/* GrowChart blog + tools UI — shared header, article layout, dark mode.
   Mirrors the landing design tokens so blog/tool pages feel identical. */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --font-display: 'Manrope', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;

  --bg: #f7f9fb;
  --surface: #ffffff;
  --surface-secondary: #f4f8fc;
  --border: #e2e8f0;

  --primary: #001732;
  --primary-accent: #1960a6;
  --primary-soft: #85b7eb;

  --text: #0f172a;
  --text-muted: #475569;
  --text-subtle: #94a3b8;

  --success: #16a34a;
  --warning: #f59e0b;
  --danger: #dc2626;

  --shadow-sm: 0 1px 3px rgba(4, 44, 83, 0.05);
  --shadow-card: 0 8px 30px rgba(4, 44, 83, 0.06);
}

html.dark {
  --bg: #0f172a;
  --surface: #1e293b;
  --surface-secondary: #0f172a;
  --border: #334155;

  --primary: #85b7eb;
  --primary-accent: #38bdf8;
  --primary-soft: #001732;

  --text: #f8fafc;
  --text-muted: #94a3b8;
  --text-subtle: #64748b;
}

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* ---------- Shared header (same as main landing) ---------- */
nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--surface) 92%, transparent);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}
.nav-logo { display: flex; align-items: center; gap: 8px; text-decoration: none; }
.nav-logo img { height: 28px; width: auto; }
html.dark .logo-light { display: none; }
html:not(.dark) .logo-dark { display: none; }
.nav-links { display: flex; gap: 24px; font-size: 0.875rem; font-weight: 500; color: var(--text-muted); align-items: center; }
.nav-links a { color: inherit; text-decoration: none; }
.nav-links a:hover { color: var(--text); }
.nav-right { display: flex; align-items: center; gap: 16px; }
.theme-toggle-btn {
  background: none; border: 1px solid var(--border); border-radius: 10px;
  padding: 6px 10px; font-size: 0.9rem; cursor: pointer; color: var(--text-muted);
}
.theme-toggle-btn:hover { border-color: var(--primary-accent); color: var(--text); }
.nav-cta {
  background: var(--primary-accent); color: #fff; text-decoration: none;
  font-size: 0.875rem; font-weight: 600; padding: 9px 18px; border-radius: 999px;
  transition: opacity .15s, transform .15s;
}
html.dark .nav-cta { background: var(--primary-accent); color: #0f172a; }
.nav-cta:hover { opacity: 0.9; transform: translateY(-1px); }

/* Language switcher */
.lang-switch { position: relative; }
.lang-switch summary { list-style: none; cursor: pointer; display: flex; align-items: center; gap: 6px; color: var(--text-muted); font-size: .875rem; font-weight: 600; padding: 6px 10px; border: 1px solid var(--border); border-radius: 10px; }
.lang-switch summary::-webkit-details-marker { display: none; }
.lang-switch[open] summary { border-color: var(--primary-accent); color: var(--primary-accent); }
.lang-menu { position: absolute; right: 0; top: calc(100% + 8px); width: 260px; max-height: 320px; overflow-y: auto; background: var(--surface); border: 1px solid var(--border); border-radius: 12px; box-shadow: var(--shadow-card); z-index: 60; }
.lang-item { display: flex; align-items: center; gap: 10px; width: 100%; padding: 8px 10px; border-radius: 10px; text-decoration: none; color: var(--text); font-size: .85rem; }
.lang-item:hover { background: rgba(56,189,248,.12); }
.lang-item.active { background: rgba(56,189,248,.18); font-weight: 700; }
.lang-item .en-name { margin-inline-start: auto; font-size: .7rem; color: var(--text-muted); }

@media (max-width: 768px) { .nav-links { display: none; } }

/* ---------- Article ---------- */
main { max-width: 760px; margin: 0 auto; padding: 48px 24px 24px; }
.post-header { margin-bottom: 36px; }
.post-badge {
  display: inline-block; font-size: .75rem; font-weight: 700; text-transform: uppercase;
  letter-spacing: .05em; color: var(--primary-accent);
  background: var(--surface-secondary); border: 1px solid var(--border);
  padding: 5px 12px; border-radius: 999px; margin-bottom: 18px;
}
.post-header h1 {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 4.5vw, 2.7rem);
  font-weight: 800; line-height: 1.2; color: var(--text);
}
.post-meta { margin-top: 12px; font-size: .85rem; color: var(--text-subtle); }

.post-body h2 {
  font-family: var(--font-display);
  font-size: 1.35rem; font-weight: 700; margin: 28px 0 10px; color: var(--text);
}
.post-body h3 { font-size: 1.1rem; font-weight: 700; margin: 22px 0 8px; color: var(--text); }
.post-body p { margin-bottom: 16px; color: var(--text-muted); }
.post-body a { color: var(--primary-accent); font-weight: 600; }
.post-body ul { margin: 0 0 16px 20px; color: var(--text-muted); }
.post-body li { margin-bottom: 6px; }

/* CTA button (used on every article + tool page) */
.cta-box {
  margin-top: 36px; padding: 28px; border-radius: 18px; text-align: center;
  background: var(--surface-secondary); border: 1px solid var(--border);
}
.cta-box h3 { font-family: var(--font-display); font-size: 1.25rem; font-weight: 800; color: var(--text); margin-bottom: 8px; }
.cta-box p { color: var(--text-muted); font-size: .95rem; margin-bottom: 16px; }
.btn-primary {
  display: inline-block; background: var(--primary-accent); color: #fff;
  font-weight: 700; font-size: .95rem; padding: 12px 26px; border-radius: 999px;
  text-decoration: none; transition: opacity .15s, transform .15s;
}
html.dark .btn-primary { color: #0f172a; }
.btn-primary:hover { opacity: .9; transform: translateY(-1px); }
.btn-secondary {
  display: inline-block; background: transparent; color: var(--text);
  font-weight: 600; font-size: .9rem; padding: 11px 22px; border-radius: 999px;
  border: 1px solid var(--border); text-decoration: none;
}
.btn-secondary:hover { border-color: var(--primary-accent); color: var(--primary-accent); }

/* ---------- Tools ---------- */
.tool-shell { max-width: 860px; margin: 0 auto; padding: 40px 24px 24px; }
.tool-card {
  background: var(--surface); border: 1px solid var(--border); border-radius: 18px;
  box-shadow: var(--shadow-card); padding: 28px;
}
.tool-card h1 { font-family: var(--font-display); font-size: clamp(1.5rem, 3.5vw, 2rem); font-weight: 800; color: var(--text); margin-bottom: 6px; }
.tool-card .tool-sub { color: var(--text-muted); margin-bottom: 24px; }
.tool-form { display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 14px; margin-bottom: 18px; }
.tool-form label { display: block; font-size: .8rem; font-weight: 600; color: var(--text-muted); margin-bottom: 5px; }
.tool-form input, .tool-form select {
  width: 100%; padding: 10px 12px; border: 1px solid var(--border); border-radius: 10px;
  background: var(--surface); color: var(--text); font-size: .95rem;
}
.tool-form input:focus, .tool-form select:focus { outline: 2px solid var(--primary-accent); outline-offset: 0; border-color: transparent; }
.tool-result {
  display: none; margin-top: 20px; padding: 22px; border-radius: 14px;
  background: var(--surface-secondary); border: 1px solid var(--border);
}
.tool-result.show { display: block; }
.tool-big {
  font-family: var(--font-display); font-size: 2.6rem; font-weight: 800; color: var(--primary-accent);
}
.tool-bars { margin: 14px 0; }
.tool-bar-row { display: grid; grid-template-columns: 64px 1fr 44px; gap: 8px; align-items: center; font-size: .75rem; color: var(--text-subtle); margin-bottom: 4px; }
.tool-bar-track { height: 8px; background: var(--border); border-radius: 999px; position: relative; }
.tool-bar-fill { height: 8px; border-radius: 999px; background: var(--primary-accent); }
.tool-flag {
  display: inline-block; margin-top: 8px; padding: 6px 14px; border-radius: 999px;
  font-size: .85rem; font-weight: 700;
}
.flag-normal { background: rgba(22,163,74,.14); color: var(--success); }
.flag-warn { background: rgba(245,158,11,.16); color: var(--warning); }
.flag-alert { background: rgba(220,38,38,.14); color: var(--danger); }

/* ---------- Footer ---------- */
footer {
  margin-top: 48px; padding: 28px 24px 40px; border-top: 1px solid var(--border);
  display: flex; flex-wrap: wrap; gap: 20px; justify-content: center; align-items: center;
  color: var(--text-subtle); font-size: .85rem;
}
footer a { color: var(--text-muted); text-decoration: none; }
footer a:hover { color: var(--primary-accent); }

@media (max-width: 768px) {
  main, .tool-shell { padding: 32px 18px 18px; }
  .tool-card { padding: 20px; }
  .tool-big { font-size: 2.1rem; }
}