/* SumKit — shared design system. One light theme, one accent color. */
:root {
  --accent: #2563eb;
  --accent-dark: #1d4ed8;
  --accent-light: #eff6ff;
  --text: #1f2937;
  --text-muted: #6b7280;
  --border: #e5e7eb;
  --bg: #ffffff;
  --bg-soft: #f9fafb;
  --radius: 10px;
  --max-width: 1080px;
  --shadow: 0 1px 3px rgba(0,0,0,.08), 0 1px 2px rgba(0,0,0,.05);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  font-size: 17px;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3 { line-height: 1.25; margin: 0 0 .5em; }
h1 { font-size: 2rem; }
h2 { font-size: 1.4rem; margin-top: 1.8em; }
h3 { font-size: 1.1rem; margin-top: 1.2em; }
p { margin: 0 0 1em; }
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 20px; }

/* Header */
.site-header { background: var(--bg); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 50; }
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 14px 20px; max-width: var(--max-width); margin: 0 auto; }
.logo { font-size: 1.35rem; font-weight: 800; color: var(--text); letter-spacing: -0.02em; }
.logo span { color: var(--accent); }
.logo:hover { text-decoration: none; }
.main-nav { display: flex; gap: 4px; flex-wrap: wrap; }
.main-nav a { color: var(--text); font-weight: 600; font-size: .95rem; padding: 8px 12px; border-radius: 8px; }
.main-nav a:hover, .main-nav a.active { background: var(--accent-light); color: var(--accent-dark); text-decoration: none; }
.nav-toggle { display: none; background: none; border: 1px solid var(--border); border-radius: 8px; padding: 8px 12px; font-size: 1.1rem; cursor: pointer; }

/* Hero */
.hero { background: var(--accent-light); border-bottom: 1px solid var(--border); padding: 48px 0 40px; text-align: center; }
.hero h1 { font-size: 2.3rem; margin-bottom: .3em; }
.hero p { color: var(--text-muted); font-size: 1.1rem; max-width: 640px; margin: 0 auto 1.4em; }
.search-box { max-width: 520px; margin: 0 auto; }
.search-box input { width: 100%; padding: 14px 18px; font-size: 1rem; border: 1px solid var(--border); border-radius: 999px; box-shadow: var(--shadow); outline: none; }
.search-box input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(37,99,235,.15); }

/* Category sections + tool cards */
.category-section { padding: 36px 0 8px; }
.category-section h2 { margin-top: 0; }
.category-desc { color: var(--text-muted); margin-top: -.3em; }
.tool-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 16px; margin-top: 16px; }
.tool-card { display: block; background: var(--bg); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow); color: var(--text); transition: transform .12s ease, box-shadow .12s ease; }
.tool-card:hover { text-decoration: none; transform: translateY(-2px); box-shadow: 0 4px 12px rgba(0,0,0,.1); }
.tool-card h3 { margin: 0 0 .35em; color: var(--accent-dark); font-size: 1.05rem; }
.tool-card p { margin: 0; color: var(--text-muted); font-size: .92rem; }
.tool-icon { font-size: 1.6rem; display: block; margin-bottom: .4em; }

/* Tool pages */
.breadcrumb { font-size: .9rem; color: var(--text-muted); margin: 20px 0 8px; }
.breadcrumb a { color: var(--text-muted); }
.page-intro { color: var(--text-muted); font-size: 1.05rem; max-width: 760px; }
.tool-box { background: var(--bg-soft); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; margin: 24px 0; max-width: 760px; }
.form-row { display: flex; gap: 16px; flex-wrap: wrap; }
.form-group { flex: 1 1 200px; margin-bottom: 16px; }
.form-group label { display: block; font-weight: 600; font-size: .92rem; margin-bottom: 6px; }
.form-group input, .form-group select, .form-group textarea {
  width: 100%; padding: 11px 12px; font-size: 1rem; border: 1px solid var(--border);
  border-radius: 8px; background: #fff; font-family: inherit;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(37,99,235,.15); }
.form-hint { font-size: .82rem; color: var(--text-muted); margin-top: 4px; }
.btn { display: inline-block; background: var(--accent); color: #fff; border: none; border-radius: 8px; padding: 12px 26px; font-size: 1rem; font-weight: 700; cursor: pointer; }
.btn:hover { background: var(--accent-dark); }
.btn-secondary { background: #fff; color: var(--accent-dark); border: 1px solid var(--accent); }
.btn-secondary:hover { background: var(--accent-light); }
.result-box { background: #fff; border: 2px solid var(--accent); border-radius: var(--radius); padding: 20px 24px; margin-top: 20px; display: none; }
.result-box.visible { display: block; }
.result-main { font-size: 1.9rem; font-weight: 800; color: var(--accent-dark); margin: 4px 0 12px; }
.result-label { font-size: .85rem; text-transform: uppercase; letter-spacing: .04em; color: var(--text-muted); font-weight: 700; }
.result-table { width: 100%; border-collapse: collapse; margin-top: 12px; font-size: .95rem; }
.result-table td { padding: 8px 4px; border-top: 1px solid var(--border); }
.result-table td:last-child { text-align: right; font-weight: 700; }
.error-msg { color: #b91c1c; font-size: .92rem; font-weight: 600; margin-top: 10px; display: none; }
.error-msg.visible { display: block; }
.note-box { background: #fffbeb; border: 1px solid #fde68a; border-radius: var(--radius); padding: 14px 18px; font-size: .92rem; margin: 20px 0; }
.content-section { max-width: 760px; }
.faq-item { border-bottom: 1px solid var(--border); padding: 12px 0; }
.faq-item h3 { margin: 0 0 .3em; font-size: 1rem; }
.faq-item p { margin: 0; color: var(--text-muted); }
.related-tools { background: var(--bg-soft); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px 24px; margin: 28px 0; max-width: 760px; }
.related-tools ul { margin: 8px 0 0; padding-left: 20px; }
.related-tools li { margin-bottom: 6px; }
.last-updated { font-size: .85rem; color: var(--text-muted); margin: 24px 0 8px; }

/* Content pages */
.page-content { max-width: 760px; padding: 32px 0 48px; }
.page-content ul { margin: 0 0 1em; padding-left: 22px; }
.page-content li { margin-bottom: .4em; }

/* Footer */
.site-footer { background: var(--bg-soft); border-top: 1px solid var(--border); margin-top: 48px; padding: 36px 0 24px; font-size: .92rem; color: var(--text-muted); }
.footer-inner { display: flex; flex-wrap: wrap; gap: 32px; justify-content: space-between; }
.footer-col h3 { font-size: .95rem; color: var(--text); margin-bottom: .6em; }
.footer-col ul { list-style: none; margin: 0; padding: 0; }
.footer-col li { margin-bottom: 6px; }
.footer-col a { color: var(--text-muted); }
.footer-bottom { margin-top: 28px; padding-top: 16px; border-top: 1px solid var(--border); text-align: center; font-size: .85rem; }

@media (max-width: 720px) {
  h1 { font-size: 1.6rem; }
  .hero h1 { font-size: 1.8rem; }
  .nav-toggle { display: block; }
  .main-nav { display: none; flex-direction: column; width: 100%; padding: 8px 0; }
  .main-nav.open { display: flex; }
  .header-inner { flex-wrap: wrap; }
  .tool-box { padding: 18px; }
  .result-main { font-size: 1.5rem; }
}