/* 第五版：全新设计语言
   - 顶部窄条信息栏 + 下方“三栏杂志式布局”
   - 首页主区域为左侧导引栏 + 中间长文 + 右侧摘要
   - 少量柔和色块，无大 hero 卡片
*/

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

html {
  font-size: 16px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: #fdf6ec;
  color: #202124;
  line-height: 1.8;
}

a {
  color: #0d7b72;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.topbar {
  background: #111827;
  color: #e5e7eb;
  font-size: 0.82rem;
  padding: 0.3rem 1.6rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.topbar span {
  opacity: 0.9;
}

.topbar a {
  color: #a5f3fc;
}

.shell {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1.3rem 1.3rem 2.2rem;
}

.shell-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 1.1rem;
}

.site-title {
  font-size: 1.6rem;
  font-weight: 700;
}

.site-sub {
  font-size: 0.88rem;
  color: #5f6368;
  margin-top: 0.3rem;
}

.site-nav {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
  font-size: 0.9rem;
}

.site-nav a {
  padding: 0.1rem 0;
  border-bottom: 2px solid transparent;
  color: #374151;
}

.site-nav a.active {
  border-color: #0d9488;
  color: #0d9488;
}

.site-nav a:hover {
  border-color: #64748b;
}

/* 三栏杂志式布局 */
.layout {
  display: grid;
  grid-template-columns: 220px minmax(0, 1.7fr) minmax(0, 1fr);
  gap: 1.4rem;
}

.col-left {
  font-size: 0.86rem;
}

.col-left .block + .block {
  margin-top: 1.1rem;
}

.block-title {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: #6b7280;
  margin-bottom: 0.4rem;
}

.toc {
  list-style: none;
}

.toc li + li {
  margin-top: 0.3rem;
}

.toc a {
  color: #374151;
}

.toc a:hover {
  color: #0f766e;
}

.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.tag {
  font-size: 0.76rem;
  padding: 0.08rem 0.4rem;
  border-radius: 999px;
  background: #fefce8;
  border: 1px solid #e5e7eb;
  color: #92400e;
}

.col-main {
  background: #fffdf8;
  border-radius: 0.9rem;
  border: 1px solid #f3e5d7;
  padding: 1.2rem 1.3rem;
}

.main-heading {
  font-size: 1.4rem;
  margin-bottom: 0.4rem;
}

.main-meta {
  font-size: 0.82rem;
  color: #78716c;
  margin-bottom: 0.9rem;
}

.main-section {
  margin-bottom: 1.3rem;
}

.main-section h2 {
  font-size: 1.05rem;
  margin-bottom: 0.4rem;
  border-left: 3px solid #0d9488;
  padding-left: 0.5rem;
}

.main-section p {
  font-size: 0.95rem;
  margin-bottom: 0.7rem;
  text-indent: 2em;
}

.col-right {
  font-size: 0.86rem;
}

.aside-card {
  background: #ffffff;
  border-radius: 0.75rem;
  padding: 0.9rem 1rem;
  border: 1px solid #e5e7eb;
}

.aside-card + .aside-card {
  margin-top: 0.9rem;
}

.aside-card h3 {
  font-size: 0.9rem;
  margin-bottom: 0.4rem;
}

.aside-list {
  list-style: none;
}

.aside-list li + li {
  margin-top: 0.3rem;
}

.aside-list a {
  color: #374151;
}

.aside-list a:hover {
  color: #0d9488;
}

.footer {
  margin-top: 1.6rem;
  font-size: 0.78rem;
  color: #6b7280;
  border-top: 1px solid #e5e7eb;
  padding-top: 0.8rem;
}

/* 列表页 */
.list-main {
  background: #ffffff;
  border-radius: 0.9rem;
  border: 1px solid #e5e7eb;
  padding: 1.1rem 1.2rem;
}

.list-title {
  font-size: 1.25rem;
  margin-bottom: 0.4rem;
}

.list-intro {
  font-size: 0.9rem;
  color: #4b5563;
  margin-bottom: 0.9rem;
}

.article-list {
  list-style: none;
}

.article-item {
  padding: 0.6rem 0;
  border-bottom: 1px solid #f1f5f9;
  display: grid;
  grid-template-columns: 120px minmax(0, 1fr);
  gap: 0.8rem;
}

.article-thumb img {
  width: 100%;
  height: 80px;
  object-fit: cover;
  border-radius: 0.6rem;
}

.article-meta {
  font-size: 0.78rem;
  color: #6b7280;
  margin-bottom: 0.1rem;
}

.article-title {
  font-size: 0.98rem;
  margin-bottom: 0.1rem;
}

.article-title a {
  color: #111827;
}

.article-title a:hover {
  color: #0f766e;
}

.article-desc {
  font-size: 0.86rem;
  color: #4b5563;
}

/* 文章页 */
.article-page {
  background: #ffffff;
  border-radius: 0.9rem;
  border: 1px solid #e5e7eb;
  padding: 1.1rem 1.2rem 1.3rem;
}

.article-page h1 {
  font-size: 1.4rem;
  margin-bottom: 0.4rem;
}

.article-meta-line {
  font-size: 0.8rem;
  color: #78716c;
  margin-bottom: 0.7rem;
}

.article-cover {
  margin-bottom: 0.9rem;
}

.article-cover img {
  width: 100%;
  border-radius: 0.7rem;
}

.article-body p {
  font-size: 0.95rem;
  margin-bottom: 0.8rem;
  text-indent: 2em;
}

.article-body h2 {
  font-size: 1.05rem;
  margin: 0.8rem 0 0.4rem;
  border-left: 3px solid #0f766e;
  padding-left: 0.45rem;
}

/* 响应式 */
@media (max-width: 960px) {
  .layout {
    grid-template-columns: minmax(0, 1.8fr) minmax(0, 1.2fr);
  }
  .col-left {
    display: none;
  }
}

@media (max-width: 720px) {
  html {
    font-size: 15px;
  }
  .shell {
    padding: 1rem 1rem 2rem;
  }
  .shell-header {
    flex-direction: column;
    gap: 0.5rem;
  }
  .site-nav {
    gap: 0.6rem;
  }
  .layout {
    grid-template-columns: minmax(0, 1fr);
  }
  .col-right {
    margin-top: 1rem;
  }
  .article-item {
    grid-template-columns: minmax(0, 1fr);
  }
  .article-thumb img {
    height: 150px;
  }
}