/* ===== BettaBasics — clean, beginner-friendly aquarium niche site ===== */

:root {
  --ink: #1f2a22;
  --muted: #5c6b60;
  --brand: #2e7d67;
  --brand-dark: #1f5c4b;
  --accent: #d98e2b;
  --bg: #f7f6f1;
  --card: #ffffff;
  --line: #e3e2d9;
  --soft: #eef3ef;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Roboto, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
}

a { color: var(--brand-dark); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: 820px; margin: 0 auto; padding: 0 20px; }

/* Header */
.site-header {
  background: var(--brand);
  color: #fff;
  padding: 18px 0;
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 10px; }
.brand { font-size: 22px; font-weight: 700; color: #fff; }
.brand:hover { text-decoration: none; }
.brand small { display: block; font-size: 12px; font-weight: 400; opacity: .85; }
.main-nav { display: flex; gap: 18px; flex-wrap: wrap; }
.main-nav a { color: #fff; font-size: 15px; opacity: .95; }
.main-nav a:hover { text-decoration: underline; }

/* Hero */
.hero { background: var(--brand-dark); color: #fff; padding: 44px 0; }
.hero h1 { font-size: 30px; margin: 0 0 10px; line-height: 1.3; }
.hero p { font-size: 17px; opacity: .9; margin: 0 0 6px; }
.hero .tagline { font-size: 14px; opacity: .75; }

/* Sections */
.section { padding: 34px 0; }
.section h2 { font-size: 24px; margin: 0 0 6px; color: var(--ink); }
.section .sub { color: var(--muted); margin: 0 0 22px; }

/* Cards */
.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 16px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 18px; }
.card h3 { margin: 0 0 6px; font-size: 17px; }
.card p { margin: 0; font-size: 14px; color: var(--muted); }
.card .go { margin-top: 10px; font-size: 13px; font-weight: 600; color: var(--brand-dark); }

/* Article layout */
.article { max-width: 760px; margin: 0 auto; padding: 34px 20px 60px; }
.article h1 { font-size: 30px; line-height: 1.3; margin: 0 0 8px; }
.article .meta { color: var(--muted); font-size: 14px; margin: 0 0 24px; }
.article h2 { font-size: 24px; margin: 34px 0 10px; border-bottom: 1px solid var(--line); padding-bottom: 6px; }
.article h3 { font-size: 19px; margin: 26px 0 8px; }
.article p { font-size: 16px; }
.article ul, .article ol { font-size: 16px; }
.article blockquote { border-left: 4px solid var(--accent); margin: 18px 0; padding: 4px 16px; background: var(--soft); }
.article table { width: 100%; border-collapse: collapse; margin: 16px 0; font-size: 15px; }
.article th, .article td { border: 1px solid var(--line); padding: 9px 10px; text-align: left; }
.article th { background: var(--soft); }
.article img { max-width: 100%; border-radius: 8px; }
.article .callout { background: var(--soft); border-left: 4px solid var(--brand); padding: 12px 16px; border-radius: 0 8px 8px 0; margin: 18px 0; }
.article .toc { background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 16px 22px; margin: 20px 0; }
.article .toc h4 { margin: 0 0 8px; }
.article .toc ol { margin: 0; }
.article .toc a { color: var(--brand-dark); }
.pager { margin-top: 40px; display: flex; justify-content: space-between; gap: 12px; }
.pager a { background: var(--card); border: 1px solid var(--line); padding: 8px 14px; border-radius: 8px; font-size: 14px; }

/* Site footer */
.site-footer { background: var(--ink); color: #cfd8cf; padding: 28px 0; font-size: 14px; }
.site-footer .container { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; }
.site-footer a { color: #cfd8cf; }

/* Table overflow guard (wrap tables in <div class="table-wrap"> when needed) */
.table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }

/* Mobile */
@media (max-width: 640px) {
  .container { padding: 0 16px; }
  .article { padding: 24px 16px 48px; }
  .hero h1, .article h1 { font-size: 24px; }
  .article h2 { font-size: 20px; }
  .article p, .article li { font-size: 16px; }
  .article table { display: block; overflow-x: auto; white-space: nowrap; }
  .main-nav { gap: 12px; }
  .card-grid { grid-template-columns: 1fr; }
}