:root { --bg: #f3f5f8; --card: #fff; --text: #1d1f23; --muted: #6b7280; --accent: #2b6cb0; }
* { box-sizing: border-box; }
html, body { height: 100%; }
body { margin: 0; font-family: Arial, sans-serif; background: #f3f5f8; color: #1d1f23; }
.container { width: min(1100px, 90%); margin: 0 auto; }
.site-header { background: linear-gradient(135deg, #2b6cb0 0%, #4f8bd6 60%, #6bd8ff 100%); color: white; padding: 14px 0; }
.header-inner { display:flex; align-items:center; justify-content: space-between; gap: 12px; padding: 0 4px; }
.logo { display:flex; align-items:center; gap:8px; font-weight:700; font-size:1.4rem; text-transform: uppercase; letter-spacing:.5px; }
.logo-mark { width: 28px; height: 28px; border-radius:6px; background:white; display:inline-block; }
.main-nav ul { list-style:none; display:flex; gap:20px; padding:0; margin:0; }
.main-nav a { color:white; text-decoration:none; opacity:.95; }
.search-form { display:flex; align-items:center; }
.search-form .search-input { padding:8px 12px; border-radius: 50px; border: none; outline: none; width: 170px; }

.hero { padding: 28px 0; text-align:center; background:white; border-bottom: 1px solid #e5e7eb; }
.hero h1 { margin:0 0 8px; font-size: 2rem; }
.hero p { margin:0; color:#555; }

.grid { display: grid; gap: 20px; }
.grid.two-col { grid-template-columns: 1fr 320px; align-items: start; }

.card { background:white; border-radius: 8px; padding: 16px; box-shadow: 0 1px 2px rgba(0,0,0,.04); }
.section-header { display:flex; justify-content:space-between; align-items:center; }
.topic-list { list-style:none; padding:0; margin:0; }
.topic-item { display:flex; align-items:flex-start; padding:8px 0; border-bottom:1px solid #eee; }
.topic-icon { font-size:1.4rem; margin-right:10px; }
.topic-content a { font-weight:600; color:#2b2b2b; text-decoration:none; }
.topic-content .meta { font-size:.85rem; color:#6b7280; margin-top:2px; }

.category-list { padding-left: 1em; margin:0; }
.category-list li { padding:6px 0; border-bottom:1px dashed #eee; }

footer { padding:20px 0; color:#6b7280; font-size:.9rem; }

@media (max-width: 900px) {
  .grid.two-col { grid-template-columns: 1fr; }
  .search-form { display:none; } 
  .header-inner { flex-wrap: wrap; gap: 8px; }
  .logo { font-size: 1.2rem; }
}