

.header__menu-btn span {
  display: block;
  width: 24px;
  height: 2px;
  background: #fff;
  transition: all var(--transition-normal);
}

@media (max-width: 768px) {
  .header__menu-btn {
    display: flex;
  }
  
  .header__nav {
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    flex-direction: column;
    background: rgba(26, 26, 46, 0.98);
    backdrop-filter: blur(20px);
    padding: var(--space-md);
    gap: var(--space-sm);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: all var(--transition-normal);
  }
  
  .header__nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
}

/* -------------------- Hero 区域 -------------------- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  position: relative;
  overflow: hidden;
  padding-top: 80px;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 30% 30%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
              radial-gradient(circle at 70% 70%, rgba(118, 75, 162, 0.15) 0%, transparent 50%);
  animation: float 20s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translate(0, 0) rotate(0deg); }
  50% { transform: translate(-2%, -2%) rotate(1deg); }
}

.hero__content {
  position: relative;
  z-index: 1;
  max-width: 900px;
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: 8px 20px;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 50px;
  font-size: 0.875rem;
  color: var(--primary-400);
  margin-bottom: var(--space-md);
  backdrop-filter: blur(10px);
}

.hero__title {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 8vw, 5rem);
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: var(--space-md);
  letter-spacing: -0.02em;
}

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

.hero__description {
  font-size: 1.25rem;
  color: #94a3b8;
  max-width: 600px;
  margin: 0 auto var(--space-lg);
}

.hero__cta {
  display: flex;
  gap: var(--space-sm);
  justify-content: center;
  flex-wrap: wrap;
}

/* -------------------- 卡片组件 -------------------- */
.card {
  position: relative;
  background: var(--gradient-card);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-normal);
  cursor: pointer;
}

.card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(255,255,255,0.1) 0%, transparent 50%);
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.card:hover {
  transform: translateY(-8px);
  border-color: var(--primary-400);
  box-shadow: var(--shadow-lg), var(--shadow-glow);
}

.card:hover::before {
  opacity: 1;
}

.card__image {
  position: relative;
  width: 100%;
  padding-top: 66.67%;
  overflow: hidden;
}

.card__image img {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.card:hover .card__image img {
  transform: scale(1.08);
}

.card__overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 0%, rgba(0,0,0,0.6) 100%);
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.card:hover .card__overlay {
  opacity: 1;
}

.card__content {
  padding: var(--space-md);
}

.card__tag {
  display: inline-block;
  padding: 4px 12px;
  background: var(--primary-600);
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 600;
  color: #fff;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-xs);
}

.card__title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  line-height: 1.3;
  margin-bottom: var(--space-xs);
  color: #fff;
}

.card__desc {
  font-size: 0.875rem;
  color: #94a3b8;
  line-height: 1.6;
}

.card__footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-sm) var(--space-md);
  border-top: 1px solid rgba(255,255,255,0.08);
}

.card__author {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.card__avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 600;
  color: #fff;
}

.card__meta {
  font-size: 0.75rem;
  color: #64748b;
}

.card__actions {
  display: flex;
  gap: var(--space-xs);
  opacity: 0;
  transform: translateY(10px);
  transition: all var(--transition-normal);
}

.card:hover .card__actions {
  opacity: 1;
  transform: translateY(0);
}

.card__action-btn {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255,255,255,0.1);
  border-radius: 50%;
  color: #fff;
  transition: all var(--transition-fast);
}

.card__action-btn:hover {
  background: var(--primary-500);
  transform: scale(1.1);
}

/* -------------------- 按钮组件 -------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  padding: 14px 32px;
  font-weight: 600;
  font-size: 0.9375rem;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(255,255,255,0.15) 0%, transparent 50%);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.btn:hover::before {
  opacity: 1;
}

.btn--primary {
  background: var(--gradient-primary);
  color: #fff;
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.4);
}

.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(99, 102, 241, 0.5);
}

.btn--primary:active {
  transform: translateY(0);
}

.btn--secondary {
  background: var(--glass-bg);
  backdrop-filter: blur(10px);
  color: #fff;
  border: 1px solid var(--glass-border);
}

.btn--secondary:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: var(--primary-400);
  transform: translateY(-2px);
}

.btn--ghost {
  background: transparent;
  color: #94a3b8;
}

.btn--ghost:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.05);
}

.btn--icon {
  width: 48px;
  height: 48px;
  padding: 0;
  border-radius: 50%;
}

.btn--sm {
  padding: 10px 20px;
  font-size: 0.8125rem;
}

.btn--lg {
  padding: 18px 40px;
  font-size: 1.0625rem;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none !important;
}

/* -------------------- 表单组件 -------------------- */
.form-group {
  margin-bottom: var(--space-md);
}

.form-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  color: #94a3b8;
  margin-bottom: var(--space-xs);
}

.form-input {
  width: 100%;
  padding: 14px 18px;
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-md);
  color: #fff;
  font-size: 1rem;
  transition: all var(--transition-fast);
}

.form-input::placeholder {
  color: #475569;
}

.form-input:hover {
  border-color: rgba(255, 255, 255, 0.2);
}

.form-input:focus {
  border-color: var(--primary-500);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
  background: rgba(15, 23, 42, 0.8);
}

.form-input--error {
  border-color: #ef4444;
}

.form-input--error:focus {
  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.2);
}

.form-error {
  font-size: 0.8125rem;
  color: #ef4444;
  margin-top: var(--space-xs);
}

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

.form-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='%2394a3b8' 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 14px center;
  background-size: 18px;
  padding-right: 50px;
}

.form-checkbox {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  cursor: pointer;
}

.form-checkbox input {
  width: 20px;
  height: 20px;
  appearance: none;
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 4px;
  cursor: pointer;
  transition: all var(--transition-fast);
  position: relative;
}

.form-checkbox input:checked {
  background: var(--primary-500);
  border-color: var(--primary-500);
}

.form-checkbox input:checked::after {
  content: '✓';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: #fff;
  font-size: 0.75rem;
  font-weight: bold;
}

/* -------------------- 几何装饰元素 -------------------- */
.decorations {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.decoration {
  position: absolute;
  opacity: 0.1;
}

.decoration--circle {
  width: 400px;
  height: 400px;
  border: 2px solid var(--primary-400);
  border-radius: 50%;
}

.decoration--circle-1 {
  top: -200px;
  right: -100px;
}

.decoration--circle-2 {
  bottom: -150px;
  left: -150px;
  width: 300px;
  height: 300px;
}

.decoration--triangle {
  width: 0;
  height: 0;
  border-left: 100px solid transparent;
  border-right: 100px solid transparent;
  border-bottom: 173px solid var(--primary-500);
}

.decoration--triangle-1 {
  top: 20%;
  left: 5%;
}

.decoration--square {
  width: 200px;
  height: 200px;
  border: 2px solid var(--primary-500);
  transform: rotate(45deg);
}

.decoration--square-1 {
  bottom: 10%;
  right: 10%;
}

.decoration--line {
  width: 300px;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--primary-400), transparent);
}

.decoration--line-1 {
  top: 30%;
  right: 10%;
  transform: rotate(-30deg);
}

/* -------------------- 标签与徽章 -------------------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 50px;
  font-size: 0.8125rem;
  font-weight: 500;
  color: #e2e8f0;
  backdrop-filter: blur(10px);
}

.badge--primary {
  background: var(--primary-600);
  border-color: var(--primary-500);
  color: #fff;
}

.badge--success {
  background: rgba(16, 185, 129, 0.2);
  border-color: #10b981;
  color: #10b981;
}

.badge--warning {
  background: rgba(245, 158, 11, 0.2);
  border-color: #f59e0b;
  color: #f59e0b;
}

.badge--danger {
  background: rgba(239, 68, 68, 0.2);
  border-color: #ef4444;
  color: #ef4444;
}

/* -------------------- 工具提示 -------------------- */
.tooltip {
  position: relative;
}

.tooltip::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(-8px);
  padding: 8px 14px;
  background: #1e293b;
  color: #fff;
  font-size: 0.8125rem;
  white-space: nowrap;
  border-radius: var(--radius-sm);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-fast);
  pointer-events: none;
  z-index: 100;
}

.tooltip:hover::after {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(-4px);
}

/* -------------------- 模态框 -------------------- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-md);
  z-index: 2000;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal {
  width: 100%;
  max-width: 500px;
  max-height: 90vh;
  overflow-y: auto;
  background: rgba(30, 41, 59, 0.95);
  backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-xl);
  transform: scale(0.9) translateY(20px);
  transition: transform var(--transition-normal);
}

.modal-overlay.active .modal {
  transform: scale(1) translateY(0);
}

.modal__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md);
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.modal__title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  color: #fff;
}

.modal__close {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255,255,255,0.05);
  border-radius: 50%;
  color: #94a3b8;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.modal__close:hover {
  background: rgba(255,255,255,0.1);
  color: #fff;
}

.modal__body {
  padding: var(--space-md);
}

.modal__footer {
  display: flex;
  gap: var(--space-sm);
  justify-content: flex-end;
  padding: var(--space-md);
  border-top: 1px solid rgba(255,255,255,0.08);
}

/* -------------------- 加载动画 -------------------- */
.spinner {
  width: 24px;
  height: 24px;
  border: 2px solid rgba(255,255,255,0.2);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.skeleton {
  background: linear-gradient(90deg, 
    rgba(255,255,255,0.05) 0%, 
    rgba(255,255,255,0.1) 50%, 
    rgba(255,255,255,0.05) 100%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: var(--radius-sm);
}

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.skeleton--image {
  width: 100%;
  padding-top: 66.67%;
}

.skeleton--text {
  height: 16px;
  margin-bottom: 8px;
}

.skeleton--text:last-child {
  width: 70%;
}

/* -------------------- 分页 -------------------- */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  margin-top: var(--space-xl);
}

.pagination__btn {
  min-width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--glass-bg);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: var(--radius-md);
  color: #94a3b8;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.pagination__btn:hover {
  background: rgba(255,255,255,0.12);
  color: #fff;
  border-color: var(--primary-500);
}

.pagination__btn.active {
  background: var(--primary-500);
  border-color: var(--primary-500);
  color: #fff;
}

.pagination__btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.pagination__dots {
  color: #64748b;
  padding: 0 var(--space-xs);
}

/* -------------------- 页脚 -------------------- */
.footer {
  background: rgba(15, 23, 42, 0.8);
  backdrop-filter: blur(20px);
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: var(--space-2xl) 0 var(--space-lg);
  margin-top: var(--space-2xl);
}

.footer__grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: var(--space-xl);
  margin-bottom: var(--space-xl);
}

@media (max-width: 900px) {
  .footer__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 600px) {
  .footer__grid {
    grid-template-columns: 1fr;
  }
}

.footer__brand {
  max-width: 300px;
}

.footer__logo {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--space-sm);
}

.footer__desc {
  font-size: 0.875rem;
  color: #64748b;
  line-height: 1.7;
}

.footer__title {
  font-size: 0.875rem;
  font-weight: 600;
  color: #fff;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-md);
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.footer__link {
  font-size: 0.875rem;
  color: #94a3b8;
  transition: all var(--transition-fast);
}

.footer__link:hover {
  color: #fff;
  padding-left: 4px;
}

.footer__social {
  display: flex;
  gap: var(--space-xs);
}

.footer__social-link {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--glass-bg);
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 50%;
  color: #94a3b8;
  transition: all var(--transition-fast);
}

.footer__social-link:hover {
  background: var(--primary-500);
  border-color: var(--primary-500);
  color: #fff;
  transform: translateY(-2px);
}

.footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-lg);
  border-top: 1px solid rgba(255,255,255,0.08);
  font-size: 0.8125rem;
  color: #64748b;
}

@media (max-width: 600px) {
  .footer__bottom {
    flex-direction: column;
    gap: var(--space-sm);
    text-align: center;
  }
}

/* -------------------- 动画 -------------------- */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

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

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

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-50px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(50px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

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

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

.animate-scale-in {
  animation: scaleIn 0.5s ease forwards;
}

/* 延迟动画 */
.delay-100 { animation-delay: 0.1s; }
.delay-200 { animation-delay: 0.2s; }
.delay-300 { animation-delay: 0.3s; }
.delay-400 { animation-delay: 0.4s; }
.delay-500 { animation-delay: 0.5s; }

/* -------------------- 工具类 -------------------- */
.text-gradient {
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.glass {
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
}

.hidden { display: none !important; }
.invisible { visibility: hidden; }

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }

.text-center { text-align: center; }
.text-sm { font-size: 0.875rem; }
.text-xs { font-size: 0.75rem; }
.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold { font-weight: 700; }

.text-muted { color: #64748b; }
.text-primary { color: var(--primary-400); }
.text-white { color: #fff; }

.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }

/* -------------------- 响应式工具 -------------------- */
@media (max-width: 768px) {
  .hide-mobile { display: none !important; }
  
  .section {
    padding: var(--space-xl) 0;
  }
  
  .hero__title {
    font-size: 2.5rem;
  }
  
  .hero__description {
    font-size: 1.0625rem;
  }
}

@media (min-width: 769px) {
  .show-mobile { display: none !important; }
}
```