:root {
  --bg: #ffffff;
  --bg-secondary: #f7f7f7;
  --fg: #171717;
  --fg-muted: #6b6b6b;
  --border: #e5e5e5;
  --accent: #171717;
  --accent-fg: #ffffff;
  --red: #dc2626;
  --red-bg: #fef2f2;
  --red-border: #fecaca;
  --green: #16a34a;
  --green-bg: #f0fdf4;
  --amber: #d97706;
  --mark-bg: #fef08a;
  --radius: 0.75rem;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Consolas, "Liberation Mono", Menlo, monospace;
}

[data-theme="dark"] {
  --bg: #0a0a0a;
  --bg-secondary: #171717;
  --fg: #ededed;
  --fg-muted: #a3a3a3;
  --border: #262626;
  --accent: #ffffff;
  --accent-fg: #0a0a0a;
  --red: #f87171;
  --red-bg: rgba(239, 68, 68, 0.12);
  --red-border: #7f1d1d;
  --green: #4ade80;
  --green-bg: rgba(34, 197, 94, 0.12);
  --amber: #fbbf24;
  --mark-bg: rgba(250, 204, 21, 0.3);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0a0a0a;
    --bg-secondary: #171717;
    --fg: #ededed;
    --fg-muted: #a3a3a3;
    --border: #262626;
    --accent: #ffffff;
    --accent-fg: #0a0a0a;
    --red: #f87171;
    --red-bg: rgba(239, 68, 68, 0.12);
    --red-border: #7f1d1d;
    --green: #4ade80;
    --green-bg: rgba(34, 197, 94, 0.12);
    --amber: #fbbf24;
    --mark-bg: rgba(250, 204, 21, 0.3);
  }
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--fg);
  display: flex;
  flex-direction: column;
  min-height: 100%;
}
main { flex: 1; }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; }

.container { max-width: 72rem; margin: 0 auto; padding: 0 1.25rem; }
.container-sm { max-width: 56rem; margin: 0 auto; padding: 0 1.25rem; }

/* Navbar */
.navbar {
  position: sticky; top: 0; z-index: 30;
  border-bottom: 1px solid var(--border);
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(8px);
}
.navbar-inner { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: 0.75rem 1.25rem; max-width: 72rem; margin: 0 auto; }
.brand { display: flex; align-items: center; gap: 0.5rem; font-weight: 600; font-size: 1rem; }
.nav-links { display: none; align-items: center; gap: 1.5rem; font-size: 0.875rem; color: var(--fg-muted); }
@media (min-width: 640px) { .nav-links { display: flex; } }
.nav-links a:hover { color: var(--fg); }
.icon-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 2.25rem; height: 2.25rem; border-radius: 0.5rem;
  border: 1px solid var(--border); background: transparent; color: var(--fg-muted); cursor: pointer;
}
.icon-btn:hover { background: var(--bg-secondary); }

/* Footer */
.footer { margin-top: auto; border-top: 1px solid var(--border); }
.footer-inner { padding: 2.5rem 1.25rem; max-width: 72rem; margin: 0 auto; }
.footer-grid { display: grid; gap: 2rem; grid-template-columns: 1fr; }
@media (min-width: 640px) { .footer-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 768px) { .footer-grid { grid-template-columns: repeat(4, 1fr); } }
.footer-title { font-weight: 600; }
.footer-desc { margin-top: 0.5rem; font-size: 0.875rem; color: var(--fg-muted); }
.footer-heading { font-size: 0.875rem; font-weight: 500; margin: 0 0 0.5rem; }
.footer ul { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 0.375rem; }
.footer a { font-size: 0.875rem; color: var(--fg-muted); }
.footer a:hover { color: var(--fg); }
.footer-note { margin-top: 2rem; font-size: 0.75rem; color: #a3a3a3; }

/* Hero */
.hero { max-width: 56rem; margin: 0 auto; padding: 4rem 1.25rem; text-align: center; }
.hero h1 { font-size: 2rem; font-weight: 600; letter-spacing: -0.02em; margin: 0; }
@media (min-width: 640px) { .hero { padding: 6rem 1.25rem; } .hero h1 { font-size: 3rem; } }
.hero p { margin-top: 1rem; color: var(--fg-muted); max-width: 36rem; margin-left: auto; margin-right: auto; }

/* Search */
.search-wrap { position: relative; width: 100%; max-width: 36rem; margin: 2rem auto 0; }
.search-box {
  display: flex; align-items: center; gap: 0.5rem;
  border: 1px solid var(--border); border-radius: 0.5rem; background: var(--bg);
  padding: 0.625rem 0.75rem; box-shadow: 0 1px 2px rgba(0,0,0,0.04);
}
.search-box input { flex: 1; border: none; outline: none; background: transparent; font-size: 0.875rem; color: var(--fg); }
.search-box input::placeholder { color: #a3a3a3; }
.search-results {
  position: absolute; z-index: 20; margin-top: 0.5rem; width: 100%;
  border: 1px solid var(--border); border-radius: 0.5rem; background: var(--bg);
  box-shadow: 0 8px 24px rgba(0,0,0,0.12); overflow: hidden; display: none;
}
.search-results.open { display: block; }
.search-result {
  display: block; padding: 0.625rem 1rem; border-bottom: 1px solid var(--border);
}
.search-result:last-child { border-bottom: none; }
.search-result:hover { background: var(--bg-secondary); }
.search-result-name { font-size: 0.875rem; font-weight: 500; }
.search-result-desc { font-size: 0.75rem; color: var(--fg-muted); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* Section headings */
.section { max-width: 72rem; margin: 0 auto; padding: 0 1.25rem 4rem; }
.section-head { display: flex; align-items: center; justify-content: space-between; }
.section-head h2 { font-size: 1.125rem; font-weight: 600; margin: 0; }
.section-head a { font-size: 0.875rem; color: var(--fg-muted); }
.section-head a:hover { color: var(--fg); }

/* Card grid */
.card-grid { display: grid; gap: 1rem; margin-top: 1rem; grid-template-columns: 1fr; }
@media (min-width: 640px) { .card-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1024px) { .card-grid { grid-template-columns: repeat(3, 1fr); } }
.card {
  display: block; border: 1px solid var(--border); border-radius: 0.75rem; padding: 1rem;
  transition: border-color 0.15s;
}
.card:hover { border-color: var(--fg-muted); }
.card-eyebrow { font-size: 0.6875rem; font-weight: 500; text-transform: uppercase; letter-spacing: 0.03em; color: var(--fg-muted); }
.card-title { margin-top: 0.25rem; font-weight: 500; }
.card-desc { margin-top: 0.25rem; font-size: 0.875rem; color: var(--fg-muted); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }

.cat-grid { display: grid; gap: 0.75rem; margin-top: 1rem; grid-template-columns: 1fr; }
@media (min-width: 640px) { .cat-grid { grid-template-columns: repeat(3, 1fr); } }
@media (min-width: 1024px) { .cat-grid { grid-template-columns: repeat(4, 1fr); } }
.cat-card { display: block; border: 1px solid var(--border); border-radius: 0.75rem; padding: 1rem; }
.cat-card:hover { border-color: var(--fg-muted); }
.cat-count { margin-top: 0.125rem; font-size: 0.75rem; color: var(--fg-muted); }

/* Breadcrumb / tool page header */
.breadcrumb { display: flex; align-items: center; gap: 0.375rem; font-size: 0.875rem; color: var(--fg-muted); margin-bottom: 1rem; }
.breadcrumb a:hover { color: var(--fg); }
.eyebrow { font-size: 0.75rem; font-weight: 500; text-transform: uppercase; letter-spacing: 0.03em; color: var(--fg-muted); margin-bottom: 0.5rem; }
.page-title { font-size: 1.5rem; font-weight: 600; margin: 0; }
@media (min-width: 640px) { .page-title { font-size: 1.875rem; } }
.page-desc { margin-top: 0.5rem; color: var(--fg-muted); max-width: 42rem; }

/* Tool shell */
.tool-shell { border: 1px solid var(--border); border-radius: 0.875rem; background: var(--bg); padding: 1rem; margin-top: 1.5rem; }
@media (min-width: 640px) { .tool-shell { padding: 1.5rem; } }
.tool-grid { display: grid; gap: 1rem; grid-template-columns: 1fr; }
@media (min-width: 768px) { .tool-grid { grid-template-columns: 1fr 1fr; } }
.panel-label-row { display: flex; align-items: center; justify-content: space-between; margin-bottom: 0.5rem; gap: 0.5rem; }
.panel-label { font-size: 0.75rem; font-weight: 500; text-transform: uppercase; letter-spacing: 0.03em; color: var(--fg-muted); }
.panel-actions { display: flex; align-items: center; gap: 0.375rem; }

textarea, input[type="text"], input[type="number"], input[type="datetime-local"], select {
  font-family: var(--font-sans); color: var(--fg); background: var(--bg-secondary);
  border: 1px solid var(--border); border-radius: 0.5rem; padding: 0.75rem; font-size: 0.875rem;
}
textarea:focus, input:focus, select:focus { outline: 2px solid var(--fg-muted); outline-offset: 1px; }
textarea.mono, input.mono, pre.mono, .output.mono { font-family: var(--font-mono); }
textarea { width: 100%; resize: none; }
.h-sm { height: 7rem; }
.h-md { height: 14rem; }
@media (min-width: 640px) { .h-md { height: 18rem; } }
.h-lg { height: 20rem; }
@media (min-width: 640px) { .h-lg { height: 28rem; } }

.btn {
  display: inline-flex; align-items: center; gap: 0.375rem; font-size: 0.8125rem; font-weight: 500;
  border-radius: 0.5rem; border: 1px solid var(--border); background: transparent; color: var(--fg-muted);
  padding: 0.375rem 0.625rem; cursor: pointer;
}
.btn:hover { background: var(--bg-secondary); }
.btn:disabled { opacity: 0.4; cursor: not-allowed; }
.btn-primary { background: var(--accent); color: var(--accent-fg); border-color: var(--accent); }
.btn-primary:hover { opacity: 0.9; background: var(--accent); }
.btn.copied { color: var(--green); }

.tabs { display: inline-flex; border: 1px solid var(--border); border-radius: 0.5rem; padding: 0.25rem; margin-bottom: 1rem; gap: 0.125rem; }
.tab { border: none; background: transparent; padding: 0.375rem 0.75rem; border-radius: 0.375rem; font-size: 0.875rem; font-weight: 500; color: var(--fg-muted); cursor: pointer; text-transform: capitalize; }
.tab.active { background: var(--accent); color: var(--accent-fg); }

.stat-bar { display: flex; flex-wrap: wrap; gap: 0 1rem; margin-top: 0.375rem; font-size: 0.6875rem; color: #a3a3a3; }

.output-error { border-color: var(--red-border) !important; background: var(--red-bg) !important; color: var(--red) !important; }
.error-text { font-size: 0.875rem; color: var(--red); margin-top: 0.5rem; padding: 0.75rem; border: 1px solid var(--red-border); background: var(--red-bg); border-radius: 0.5rem; }

/* Content article */
.article { max-width: 56rem; margin-top: 3rem; line-height: 1.7; }
.article h2 { font-size: 1.25rem; font-weight: 600; margin-top: 2rem; }
.article h3 { font-size: 1.0625rem; font-weight: 600; margin-top: 1.25rem; }
.article p { color: var(--fg); }
.article ol, .article ul { padding-left: 1.25rem; }

.related-grid { display: grid; gap: 0.75rem; margin-top: 0.75rem; grid-template-columns: 1fr; }
@media (min-width: 640px) { .related-grid { grid-template-columns: repeat(3, 1fr); } }

.row-item { display: flex; align-items: center; justify-content: space-between; gap: 0.5rem; border-radius: 0.5rem; background: var(--bg-secondary); padding: 0.5rem 0.75rem; margin-bottom: 0.5rem; }
.row-item .label { font-size: 0.6875rem; text-transform: uppercase; color: var(--fg-muted); }
.row-item .value { font-family: var(--font-mono); font-size: 0.8125rem; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

.pill { border-radius: 999px; border: 1px solid var(--border); padding: 0.375rem 0.75rem; font-size: 0.8125rem; color: var(--fg-muted); background: transparent; cursor: pointer; }
.pill:hover { background: var(--bg-secondary); }
.pill.active { background: var(--accent); color: var(--accent-fg); border-color: var(--accent); }

mark { background: var(--mark-bg); border-radius: 0.2em; color: inherit; }

.swatch { width: 2.75rem; height: 2.75rem; flex-shrink: 0; border-radius: 0.5rem; border: 1px solid var(--border); padding: 0; cursor: pointer; }

.checkbox-row { display: flex; align-items: center; gap: 0.5rem; font-size: 0.875rem; }
.field-row { display: flex; align-items: center; justify-content: space-between; gap: 1rem; font-size: 0.875rem; }
.field-row input[type="range"] { flex: 1; }

.muted { color: var(--fg-muted); }
.small { font-size: 0.8125rem; }
.mt-1 { margin-top: 0.25rem; } .mt-2 { margin-top: 0.5rem; } .mt-3 { margin-top: 0.75rem; } .mt-4 { margin-top: 1rem; }
.grid-3 { display: grid; gap: 0.75rem; grid-template-columns: 1fr; }
@media (min-width: 640px) { .grid-3 { grid-template-columns: repeat(3, 1fr); } }
.grid-2 { display: grid; gap: 0.75rem; grid-template-columns: 1fr; }
@media (min-width: 640px) { .grid-2 { grid-template-columns: repeat(2, 1fr); } }