/* Business Insider 风格 - 全新样式 */
* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: 'Helvetica Neue', Helvetica, Arial, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif; color: #111; background: #fff; line-height: 1.5; -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; transition: color .15s; }
a:hover { color: #E00000; }
img { display: block; max-width: 100%; height: auto; border: 0; }
ul, ol { list-style: none; }
h1, h2, h3, h4 { font-weight: 800; color: #111; line-height: 1.25; }

/* 顶部导航条 */
.bi-topbar { background: #111; color: #fff; border-bottom: 3px solid #E00000; }
.bi-topbar-inner { max-width: 1200px; margin: 0 auto; display: flex; align-items: center; padding: 14px 24px; }
.bi-logo { font-size: 28px; font-weight: 900; color: #fff; letter-spacing: -1px; }
.bi-logo span { color: #E00000; }
.bi-tag { background: #E00000; color: #fff; font-size: 10px; padding: 2px 6px; margin-left: 8px; vertical-align: super; font-weight: 700; letter-spacing: .5px; }
.bi-nav { display: flex; flex: 1; margin-left: 48px; flex-wrap: wrap; }
.bi-nav a { color: #fff; padding: 0 14px; font-size: 13px; font-weight: 700; text-transform: uppercase; letter-spacing: .5px; line-height: 36px; }
.bi-nav a:hover { color: #E00000; }
.bi-nav .bi-nav-active { color: #E00000; }
.bi-search { color: #fff; font-size: 14px; }
.bi-search input { background: #222; border: none; color: #fff; padding: 6px 10px; width: 160px; font-size: 13px; outline: none; }
.bi-search input::placeholder { color: #888; }
.bi-search button { background: #E00000; color: #fff; border: none; padding: 6px 12px; font-size: 13px; cursor: pointer; font-weight: 700; }

/* 二级栏目标签条 */
.bi-subnav { background: #f5f5f5; border-bottom: 1px solid #e5e5e5; }
.bi-subnav-inner { max-width: 1200px; margin: 0 auto; padding: 10px 24px; display: flex; gap: 20px; font-size: 13px; overflow-x: auto; white-space: nowrap; }
.bi-subnav a { color: #555; font-weight: 600; }
.bi-subnav a:hover { color: #E00000; }
.bi-subnav .bi-sub-active { color: #E00000; }

/* 面包屑 */
.bi-crumb { max-width: 1200px; margin: 16px auto 0; padding: 0 24px; font-size: 12px; color: #888; }
.bi-crumb a { color: #555; }
.bi-crumb a:hover { color: #E00000; }
.bi-crumb-sep { margin: 0 6px; color: #ccc; }

/* 容器 */
.bi-container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* 头条区 */
.bi-hero { display: grid; grid-template-columns: 2fr 1fr; gap: 24px; margin-top: 16px; }
.bi-hero-main { position: relative; }
.bi-hero-main a { display: block; }
.bi-hero-main img { width: 100%; aspect-ratio: 16/9; object-fit: cover; }
.bi-hero-main h1 { font-size: 32px; line-height: 1.2; margin: 12px 0 6px; }
.bi-hero-main h1 a:hover { color: #E00000; }
.bi-hero-side { display: flex; flex-direction: column; }
.bi-hero-side-item { padding: 12px 0; border-bottom: 1px solid #eee; }
.bi-hero-side-item:first-child { padding-top: 0; }
.bi-hero-side-item h3 { font-size: 16px; line-height: 1.3; margin: 0 0 4px; }
.bi-hero-side-item .bi-meta { font-size: 12px; color: #888; }

/* 栏目分区 */
.bi-section { margin-top: 40px; }
.bi-section-head { display: flex; align-items: baseline; justify-content: space-between; border-bottom: 3px solid #111; padding-bottom: 8px; margin-bottom: 16px; }
.bi-section-head h2 { font-size: 22px; text-transform: uppercase; letter-spacing: .5px; }
.bi-section-head h2 span { color: #E00000; }
.bi-section-head .bi-more { font-size: 12px; color: #888; font-weight: 600; }
.bi-section-head .bi-more:hover { color: #E00000; }

/* 三列网格 */
.bi-grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.bi-grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.bi-grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }

/* 卡片 */
.bi-card { display: block; }
.bi-card .bi-card-img { width: 100%; aspect-ratio: 16/9; object-fit: cover; background: #f5f5f5; }
.bi-card .bi-cat { display: inline-block; background: #E00000; color: #fff; font-size: 10px; padding: 2px 6px; text-transform: uppercase; font-weight: 700; letter-spacing: .5px; margin-top: 10px; }
.bi-card h3 { font-size: 16px; line-height: 1.3; margin: 8px 0 6px; }
.bi-card .bi-meta { font-size: 12px; color: #888; }
.bi-card p { font-size: 13px; color: #555; line-height: 1.5; margin-top: 6px; display: -webkit-box; -webkit-line-clamp: 4; -webkit-box-orient: vertical; overflow: hidden; }

/* 横排卡片(列表式) */
.bi-row { display: flex; gap: 16px; padding: 16px 0; border-bottom: 1px solid #eee; }
.bi-row img { width: 220px; height: 130px; object-fit: cover; flex-shrink: 0; background: #f5f5f5; }
.bi-row-content { flex: 1; min-width: 0; }
.bi-row-content h3 { font-size: 18px; line-height: 1.3; margin: 0 0 6px; }
.bi-row-content .bi-cat { font-size: 11px; color: #E00000; font-weight: 700; text-transform: uppercase; }
.bi-row-content p { font-size: 13px; color: #555; line-height: 1.5; margin: 6px 0; display: -webkit-box; -webkit-line-clamp: 4; -webkit-box-orient: vertical; overflow: hidden; }
.bi-row-content .bi-meta { font-size: 12px; color: #888; }

/* 双栏(列表+侧栏) */
.bi-cols { display: grid; grid-template-columns: 2fr 1fr; gap: 32px; }

/* 侧栏 */
.bi-side { padding-left: 20px; border-left: 1px solid #eee; }
.bi-side h3.bi-side-title { font-size: 14px; text-transform: uppercase; border-bottom: 2px solid #111; padding-bottom: 6px; margin-bottom: 14px; letter-spacing: 1px; }
.bi-side-list li { padding: 10px 0; border-bottom: 1px solid #f0f0f0; }
.bi-side-list li a { font-size: 14px; line-height: 1.4; font-weight: 600; }
.bi-side-list .bi-meta { font-size: 12px; color: #888; display: block; margin-top: 4px; }

/* 文章页 */
.bi-article { display: grid; grid-template-columns: 2fr 1fr; gap: 32px; margin-top: 20px; }
.bi-article-main h1 { font-size: 36px; line-height: 1.2; margin: 8px 0 16px; }
.bi-article-meta { color: #666; font-size: 13px; margin-bottom: 20px; padding-bottom: 16px; border-bottom: 1px solid #eee; }
.bi-article-meta span { margin-right: 16px; }
.bi-article-body { font-size: 16px; line-height: 1.8; color: #222; }
.bi-article-body p { margin: 16px 0; }
.bi-article-body img { max-width: 100%; height: auto; margin: 12px 0; }
.bi-article-body h2, .bi-article-body h3 { margin: 24px 0 12px; }

/* 分页 */
.bi-page { padding: 24px 0; text-align: center; }
.bi-page ul { display: inline-flex; gap: 6px; flex-wrap: wrap; justify-content: center; }
.bi-page li a, .bi-page li span { display: inline-block; padding: 6px 12px; border: 1px solid #ddd; font-size: 13px; color: #333; }
.bi-page li a:hover { background: #111; color: #fff; border-color: #111; }
.bi-page li.active span { background: #E00000; color: #fff; border-color: #E00000; }

/* 页脚 */
.bi-footer { background: #111; color: #aaa; padding: 40px 24px 24px; margin-top: 60px; }
.bi-footer-inner { max-width: 1200px; margin: 0 auto; }
.bi-footer-grid { display: grid; grid-template-columns: 2fr 1fr; gap: 32px; margin-bottom: 24px; }
.bi-footer h4 { color: #fff; font-size: 13px; text-transform: uppercase; margin-bottom: 12px; letter-spacing: 1px; }
.bi-footer ul li { padding: 4px 0; }
.bi-footer ul li a { color: #aaa; font-size: 13px; }
.bi-footer ul li a:hover { color: #fff; }
.bi-footer-links { text-align: center; font-size: 13px; color: #888; line-height: 2.2; padding-bottom: 16px; }
.bi-footer-links a { color: #aaa; margin: 0 4px; }
.bi-footer-links a:hover { color: #fff; }
.bi-footer-bottom { border-top: 1px solid #333; padding-top: 16px; text-align: center; font-size: 12px; color: #888; }
.bi-footer-bottom a { color: #aaa; margin: 0 8px; }
.bi-footer-bottom a:hover { color: #fff; }

/* 响应式 */
@media (max-width: 900px) {
    .bi-hero, .bi-cols, .bi-article { grid-template-columns: 1fr; }
    .bi-grid-3, .bi-grid-4 { grid-template-columns: 1fr 1fr; }
    .bi-side { padding-left: 0; border-left: none; border-top: 1px solid #eee; margin-top: 24px; padding-top: 20px; }
    .bi-row img { width: 140px; height: 90px; }
    .bi-footer-grid { grid-template-columns: 1fr 1fr; }
    .bi-nav { display: none; }
    .bi-hero-main h1 { font-size: 24px; }
}
@media (max-width: 600px) {
    .bi-grid-3, .bi-grid-4, .bi-grid-2 { grid-template-columns: 1fr; }
    .bi-row img { width: 100px; height: 70px; }
}