/* 谷歌浏览器中文官网 - 全局样式 */
:root {
  --primary-color: #4285f4;
  --primary-dark: #3367d6;
  --secondary-color: #34a853;
  --warning-color: #fbbc05;
  --danger-color: #ea4335;
  --text-primary: #202124;
  --text-secondary: #5f6368;
  --bg-light: #f8f9fa;
  --bg-white: #ffffff;
  --border-color: #dadce0;
  --shadow: 0 1px 3px rgba(60,64,67,0.15), 0 1px 2px rgba(60,64,67,0.1);
  --shadow-hover: 0 4px 12px rgba(60,64,67,0.2);
  --radius: 8px;
  --radius-lg: 16px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  color: var(--text-primary);
  line-height: 1.6;
  background: var(--bg-white);
}

a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color 0.2s;
}

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

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

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

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: var(--bg-white);
  box-shadow: var(--shadow);
  z-index: 1000;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 20px;
  font-weight: 600;
  color: var(--text-primary);
}

.logo svg {
  width: 40px;
  height: 40px;
}

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

.nav a {
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 500;
  padding: 8px 0;
  border-bottom: 2px solid transparent;
  transition: all 0.2s;
}

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

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

/* Hero Section */
.hero {
  padding: 140px 0 80px;
  background: linear-gradient(135deg, #e8f0fe 0%, #ffffff 50%, #e6f4ea 100%);
  text-align: center;
}

.hero-icon {
  width: 120px;
  height: 120px;
  margin: 0 auto 32px;
}

.hero h1 {
  font-size: 48px;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.hero p {
  font-size: 20px;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 32px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  font-size: 16px;
  font-weight: 600;
  border-radius: 24px;
  border: none;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-primary {
  background: var(--primary-color);
  color: white;
}

.btn-primary:hover {
  background: var(--primary-dark);
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
}

.btn-secondary {
  background: var(--bg-white);
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

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

.btn svg {
  width: 20px;
  height: 20px;
}

.btn-group {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* Section Common */
.section {
  padding: 80px 0;
}

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

.section-title {
  text-align: center;
  margin-bottom: 48px;
}

.section-title h2 {
  font-size: 36px;
  font-weight: 700;
  margin-bottom: 16px;
}

.section-title p {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* Features Grid */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 32px;
}

.feature-card {
  background: var(--bg-white);
  padding: 32px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  transition: all 0.3s;
}

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

.feature-icon {
  width: 64px;
  height: 64px;
  margin-bottom: 20px;
  background: linear-gradient(135deg, #e8f0fe 0%, #d2e3fc 100%);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.feature-icon svg {
  width: 32px;
  height: 32px;
  color: var(--primary-color);
}

.feature-card h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 15px;
}

/* FAQ Section */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-white);
  border-radius: var(--radius);
  margin-bottom: 16px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.faq-question {
  width: 100%;
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: none;
  border: none;
  cursor: pointer;
  text-align: left;
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
  transition: background 0.2s;
}

.faq-question:hover {
  background: var(--bg-light);
}

.faq-question svg {
  width: 24px;
  height: 24px;
  color: var(--text-secondary);
  transition: transform 0.3s;
}

.faq-item.active .faq-question svg {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out;
}

.faq-item.active .faq-answer {
  max-height: 500px;
}

.faq-answer-inner {
  padding: 0 24px 20px;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* Download Section */
.download-card {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
  color: white;
  border-radius: var(--radius-lg);
  padding: 48px;
  text-align: center;
  max-width: 600px;
  margin: 0 auto;
}

.download-card h3 {
  font-size: 28px;
  margin-bottom: 16px;
}

.download-card p {
  opacity: 0.9;
  margin-bottom: 24px;
}

.download-card .btn {
  background: white;
  color: var(--primary-color);
}

.download-card .btn:hover {
  background: var(--bg-light);
  color: var(--primary-dark);
}

.download-info {
  margin-top: 24px;
  font-size: 14px;
  opacity: 0.8;
}

/* Download Page Specific */
.download-options {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
  margin-top: 48px;
}

.download-option {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 32px;
  text-align: center;
  box-shadow: var(--shadow);
  border: 2px solid transparent;
  transition: all 0.3s;
}

.download-option:hover {
  border-color: var(--primary-color);
  transform: translateY(-4px);
}

.download-option.recommended {
  border-color: var(--secondary-color);
  position: relative;
}

.download-option.recommended::before {
  content: "推荐";
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--secondary-color);
  color: white;
  padding: 4px 16px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 600;
}

.download-option svg {
  width: 64px;
  height: 64px;
  margin-bottom: 16px;
}

.download-option h3 {
  font-size: 20px;
  margin-bottom: 8px;
}

.download-option p {
  color: var(--text-secondary);
  font-size: 14px;
  margin-bottom: 20px;
}

/* Help Section */
.help-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 24px;
}

.help-card {
  background: var(--bg-white);
  padding: 24px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  display: flex;
  align-items: flex-start;
  gap: 16px;
  transition: all 0.3s;
}

.help-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
}

.help-card svg {
  width: 48px;
  height: 48px;
  flex-shrink: 0;
  color: var(--primary-color);
}

.help-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.help-card p {
  color: var(--text-secondary);
  font-size: 14px;
}

/* Steps */
.steps {
  display: flex;
  justify-content: center;
  gap: 48px;
  flex-wrap: wrap;
  margin-top: 48px;
}

.step {
  text-align: center;
  max-width: 200px;
}

.step-number {
  width: 48px;
  height: 48px;
  background: var(--primary-color);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 700;
  margin: 0 auto 16px;
}

.step h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.step p {
  color: var(--text-secondary);
  font-size: 14px;
}

/* Footer */
.footer {
  background: var(--text-primary);
  color: white;
  padding: 48px 0 24px;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand {
  max-width: 300px;
}

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

.footer-brand p {
  color: rgba(255,255,255,0.7);
  font-size: 14px;
}

.footer-links h4 {
  font-size: 16px;
  margin-bottom: 16px;
}

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

.footer-links li {
  margin-bottom: 8px;
}

.footer-links a {
  color: rgba(255,255,255,0.7);
  font-size: 14px;
  transition: color 0.2s;
}

.footer-links a:hover {
  color: white;
}

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding-top: 24px;
  text-align: center;
  color: rgba(255,255,255,0.5);
  font-size: 13px;
}

/* Responsive */
@media (max-width: 768px) {
  .header-inner {
    height: 56px;
  }

  .nav {
    display: none;
    position: absolute;
    top: 56px;
    left: 0;
    right: 0;
    background: var(--bg-white);
    flex-direction: column;
    padding: 16px;
    gap: 0;
    box-shadow: var(--shadow);
  }

  .nav.active {
    display: flex;
  }

  .nav a {
    padding: 12px 0;
    border-bottom: none;
  }

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

  .hero {
    padding: 100px 0 60px;
  }

  .hero h1 {
    font-size: 32px;
  }

  .hero p {
    font-size: 16px;
  }

  .hero-icon {
    width: 80px;
    height: 80px;
  }

  .section {
    padding: 60px 0;
  }

  .section-title h2 {
    font-size: 28px;
  }

  .steps {
    gap: 32px;
  }

  .download-card {
    padding: 32px 24px;
  }
}

/* Breadcrumb */
.breadcrumb {
  padding: 16px 0;
  background: var(--bg-light);
  margin-top: 64px;
}

.breadcrumb-list {
  display: flex;
  align-items: center;
  gap: 8px;
  list-style: none;
  font-size: 14px;
}

.breadcrumb-list li {
  display: flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb-list li::after {
  content: "/";
  color: var(--text-secondary);
}

.breadcrumb-list li:last-child::after {
  display: none;
}

.breadcrumb-list a {
  color: var(--text-secondary);
}

.breadcrumb-list span {
  color: var(--text-primary);
}

/* Table */
.table-wrapper {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-white);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

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

th {
  background: var(--bg-light);
  font-weight: 600;
}

tr:last-child td {
  border-bottom: none;
}

tr:hover td {
  background: var(--bg-light);
}

/* Alert */
.alert {
  padding: 16px 20px;
  border-radius: var(--radius);
  margin-bottom: 24px;
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.alert svg {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
}

.alert-info {
  background: #e8f0fe;
  color: var(--primary-color);
}

.alert-success {
  background: #e6f4ea;
  color: var(--secondary-color);
}

.alert-warning {
  background: #fef7e0;
  color: #f9ab00;
}