/* ============================================
   威士忌 - 案例展示风格样式表
   主色调: #00bcd4 (青色)
   布局: 分屏布局 (Split Screen)
   ============================================ */

/* CSS 变量定义 */
:root {
  --accent-color: #00bcd4;
  --accent-dark: #0097a7;
  --accent-light: #b2ebf2;
  --text-primary: #212121;
  --text-secondary: #757575;
  --text-light: #ffffff;
  --bg-primary: #ffffff;
  --bg-secondary: #f5f5f5;
  --bg-dark: #263238;
  --border-color: #e0e0e0;
  --shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  --radius: 4px;
  --max-width: 1200px;
  --header-height: 64px;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

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

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

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

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

ul, ol {
  list-style: none;
}

/* ============================================
   页头 (Header)
   ============================================ */
.header {
  background-color: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
}

.logo span {
  color: var(--accent-color);
}

.nav {
  display: flex;
  gap: 32px;
}

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

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

/* ============================================
   分屏布局 (Split Screen)
   ============================================ */
.split-screen {
  display: grid;
  grid-template-columns: 1fr 1fr;
  min-height: calc(100vh - var(--header-height) - 300px);
}

.split-panel {
  padding: 64px 48px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.split-panel-left {
  background-color: var(--bg-primary);
}

.split-panel-right {
  background-color: var(--bg-secondary);
}

.split-panel h1 {
  font-size: 2.5rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 24px;
  color: var(--text-primary);
}

.split-panel h2 {
  font-size: 2rem;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--text-primary);
}

.split-panel .subtitle {
  font-size: 1.125rem;
  color: var(--accent-color);
  font-weight: 600;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.split-panel p {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 24px;
}

.cta-button {
  display: inline-block;
  padding: 14px 32px;
  background-color: var(--accent-color);
  color: var(--text-light);
  font-weight: 600;
  border-radius: var(--radius);
  transition: background-color 0.2s;
  align-self: flex-start;
}

.cta-button:hover {
  background-color: var(--accent-dark);
  color: var(--text-light);
}

.cta-button-outline {
  background-color: transparent;
  border: 2px solid var(--accent-color);
  color: var(--accent-color);
}

.cta-button-outline:hover {
  background-color: var(--accent-color);
  color: var(--text-light);
}

/* 案例封面 */
.case-hero {
  position: relative;
  background: linear-gradient(135deg, var(--bg-dark) 0%, #37474f 100%);
  color: var(--text-light);
  padding: 80px 48px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.case-hero h1 {
  color: var(--text-light);
  font-size: 3rem;
  margin-bottom: 16px;
}

.case-hero .subtitle {
  color: var(--accent-light);
}

.case-hero p {
  color: rgba(255, 255, 255, 0.8);
}

/* ============================================
   面包屑导航 (Breadcrumb)
   ============================================ */
.breadcrumb {
  background-color: var(--bg-secondary);
  padding: 16px 24px;
  border-bottom: 1px solid var(--border-color);
}

.breadcrumb-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

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

.breadcrumb a:hover {
  color: var(--accent-color);
}

.breadcrumb span {
  margin: 0 8px;
  color: var(--border-color);
}

.breadcrumb strong {
  color: var(--text-primary);
  font-weight: 500;
}

/* ============================================
   三栏内容区 (Triple Column)
   ============================================ */
.triple-section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 64px 24px;
}

.triple-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.triple-column h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--accent-color);
  color: var(--text-primary);
}

.triple-column ul {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.triple-column li {
  position: relative;
  padding-left: 16px;
}

.triple-column li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--accent-color);
}

.triple-column a {
  color: var(--text-secondary);
  display: block;
  padding: 4px 0;
}

.triple-column a:hover {
  color: var(--accent-color);
}

/* ============================================
   分类列表 (Category List)
   ============================================ */
.category-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  min-height: 500px;
}

.category-panel {
  padding: 48px;
  border-right: 1px solid var(--border-color);
}

.category-panel:last-child {
  border-right: none;
}

.category-panel h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 24px;
  color: var(--text-primary);
}

.category-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.category-item {
  padding: 16px;
  background-color: var(--bg-secondary);
  border-radius: var(--radius);
  border-left: 4px solid var(--accent-color);
  transition: box-shadow 0.2s;
}

.category-item:hover {
  box-shadow: var(--shadow);
}

.category-item h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 4px;
  color: var(--text-primary);
}

.category-item p {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.view-all {
  display: inline-block;
  margin-top: 24px;
  padding: 10px 24px;
  background-color: var(--accent-color);
  color: var(--text-light);
  font-weight: 500;
  border-radius: var(--radius);
  font-size: 0.875rem;
}

.view-all:hover {
  background-color: var(--accent-dark);
  color: var(--text-light);
}

/* ============================================
   文章详情 (Article Detail)
   ============================================ */
.article-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  min-height: calc(100vh - var(--header-height) - 200px);
}

.article-panel {
  padding: 48px;
  overflow-y: auto;
}

.article-panel-left {
  background-color: var(--bg-primary);
  border-right: 1px solid var(--border-color);
}

.article-panel-right {
  background-color: var(--bg-secondary);
}

.article-header {
  margin-bottom: 32px;
}

.article-header .category-tag {
  display: inline-block;
  padding: 6px 16px;
  background-color: var(--accent-light);
  color: var(--accent-dark);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  border-radius: var(--radius);
  margin-bottom: 16px;
}

.article-header h1 {
  font-size: 2rem;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.article-meta {
  display: flex;
  gap: 24px;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.article-content {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-primary);
}

.article-content h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin: 32px 0 16px;
  color: var(--text-primary);
}

.article-content h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 24px 0 12px;
  color: var(--text-primary);
}

.article-content p {
  margin-bottom: 16px;
  color: var(--text-secondary);
}

.article-content ul,
.article-content ol {
  margin-bottom: 16px;
  padding-left: 24px;
}

.article-content ul li {
  list-style: disc;
  margin-bottom: 8px;
  color: var(--text-secondary);
}

.article-content ol li {
  list-style: decimal;
  margin-bottom: 8px;
  color: var(--text-secondary);
}

/* ============================================
   推荐文章区 (Recommended Section)
   ============================================ */
.recommended-section {
  background-color: var(--bg-secondary);
  padding: 48px 24px;
}

.recommended-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.recommended-header {
  margin-bottom: 24px;
}

.recommended-header h3 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-primary);
}

.related-list {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 32px;
}

.related-item {
  padding: 12px 20px;
  background-color: var(--bg-primary);
  border-radius: var(--radius);
  border: 1px solid var(--border-color);
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: all 0.2s;
}

.related-item:hover {
  border-color: var(--accent-color);
  color: var(--accent-color);
}

.dual-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}

.dual-column h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-primary);
}

.dual-column ul {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.dual-column li {
  position: relative;
  padding-left: 16px;
}

.dual-column li::before {
  content: "•";
  position: absolute;
  left: 0;
  color: var(--accent-color);
}

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

.dual-column a:hover {
  color: var(--accent-color);
}

/* ============================================
   404 页面
   ============================================ */
.error-page {
  min-height: calc(100vh - var(--header-height) - 200px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 48px 24px;
  text-align: center;
}

.error-content h1 {
  font-size: 8rem;
  font-weight: 700;
  color: var(--accent-color);
  line-height: 1;
  margin-bottom: 16px;
}

.error-content h2 {
  font-size: 2rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.error-content p {
  font-size: 1.125rem;
  color: var(--text-secondary);
  margin-bottom: 32px;
}

/* ============================================
   页脚 (Footer)
   ============================================ */
.footer {
  background-color: var(--bg-dark);
  color: var(--text-light);
  padding: 48px 24px 24px;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand h3 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.footer-brand h3 span {
  color: var(--accent-color);
}

.footer-brand p {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.875rem;
  line-height: 1.8;
}

.footer-column h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 20px;
  color: var(--text-light);
}

.footer-column ul {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-column a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.875rem;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 24px;
  text-align: center;
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.5);
}

/* ============================================
   响应式设计
   ============================================ */
@media (max-width: 1024px) {
  .split-screen,
  .category-split,
  .article-split {
    grid-template-columns: 1fr;
  }

  .split-panel,
  .category-panel,
  .article-panel {
    padding: 48px 32px;
  }

  .article-panel-left {
    border-right: none;
    border-bottom: 1px solid var(--border-color);
  }

  .category-panel {
    border-right: none;
    border-bottom: 1px solid var(--border-color);
  }

  .category-panel:last-child {
    border-bottom: none;
  }

  .triple-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .header-inner {
    padding: 0 16px;
  }

  .nav {
    gap: 16px;
  }

  .nav a {
    font-size: 0.875rem;
  }

  .split-panel h1 {
    font-size: 2rem;
  }

  .split-panel h2 {
    font-size: 1.5rem;
  }

  .case-hero h1 {
    font-size: 2rem;
  }

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

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

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

  .error-content h1 {
    font-size: 5rem;
  }
}

@media (max-width: 480px) {
  .split-panel,
  .category-panel,
  .article-panel {
    padding: 32px 20px;
  }

  .triple-section {
    padding: 48px 16px;
  }

  .cta-button {
    width: 100%;
    text-align: center;
  }
}