/* ═══════════════════════════════════════════════
   Google Chrome 下载站 — 组件样式表
   按钮、卡片、导航栏、折叠面板、标签切换等
   ═══════════════════════════════════════════════ */

/* ── 导航栏 ── */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: 1000;
  background: transparent;
  transition: var(--transition-default);
}

.navbar.scrolled {
  background: var(--nav-scroll-bg);
  box-shadow: var(--nav-scroll-shadow);
}

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

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
}

.navbar-brand svg {
  width: 32px;
  height: 32px;
}

.navbar-menu {
  display: flex;
  align-items: center;
  gap: 8px;
}

.navbar-item {
  display: block;
  padding: 8px 16px;
  font-size: 15px;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-input);
  transition: var(--transition-default);
  position: relative;
}

.navbar-item:hover {
  color: var(--color-primary);
  background: var(--bg-secondary);
}

.navbar-item.active {
  color: var(--color-primary-dark);
  font-weight: 600;
}

.navbar-item.active::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 16px;
  right: 16px;
  height: 3px;
  background: var(--color-primary);
  border-radius: 2px;
}

/* ── 汉堡菜单 ── */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  background: none;
  border: none;
  cursor: pointer;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition-default);
}

.hamburger.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
}

.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* 移动端导航 */
@media (max-width: 768px) {
  .hamburger {
    display: flex;
  }

  .navbar-menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: #ffffff;
    flex-direction: column;
    padding: 16px;
    gap: 4px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: all 0.3s ease;
  }

  .navbar-menu.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .navbar-item {
    width: 100%;
    padding: 12px 16px;
    border-left: 3px solid transparent;
    border-radius: 0;
  }

  .navbar-item.active {
    border-left-color: var(--color-accent);
    background: var(--bg-secondary);
  }

  .navbar-item.active::after {
    display: none;
  }
}

/* ── 按钮组件 ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  font-size: 16px;
  font-weight: 600;
  border-radius: var(--radius-btn);
  cursor: pointer;
  transition: var(--transition-default);
  min-height: 44px;
  min-width: 44px;
  text-align: center;
}

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

.btn-primary {
  background: var(--btn-gradient);
  color: #ffffff;
  border: none;
  box-shadow: 0 2px 8px rgba(5, 150, 105, 0.2);
}

.btn-primary:hover:not(:disabled) {
  filter: brightness(1.1);
  box-shadow: var(--btn-shadow);
  transform: translateY(-1px);
}

.btn-secondary {
  background: #ffffff;
  color: var(--color-primary-dark);
  border: 1.5px solid var(--color-primary);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--bg-secondary);
  border-color: var(--color-primary-dark);
}

.btn-large {
  padding: 16px 40px;
  font-size: 18px;
}

.btn-full {
  width: 100%;
}

/* ── 卡片组件 ── */
.card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-card);
  padding: 32px;
  box-shadow: var(--card-shadow);
  transition: var(--transition-default);
}

.card:hover {
  transform: translateY(-5px);
  border-color: var(--card-border-hover);
  box-shadow: var(--card-shadow-hover);
}

.card-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 20px;
  color: var(--color-primary);
  transition: transform 0.3s ease;
}

.card:hover .card-icon {
  transform: scale(1.1);
}

.card-title {
  font-size: 20px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.card-text {
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-secondary);
}

/* ── 网格布局 ── */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

@media (max-width: 1024px) {
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

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

/* ── 徽章组件 ── */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 14px;
  font-size: 13px;
  font-weight: 600;
  background: var(--badge-bg);
  color: var(--badge-text);
  border-radius: var(--radius-badge);
  animation: breathe 2s ease-in-out infinite;
}

/* ── 步骤编号 ── */
.step-number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  min-width: 40px;
  background: var(--color-accent);
  color: #ffffff;
  font-size: 16px;
  font-weight: 600;
  border-radius: 50%;
  transition: transform 0.5s ease;
}

.step-item:hover .step-number {
  transform: rotate(360deg);
}

/* ── 步骤卡片 ── */
.step-item {
  display: flex;
  gap: 20px;
  padding: 24px;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-card);
  margin-bottom: 16px;
  transition: var(--transition-default);
}

.step-item:hover {
  border-color: var(--card-border-hover);
  box-shadow: var(--card-shadow-hover);
}

.step-content h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.step-content p {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-secondary);
}

/* ── 折叠面板(FAQ) ── */
.faq-item {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 12px;
  margin-bottom: 12px;
  overflow: hidden;
  transition: var(--transition-default);
}

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

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 20px 24px;
  font-size: 16px;
  font-weight: 500;
  color: var(--text-primary);
  background: none;
  border: none;
  cursor: pointer;
  border-left: 3px solid var(--color-accent-light);
  text-align: left;
}

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

.faq-icon {
  width: 20px;
  height: 20px;
  min-width: 20px;
  color: var(--color-primary);
  transition: transform 0.3s ease;
  flex-shrink: 0;
  margin-left: 12px;
}

.faq-item.open .faq-icon {
  transform: rotate(45deg);
}

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

.faq-item.open .faq-answer {
  max-height: 500px;
  opacity: 1;
  padding: 0 24px 20px;
}

.faq-answer p {
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-secondary);
}

/* ── 标签切换 ── */
.tab-bar {
  display: flex;
  gap: 0;
  border-bottom: 2px solid var(--color-accent-light);
  margin-bottom: 32px;
  overflow-x: auto;
}

.tab-item {
  padding: 14px 28px;
  font-size: 15px;
  font-weight: 500;
  color: var(--text-muted);
  background: none;
  border: none;
  border-bottom: 3px solid transparent;
  cursor: pointer;
  white-space: nowrap;
  transition: var(--transition-default);
  margin-bottom: -2px;
}

.tab-item:hover {
  color: var(--text-secondary);
}

.tab-item.active {
  color: var(--color-primary-dark);
  font-weight: 600;
  border-bottom-color: var(--color-primary);
}

/* ── 标签内容面板 ── */
.tab-panel {
  display: none;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.3s ease, transform 0.3s ease;
}

.tab-panel.active {
  display: block;
}

.tab-panel.fade-in {
  opacity: 1;
  transform: translateY(0);
}

/* ── 平台小卡片 ── */
.platform-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 28px 20px;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 16px;
  transition: var(--transition-default);
  cursor: pointer;
}

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

.platform-card svg {
  width: 40px;
  height: 40px;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.platform-card h4 {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 6px;
}

.platform-card p {
  font-size: 13px;
  color: var(--text-muted);
}

/* ── 信息板 ── */
.info-board {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-card);
  padding: 32px;
  position: relative;
  overflow: hidden;
}

.info-board::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--color-accent);
}

.info-board-row {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 16px;
}

.info-board-row:last-child {
  margin-bottom: 0;
}

.info-board-icon {
  width: 48px;
  height: 48px;
  min-width: 48px;
  color: var(--color-primary);
  transition: transform 0.3s ease;
}

.info-board:hover .info-board-icon {
  animation: pulse-green 1s ease-in-out;
}

.info-board-content h4 {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.info-board-content p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ── 提示框 ── */
.tip-box {
  background: var(--bg-secondary);
  border: 1px solid var(--color-accent-medium);
  border-radius: 12px;
  padding: 20px 24px;
}

.tip-box-warning {
  background: var(--warning-bg);
  border-color: var(--warning-border);
}

.tip-box-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-primary-dark);
  margin-bottom: 8px;
}

.tip-box-warning .tip-box-title {
  color: var(--warning-text);
}

.tip-box p {
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-secondary);
}

/* ── 文章卡片 ── */
.article-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-card);
  padding: 28px;
  transition: var(--transition-default);
}

.article-card:hover {
  border-color: var(--card-border-hover);
  box-shadow: var(--card-shadow);
}

.article-card h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.article-card p {
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-secondary);
}

/* ── 版本对比卡片 ── */
.version-card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-card);
  padding: 32px 28px;
  text-align: center;
  transition: var(--transition-default);
  position: relative;
}

.version-card:hover {
  transform: translateY(-5px);
  border-color: var(--card-border-hover);
  box-shadow: var(--card-shadow-hover);
}

.version-card.featured {
  border: 2px solid var(--color-accent);
  background: var(--bg-primary);
}

.version-card .badge {
  position: absolute;
  top: -10px;
  left: 50%;
  transform: translateX(-50%);
}

.version-card h3 {
  font-size: 22px;
  font-weight: 700;
  color: var(--text-primary);
  margin: 12px 0 8px;
}

.version-card .update-cycle {
  font-size: 14px;
  color: var(--color-accent);
  font-weight: 600;
  margin-bottom: 16px;
}

.version-card p {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-secondary);
}

/* ── 页脚 ── */
.footer {
  border-top: 1px solid var(--color-accent-light);
  background: var(--bg-secondary);
  padding: 48px 0 32px;
}

.footer-links {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
}

.footer-links a {
  padding: 6px 16px;
  font-size: 14px;
  color: var(--text-secondary);
  border-radius: var(--radius-input);
  transition: var(--transition-default);
}

.footer-links a:hover {
  background: var(--color-accent-light);
  color: var(--color-primary-dark);
}

.footer-divider {
  width: 40px;
  height: 1px;
  background: var(--color-accent-light);
  margin: 0 auto 20px;
}

.footer-text {
  text-align: center;
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.8;
}

.footer-text p {
  margin-bottom: 4px;
}

/* ── Hero 区域 ── */
.hero {
  background: var(--bg-hero);
  padding: calc(var(--nav-height) + 60px) 0 80px;
  position: relative;
  overflow: hidden;
}

.hero-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.hero-content h1 {
  font-size: 42px;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.2;
  margin-bottom: 20px;
}

.hero-content .highlight {
  color: var(--color-primary);
}

.hero-content p {
  font-size: 17px;
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: 32px;
  max-width: 520px;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-visual {
  display: flex;
  justify-content: center;
  align-items: center;
}

.hero-visual svg {
  width: 100%;
  max-width: 480px;
  height: auto;
  filter: drop-shadow(0 8px 24px rgba(5, 150, 105, 0.15));
}

@media (max-width: 768px) {
  .hero-layout {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .hero-content h1 {
    font-size: 30px;
  }

  .hero-content p {
    font-size: 15px;
  }

  .hero {
    padding: calc(var(--nav-height) + 40px) 0 60px;
  }
}

/* ── CTA 区域 ── */
.cta-section {
  background: var(--bg-hero);
  padding: 60px 0;
  text-align: center;
}

.cta-section h2 {
  font-size: 28px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.cta-section p {
  font-size: 16px;
  color: var(--text-secondary);
  margin-bottom: 28px;
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}