/* ============================================
   隐私协议和服务条款页面 - 现代化样式文件
   ============================================ */

/* --------------------------------------------
   1. 全局基础样式 & CSS 变量
   -------------------------------------------- */
@font-face {
  font-family: btfFont;
}

:root {
  /* 浅色主题变量 */
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --accent-color: #3b82f6;
  --accent-hover: #2563eb;
  --border-color: #e2e8f0;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md:
    0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg:
    0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

/* --------------------------------------------
   2. 主题切换按钮（现代化设计）
   -------------------------------------------- */
.theme-toggle-btn {
  position: relative;
  width: 50px;
  height: 50px;
  border: 2px solid var(--border-color);
  border-radius: 50%;
  background: var(--bg-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
  z-index: 100;
}

.theme-toggle-btn:hover {
  transform: scale(1.1) rotate(15deg);
  border-color: var(--accent-color);
  box-shadow: var(--shadow-md);
}

.theme-toggle-btn svg {
  transition: var(--transition);
  color: var(--text-primary);
}

.theme-toggle-btn:hover svg {
  color: var(--accent-color);
}

/* --------------------------------------------
   3. 主容器布局
   -------------------------------------------- */
main {
  min-height: 100vh;
  padding: 2rem 1rem;
  background: linear-gradient(
    135deg,
    rgba(102, 126, 234, 0.05) 0%,
    rgba(118, 75, 162, 0.05) 100%
  );
}

.terms-container {
  max-width: 900px;
  margin: 0 auto;
  padding: 3rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  backdrop-filter: blur(10px);
  transition: var(--transition);
}

.terms-container:hover {
  box-shadow:
    0 20px 25px -5px rgba(0, 0, 0, 0.1),
    0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

/* --------------------------------------------
   4. 标题区域样式
   -------------------------------------------- */
.terms-title {
  text-align: center;
  font-size: clamp(1.5rem, 4vw, 2.25rem);
  font-weight: 700;
  color: var(--text-primary);
  margin: 2rem 0 1rem;
  padding-bottom: 1.5rem;
  border-bottom: 3px solid transparent;
  background: var(--gradient-primary);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: -0.025em;
}

.terms-date {
  text-align: right;
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 3rem;
  font-weight: 500;
  padding: 0.75rem 1rem;
  background: rgba(59, 130, 246, 0.05);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--accent-color);
}

/* --------------------------------------------
   5. 章节标题样式
   -------------------------------------------- */
.terms-container section {
  margin-bottom: 3rem;
  animation: fadeInUp 0.6s ease-out;
}

.terms-container h2 {
  font-size: clamp(1.25rem, 3vw, 1.75rem);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 2px solid var(--border-color);
  position: relative;
  transition: var(--transition);
}

.terms-container h2::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 60px;
  height: 2px;
  background: var(--gradient-primary);
  transition: var(--transition);
}

.terms-container h2:hover::after {
  width: 100px;
}

/* --------------------------------------------
   6. 段落和列表样式优化
   -------------------------------------------- */
.terms-container p {
  text-indent: 2em;
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: 1rem;
  font-size: clamp(0.9rem, 2vw, 1rem);
  transition: var(--transition);
}

.terms-container p:hover {
  color: var(--text-primary);
}

.terms-container ul {
  margin: 1.5rem 0 1.5rem 2.5rem;
  list-style: none;
  padding: 0;
}

.terms-container ul li {
  position: relative;
  padding-left: 1.5rem;
  margin-bottom: 0.75rem;
  line-height: 1.8;
  color: var(--text-secondary);
  transition: var(--transition);
}

.terms-container ul li::before {
  content: "▸";
  position: absolute;
  left: 0;
  color: var(--accent-color);
  font-weight: bold;
  transition: var(--transition);
}

.terms-container ul li:hover {
  color: var(--text-primary);
  transform: translateX(5px);
}

.terms-container ul li:hover::before {
  color: var(--accent-hover);
}

/* --------------------------------------------
   7. 页脚样式
   -------------------------------------------- */
footer {
  margin-top: 4rem !important;
  padding-top: 2rem;
  border-top: 2px solid var(--border-color);
  text-align: right;
}

footer h4 {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-bottom: 0.75rem;
  font-weight: 500;
  transition: var(--transition);
}

footer h4:last-child {
  margin-bottom: 0;
}

footer h4:hover {
  color: var(--accent-color);
}

/* --------------------------------------------
   8. 动画效果
   -------------------------------------------- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* 章节交错动画延迟 */
.terms-container section:nth-child(1) {
  animation-delay: 0.1s;
}
.terms-container section:nth-child(2) {
  animation-delay: 0.2s;
}
.terms-container section:nth-child(3) {
  animation-delay: 0.3s;
}
.terms-container section:nth-child(4) {
  animation-delay: 0.4s;
}
.terms-container section:nth-child(5) {
  animation-delay: 0.5s;
}

/* --------------------------------------------
   9. 夜间模式样式（增强版）
   -------------------------------------------- */
body.dark-mode {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --accent-color: #60a5fa;
  --accent-hover: #3b82f6;
  --border-color: #334155;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow-md:
    0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
  --shadow-lg:
    0 10px 15px -3px rgba(0, 0, 0, 0.5), 0 4px 6px -2px rgba(0, 0, 0, 0.4);
}

body.dark-mode main {
  background: linear-gradient(
    135deg,
    rgba(15, 23, 42, 0.8) 0%,
    rgba(30, 41, 59, 0.8) 100%
  );
}

body.dark-mode .terms-date {
  background: rgba(96, 165, 250, 0.1);
}

body.dark-mode .theme-toggle-btn svg {
  color: var(--text-primary);
}

/* --------------------------------------------
   10. 响应式设计（移动端适配）
   -------------------------------------------- */
@media screen and (max-width: 768px) {
  main {
    padding: 1rem 0.5rem;
  }

  .terms-container {
    padding: 2rem 1.5rem;
    width: 95vw;
    border-radius: var(--radius-md);
  }

  .terms-title {
    font-size: 1.5rem;
    margin: 1.5rem 0 0.75rem;
  }

  .terms-date {
    font-size: 0.8rem;
    margin-bottom: 2rem;
    text-align: left;
  }

  .terms-container h2 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
  }

  .terms-container p {
    font-size: 0.9rem;
    text-indent: 1.5em;
  }

  .terms-container ul {
    margin-left: 1.5rem;
  }

  footer {
    text-align: center;
    margin-top: 3rem !important;
  }

  footer h4 {
    font-size: 0.9rem;
  }

  .theme-toggle-btn {
    width: 45px;
    height: 45px;
    left: 5% !important;
  }
}

@media screen and (max-width: 480px) {
  .terms-container {
    padding: 1.5rem 1rem;
    width: 98vw;
  }

  .terms-title {
    font-size: 1.25rem;
  }

  .terms-container h2 {
    font-size: 1.1rem;
  }

  .terms-container p {
    font-size: 0.85rem;
    line-height: 1.7;
  }

  .terms-container ul li {
    font-size: 0.85rem;
  }

  footer h4 {
    font-size: 0.85rem;
  }
}

/* --------------------------------------------
   11. 打印样式优化
   -------------------------------------------- */
@media print {
  body {
    background: white;
    color: black;
  }

  .terms-container {
    box-shadow: none;
    border: 1px solid #ccc;
  }

  .theme-toggle-btn {
    display: none;
  }

  main {
    background: white;
  }
}

/* --------------------------------------------
   12. 辅助类和特殊效果
   -------------------------------------------- */
/* 链接悬停效果 */
.terms-link {
  cursor: default;
}

/* 平滑滚动 */
html {
  scroll-behavior: smooth;
}

/* 选中文本样式 */
::selection {
  background: rgba(59, 130, 246, 0.3);
  color: var(--text-primary);
}

::-moz-selection {
  background: rgba(59, 130, 246, 0.3);
  color: var(--text-primary);
}