/* ============================================================
   Chrome 安全下载站 - 全局样式表
   设计理念：现代极简、清晰层级、流畅动效
   ============================================================ */

/* ---------- CSS 变量 ---------- */
:root {
  --color-primary: #1a73e8;
  --color-primary-dark: #1557b0;
  --color-primary-light: #e8f0fe;
  --color-accent: #00c853;
  --color-accent-light: #e6f9ed;
  --color-text-primary: #202124;
  --color-text-secondary: #5f6368;
  --color-text-muted: #80868b;
  --color-bg: #ffffff;
  --color-bg-alt: #f8f9fa;
  --color-bg-dark: #f1f3f4;
  --color-border: #dadce0;
  --color-border-light: #e8eaed;
  --color-card-shadow: 0 1px 2px 0 rgba(60,64,67,0.08), 0 1px 6px 1px rgba(60,64,67,0.06);
  --color-card-shadow-hover: 0 4px 12px 0 rgba(60,64,67,0.12), 0 1px 6px 1px rgba(60,64,67,0.08);
  --font-family: 'Segoe UI', system-ui, -apple-system, BlinkMacSystemFont, Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, 'Courier New', monospace;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --transition-fast: 0.15s ease;
  --transition-base: 0.25s ease;
  --transition-slow: 0.4s ease;
  --max-width: 1200px;
  --nav-height: 64px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family);
  color: var(--color-text-primary);
  background-color: var(--color-bg);
  line-height: 1.6;
  overflow-x: hidden;
}

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

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

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

/* ---------- 工具类 ---------- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
}

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

.hidden { display: none !important; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-base);
  line-height: 1.4;
  white-space: nowrap;
}

.btn:disabled {
  opacity: 0.7;
  cursor: not-allowed;
}

.btn--primary {
  background-color: var(--color-primary);
  color: #fff;
  box-shadow: 0 1px 3px rgba(26,115,232,0.3);
}

.btn--primary:hover {
  background-color: var(--color-primary-dark);
  box-shadow: 0 4px 12px rgba(26,115,232,0.4);
  transform: translateY(-1px);
  color: #fff;
}

.btn--accent {
  background-color: var(--color-accent);
  color: #fff;
  box-shadow: 0 1px 3px rgba(0,200,83,0.3);
}

.btn--accent:hover {
  background-color: #00a344;
  box-shadow: 0 4px 12px rgba(0,200,83,0.4);
  transform: translateY(-1px);
  color: #fff;
}

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

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

.btn--large {
  padding: 16px 40px;
  font-size: 1.125rem;
  border-radius: var(--radius-md);
}

.btn--small {
  padding: 8px 20px;
  font-size: 0.875rem;
}

/* ---------- spin 动画（下载按钮 loading 必需） ---------- */
@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.6; }
}

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

.animate-pulse {
  animation: pulse 2s ease-in-out infinite;
}

/* ---------- 导航栏 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border-light);
  height: var(--nav-height);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.site-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-text-primary);
}

.site-logo svg {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

.site-logo:hover {
  color: var(--color-text-primary);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.site-nav__link {
  display: inline-flex;
  align-items: center;
  padding: 8px 18px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.site-nav__link:hover {
  background-color: var(--color-bg-dark);
  color: var(--color-text-primary);
}

.site-nav__link--active {
  background-color: var(--color-primary-light);
  color: var(--color-primary);
  font-weight: 600;
}

.site-nav__link--active:hover {
  background-color: #d2e3fc;
  color: var(--color-primary-dark);
}

/* 移动端菜单按钮 */
.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  color: var(--color-text-secondary);
}

/* ---------- 页脚 ---------- */
.site-footer {
  background-color: var(--color-bg-alt);
  border-top: 1px solid var(--color-border-light);
  padding: 48px 0 32px;
  margin-top: 80px;
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand {
  max-width: 320px;
}

.footer-brand__logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--color-text-primary);
  margin-bottom: 12px;
}

.footer-brand__desc {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

.footer-links h4 {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

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

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  font-size: 0.875rem;
  color: var(--color-text-secondary);
}

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

.footer-bottom {
  border-top: 1px solid var(--color-border-light);
  padding-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-bottom__disclaimer {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.875rem;
  color: var(--color-text-secondary);
}

.footer-bottom__disclaimer svg {
  width: 18px;
  height: 18px;
  color: var(--color-accent);
  flex-shrink: 0;
}

.footer-bottom__copyright {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
}

/* ---------- 通用板块 ---------- */
.section {
  padding: 80px 0;
}

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

.section-header {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 56px;
}

.section-header h2 {
  font-size: 2.25rem;
  font-weight: 700;
  color: var(--color-text-primary);
  margin-bottom: 16px;
  line-height: 1.3;
}

.section-header p {
  font-size: 1.125rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ---------- 卡片 ---------- */
.card {
  background: var(--color-bg);
  border-radius: var(--radius-md);
  padding: 32px;
  box-shadow: var(--color-card-shadow);
  transition: all var(--transition-base);
  border: 1px solid var(--color-border-light);
}

.card:hover {
  box-shadow: var(--color-card-shadow-hover);
  transform: translateY(-3px);
}

.card__icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background-color: var(--color-primary-light);
  color: var(--color-primary);
  margin-bottom: 20px;
}

.card__icon--accent {
  background-color: var(--color-accent-light);
  color: var(--color-accent);
}

.card__icon svg {
  width: 24px;
  height: 24px;
}

.card h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--color-text-primary);
}

.card p {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* ---------- 评分星星 ---------- */
.stars {
  display: flex;
  gap: 3px;
  color: #fbbc04;
}

.stars svg {
  width: 16px;
  height: 16px;
}

/* ---------- FAQ ---------- */
.faq-item {
  border-bottom: 1px solid var(--color-border-light);
}

.faq-item__question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 0;
  background: none;
  border: none;
  text-align: left;
  cursor: pointer;
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--color-text-primary);
  transition: color var(--transition-fast);
}

.faq-item__question:hover {
  color: var(--color-primary);
}

.faq-item__question svg {
  width: 20px;
  height: 20px;
  color: var(--color-text-muted);
  transition: transform var(--transition-base);
  flex-shrink: 0;
  margin-left: 16px;
}

.faq-item.is-open .faq-item__question svg {
  transform: rotate(180deg);
}

.faq-item__answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-slow), padding var(--transition-slow);
}

.faq-item.is-open .faq-item__answer {
  max-height: 500px;
  padding-bottom: 24px;
}

.faq-item__answer p {
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  line-height: 1.8;
}

.faq-item__answer ul,
.faq-item__answer ol {
  margin: 12px 0 12px 20px;
  color: var(--color-text-secondary);
  font-size: 0.9375rem;
  line-height: 1.8;
}

.faq-item__answer li {
  margin-bottom: 6px;
}

/* ---------- 表格 ---------- */
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9375rem;
}

.data-table th,
.data-table td {
  padding: 16px 20px;
  text-align: left;
  border-bottom: 1px solid var(--color-border-light);
}

.data-table th {
  font-weight: 600;
  color: var(--color-text-primary);
  background-color: var(--color-bg-dark);
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.data-table td {
  color: var(--color-text-secondary);
}

.data-table tr:hover td {
  background-color: var(--color-bg-alt);
}

.data-table td strong {
  color: var(--color-text-primary);
}

.check-yes {
  color: var(--color-accent);
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.check-no {
  color: #ea4335;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

/* ---------- 标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  border-radius: 100px;
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.tag--primary {
  background-color: var(--color-primary-light);
  color: var(--color-primary);
}

.tag--accent {
  background-color: var(--color-accent-light);
  color: var(--color-accent);
}

/* ---------- 徽章 ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background-color: var(--color-bg-dark);
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-secondary);
}

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .footer-content {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  :root {
    --nav-height: 56px;
  }

  .container {
    padding-left: 16px;
    padding-right: 16px;
  }

  .section {
    padding: 56px 0;
  }

  .section-header h2 {
    font-size: 1.75rem;
  }

  .section-header p {
    font-size: 1rem;
  }

  .btn--large {
    padding: 14px 28px;
    font-size: 1rem;
  }

  .mobile-menu-btn {
    display: block;
  }

  .site-nav {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: rgba(255,255,255,0.98);
    backdrop-filter: blur(12px);
    flex-direction: column;
    padding: 16px;
    gap: 8px;
    border-bottom: 1px solid var(--color-border-light);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
  }

  .site-nav.is-open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .site-nav__link {
    width: 100%;
    padding: 12px 16px;
  }

  .footer-content {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .footer-bottom {
    text-align: center;
  }

  .data-table {
    font-size: 0.875rem;
  }

  .data-table th,
  .data-table td {
    padding: 12px 14px;
  }
}

@media (max-width: 480px) {
  .section-header h2 {
    font-size: 1.5rem;
  }

  .card {
    padding: 24px;
  }

  .btn {
    width: 100%;
  }
}

/* ---------- 打印优化 ---------- */
@media print {
  .site-header,
  .site-footer,
  .btn,
  .faq-item__question svg {
    display: none !important;
  }

  .faq-item__answer {
    max-height: none !important;
    padding-bottom: 16px !important;
  }
}