/* ==========================================================================
   任务栏日历 (Taskbar Calendar) 官方网站样式表
   现代卡片 / 毛玻璃 / Fluent 质感 / 深浅色模式
   ========================================================================== */

:root {
  /* 调色板 - 深色（默认） */
  --bg-primary: #0f1117;
  --bg-secondary: #181b24;
  --bg-tertiary: #222634;
  --bg-card: rgba(26, 30, 42, 0.7);
  --bg-card-hover: rgba(34, 40, 56, 0.85);

  --text-primary: #f0f2f8;
  --text-secondary: #9aa1b5;
  --text-muted: #6b7280;

  --accent-primary: #0078d4;
  --accent-gradient: linear-gradient(135deg, #0078d4 0%, #4facfe 100%);
  --accent-glow: rgba(0, 120, 212, 0.35);

  --border-color: rgba(255, 255, 255, 0.08);
  --border-highlight: rgba(255, 255, 255, 0.16);

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.5);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --transition-fast: 0.18s ease;
  --transition-normal: 0.28s ease;

  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Microsoft YaHei", sans-serif;
}

/* 浅色主题覆盖 */
[data-theme="light"] {
  --bg-primary: #f5f7fa;
  --bg-secondary: #ffffff;
  --bg-tertiary: #ebedf2;
  --bg-card: rgba(255, 255, 255, 0.85);
  --bg-card-hover: rgba(255, 255, 255, 0.98);

  --text-primary: #1e2432;
  --text-secondary: #586174;
  --text-muted: #8c96a8;

  --accent-primary: #0067b8;
  --accent-gradient: linear-gradient(135deg, #0067b8 0%, #0099ff 100%);
  --accent-glow: rgba(0, 103, 184, 0.25);

  --border-color: rgba(0, 0, 0, 0.08);
  --border-highlight: rgba(0, 0, 0, 0.14);

  --shadow-sm: 0 2px 6px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 8px 20px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 16px 36px rgba(0, 0, 0, 0.12);
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  background-image: 
    radial-gradient(circle at 15% 15%, var(--accent-glow), transparent 45%),
    radial-gradient(circle at 85% 80%, rgba(79, 172, 254, 0.12), transparent 40%);
  background-attachment: fixed;
}

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

code {
  font-family: "Cascadia Code", Consolas, Monaco, monospace;
  background: var(--bg-tertiary);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.9em;
  color: #4facfe;
}

/* 容器布局 */
.section-container, .nav-container, .hero-container, .footer-container {
  width: 100%;
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 24px;
}

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

/* ==========================================================================
   导航栏 (Navbar)
   ========================================================================== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: rgba(15, 17, 23, 0.75);
  border-bottom: 1px solid var(--border-color);
  transition: background var(--transition-normal);
}

[data-theme="light"] .navbar {
  background: rgba(245, 247, 250, 0.8);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.15rem;
}

.brand-icon {
  width: 28px;
  height: 28px;
}

.badge-version {
  font-size: 0.75rem;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  background: var(--bg-tertiary);
  color: #4facfe;
  border: 1px solid var(--border-highlight);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-links a {
  font-size: 0.95rem;
  color: var(--text-secondary);
  font-weight: 500;
}

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

.nav-link-icon {
  display: flex;
  align-items: center;
  gap: 6px;
}

.btn-theme {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  width: 38px;
  height: 38px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-theme:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-highlight);
}

.sun-icon { display: none; }
.moon-icon { display: block; }

[data-theme="light"] .sun-icon { display: block; }
[data-theme="light"] .moon-icon { display: none; }

/* ==========================================================================
   Hero 首屏
   ========================================================================== */
.hero-section {
  padding: 70px 0 60px;
}

.hero-container {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}

.tagline {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  background: var(--bg-card);
  border: 1px solid var(--border-highlight);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 20px;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  background-color: #10b981;
  border-radius: 50%;
  box-shadow: 0 0 10px #10b981;
}

.hero-title {
  font-size: 2.8rem;
  line-height: 1.25;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
}

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

.hero-subtitle {
  font-size: 1.1rem;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: 36px;
  max-width: 580px;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}

/* 按钮规范 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 24px;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  transition: all var(--transition-fast);
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--accent-gradient);
  color: #ffffff;
  box-shadow: 0 8px 20px var(--accent-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 28px var(--accent-glow);
}

.btn-download {
  padding: 14px 26px;
}

.btn-content {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  text-align: left;
  line-height: 1.25;
}

.btn-content strong {
  font-size: 1.05rem;
}

.btn-content small {
  font-size: 0.75rem;
  opacity: 0.85;
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border-color: var(--border-highlight);
  padding: 14px 22px;
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--text-secondary);
}

.btn-lg {
  padding: 16px 36px;
  font-size: 1.15rem;
}

.system-req {
  font-size: 0.85rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.dot-divider {
  opacity: 0.4;
}

/* Hero 右侧预览图 */
.hero-preview {
  display: flex;
  justify-content: center;
}

.preview-container {
  width: 100%;
  max-width: 400px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 16px;
  box-shadow: var(--shadow-lg);
  backdrop-filter: blur(12px);
}

.preview-tabs {
  display: flex;
  gap: 8px;
  background: var(--bg-tertiary);
  padding: 4px;
  border-radius: var(--radius-sm);
  margin-bottom: 14px;
}

.preview-tab {
  flex: 1;
  padding: 6px 0;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: 6px;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.preview-tab.active {
  background: var(--bg-primary);
  color: var(--text-primary);
  box-shadow: var(--shadow-sm);
}

.preview-image-wrapper {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 420px;
}

.preview-img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-sm);
  transition: opacity 0.25s ease, transform 0.25s ease;
}

.shadow-float {
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.45);
}

.preview-caption {
  text-align: center;
  margin-top: 12px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ==========================================================================
   核心对比条 (Compare Section)
   ========================================================================== */
.compare-section {
  padding: 30px 0 50px;
}

.compare-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.compare-card {
  padding: 28px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  position: relative;
}

.compare-card.good {
  border-color: rgba(0, 120, 212, 0.4);
  background: linear-gradient(180deg, rgba(0, 120, 212, 0.08) 0%, var(--bg-card) 100%);
}

.card-badge {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 700;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  background: var(--bg-tertiary);
  color: var(--text-secondary);
  margin-bottom: 16px;
}

.card-badge.highlight {
  background: var(--accent-primary);
  color: #ffffff;
}

.compare-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.compare-list li {
  font-size: 0.95rem;
  line-height: 1.5;
}

/* ==========================================================================
   特性网格 (Features Section)
   ========================================================================== */
.features-section, .install-section, .faq-section {
  padding: 70px 0;
}

.section-header {
  margin-bottom: 48px;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-secondary);
}

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

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 30px 24px;
  transition: all var(--transition-normal);
  backdrop-filter: blur(8px);
}

.feature-card:hover {
  transform: translateY(-4px);
  background: var(--bg-card-hover);
  border-color: var(--border-highlight);
  box-shadow: var(--shadow-md);
}

.feature-icon {
  font-size: 2rem;
  margin-bottom: 16px;
}

.feature-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.feature-card p {
  font-size: 0.92rem;
  line-height: 1.6;
  color: var(--text-secondary);
}

/* ==========================================================================
   安装引导 (Install Section)
   ========================================================================== */
.steps-wrapper {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 40px;
}

.step-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 32px 24px;
  position: relative;
}

.step-number {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--accent-gradient);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 1.2rem;
  margin-bottom: 18px;
  box-shadow: 0 4px 12px var(--accent-glow);
}

.step-card h3 {
  font-size: 1.15rem;
  margin-bottom: 12px;
}

.step-card p {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.tip-box {
  margin-top: 16px;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  background: var(--bg-tertiary);
  border-left: 3px solid #f59e0b;
  font-size: 0.82rem;
  line-height: 1.5;
  color: var(--text-secondary);
}

.runtime-alert {
  display: flex;
  gap: 16px;
  background: var(--bg-card);
  border: 1px solid var(--border-highlight);
  border-radius: var(--radius-md);
  padding: 24px;
  align-items: flex-start;
}

.alert-icon {
  font-size: 1.8rem;
}

.alert-content h4 {
  font-size: 1.05rem;
  margin-bottom: 6px;
}

.alert-content p {
  font-size: 0.92rem;
  color: var(--text-secondary);
  margin-bottom: 10px;
}

.link-inline {
  color: #4facfe;
  font-weight: 600;
  font-size: 0.92rem;
}

.link-inline:hover {
  text-decoration: underline;
}

/* ==========================================================================
   常见问题 (FAQ Section)
   ========================================================================== */
.faq-accordion {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: border-color var(--transition-fast);
}

.faq-item[open] {
  border-color: var(--border-highlight);
}

.faq-question {
  padding: 18px 24px;
  font-size: 1.02rem;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.faq-question::-webkit-details-marker {
  display: none;
}

.faq-arrow {
  font-size: 1.1rem;
  transition: transform 0.2s ease;
  color: var(--text-muted);
}

.faq-item[open] .faq-arrow {
  transform: rotate(180deg);
}

.faq-answer {
  padding: 0 24px 20px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ==========================================================================
   底部 CTA
   ========================================================================== */
.cta-section {
  padding: 70px 0;
  background: linear-gradient(180deg, transparent 0%, rgba(0, 120, 212, 0.1) 100%);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.cta-title {
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.cta-desc {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin-bottom: 30px;
}

/* ==========================================================================
   页脚 (Footer)
   ========================================================================== */
.footer {
  background: var(--bg-secondary);
  padding: 60px 0 30px;
  margin-top: auto;
}

.footer-container {
  display: grid;
  grid-template-columns: 2fr 1fr 1.5fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.1rem;
  margin-bottom: 12px;
}

.footer-tag {
  font-size: 0.9rem;
  color: var(--text-secondary);
  max-width: 320px;
}

.footer-col h4 {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--text-muted);
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-col a {
  font-size: 0.92rem;
  color: var(--text-secondary);
}

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

.footer-bottom {
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ==========================================================================
   响应式断点适配
   ========================================================================== */
@media (max-width: 960px) {
  .hero-container {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-text {
    display: flex;
    flex-direction: column;
    align-items: center;
  }

  .hero-actions {
    justify-content: center;
  }

  .hero-subtitle {
    margin-left: auto;
    margin-right: auto;
  }

  .system-req {
    justify-content: center;
  }

  .features-grid, .steps-wrapper {
    grid-template-columns: 1fr;
  }

  .compare-grid {
    grid-template-columns: 1fr;
  }

  .footer-container {
    grid-template-columns: 1fr;
    gap: 30px;
  }
}

@media (max-width: 600px) {
  .hero-title {
    font-size: 2.1rem;
  }

  .nav-links a:not(.nav-link-icon) {
    display: none;
  }
}