:root {
  --bg: #f7f8fa;
  --surface: #ffffff;
  --border: #e2e5ea;
  --text: #1c1f26;
  --text-muted: #5b6270;
  --brand: #2f6fed;
  --brand-dark: #1d4fc4;
  --code-bg: #f1f3f6;
  --danger: #d64545;
  --success: #1a8f5e;
  --radius: 10px;
  --sidebar-w: 280px;
}

* { box-sizing: border-box; }

html { color-scheme: light; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
}

img { max-width: 100%; }

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

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--brand);
  color: #fff;
  padding: 8px 14px;
  z-index: 100;
}
.skip-link:focus { left: 8px; top: 8px; }

#app {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar-toggle-input { display: none; }
.sidebar-mask {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,.4);
  z-index: 20;
}

#sidebar {
  width: var(--sidebar-w);
  flex: 0 0 var(--sidebar-w);
  background: var(--surface);
  border-right: 1px solid var(--border);
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}
.sidebar-inner { padding: 20px 16px 60px; }

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--text);
  margin-bottom: 18px;
}
.brand:hover { text-decoration: none; }

.nav-section { margin-bottom: 4px; }
.nav-section > summary {
  cursor: pointer;
  font-weight: 600;
  font-size: .78rem;
  text-transform: uppercase;
  letter-spacing: .04em;
  color: var(--text-muted);
  padding: 10px 4px;
  list-style: none;
}
.nav-section > summary::-webkit-details-marker { display: none; }
.nav-heading {
  font-weight: 600;
  font-size: .78rem;
  text-transform: uppercase;
  letter-spacing: .04em;
  color: var(--text-muted);
  padding: 10px 4px 4px;
  margin: 0;
}

#sidebar nav ol {
  list-style: none;
  margin: 0 0 6px;
  padding: 0;
}
#sidebar nav a {
  display: block;
  padding: 7px 10px;
  border-radius: 8px;
  color: var(--text);
  font-size: .92rem;
}
#sidebar nav a:hover { background: var(--code-bg); text-decoration: none; }
#sidebar nav li.active a { background: var(--brand); color: #fff; }

/* Content */
#content { flex: 1; min-width: 0; display: flex; flex-direction: column; }

.topbar {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
  position: sticky;
  top: 0;
  z-index: 15;
}
.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 8px;
  cursor: pointer;
}
.icon-btn:hover { background: var(--code-bg); }
.mobile-brand { margin-bottom: 0; }

main { flex: 1; padding: 32px 40px 60px; max-width: 920px; width: 100%; margin: 0 auto; }

/* Home */
.hero { padding: 8px 0 28px; }
.hero h1 { font-size: 2rem; margin-bottom: 8px; }
.hero p { color: var(--text-muted); font-size: 1.05rem; max-width: 640px; }

.category-block { margin-bottom: 32px; }
.category-block h2 { font-size: 1.2rem; margin-bottom: 12px; }
.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 12px;
}
.tool-card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  color: var(--text);
}
.tool-card:hover { border-color: var(--brand); text-decoration: none; box-shadow: 0 2px 10px rgba(0,0,0,.05); }
.tool-card strong { display: block; margin-bottom: 4px; }
.tool-card span { color: var(--text-muted); font-size: .88rem; }

/* Tool pages */
.tool-header { margin-bottom: 18px; }
.eyebrow {
  text-transform: uppercase;
  font-size: .75rem;
  letter-spacing: .05em;
  color: var(--brand);
  font-weight: 700;
  margin: 0 0 6px;
}
.tool-header h1 { margin: 0 0 8px; font-size: 1.7rem; }
.tool-lead { color: var(--text-muted); margin: 0; font-size: 1.02rem; }

.tool-widget, .widget {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  margin: 20px 0;
}

.field { margin-bottom: 14px; }
.field label {
  display: block;
  font-weight: 600;
  font-size: .88rem;
  margin-bottom: 6px;
}
.field-row { display: flex; gap: 12px; flex-wrap: wrap; }
.field-row .field { flex: 1; min-width: 160px; }

textarea, input[type="text"], input[type="number"], input[type="search"], input[type="url"], select {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font: inherit;
  background: #fff;
  color: var(--text);
}
textarea { min-height: 140px; resize: vertical; font-family: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace; font-size: .92rem; }
input:focus, textarea:focus, select:focus { outline: 2px solid var(--brand); outline-offset: 1px; }

.checkbox-row { display: flex; align-items: center; gap: 8px; }
.checkbox-row input { width: auto; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 18px;
  border-radius: 8px;
  border: 1px solid transparent;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
}
.btn-primary { background: var(--brand); color: #fff; }
.btn-primary:hover { background: var(--brand-dark); }
.btn-secondary { background: var(--code-bg); color: var(--text); border-color: var(--border); }
.btn-secondary:hover { background: #e6e9ee; }
.btn-row { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 6px; }

.output-box {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px;
  white-space: pre-wrap;
  word-break: break-word;
  font-family: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace;
  font-size: .92rem;
  min-height: 44px;
}

.result-line { display: flex; justify-content: space-between; padding: 6px 0; border-bottom: 1px dashed var(--border); font-size: .95rem; }
.result-line:last-child { border-bottom: none; }
.result-line strong { color: var(--text-muted); font-weight: 600; }

.stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 10px; margin-top: 10px; }
.stat-box { background: var(--code-bg); border-radius: 8px; padding: 10px 12px; text-align: center; }
.stat-box .num { font-size: 1.3rem; font-weight: 700; }
.stat-box .label { font-size: .78rem; color: var(--text-muted); }

.swatch { display: inline-block; width: 100%; height: 60px; border-radius: 8px; border: 1px solid var(--border); }
.swatch-row { display: grid; grid-template-columns: repeat(auto-fill, minmax(110px, 1fr)); gap: 10px; margin-top: 12px; }
.swatch-item { text-align: center; font-size: .82rem; }
.swatch-item code { display: block; margin-top: 4px; }

.hint { font-size: .85rem; color: var(--text-muted); margin-top: 6px; }
.error-text { color: var(--danger); font-size: .88rem; margin-top: 6px; }
.success-text { color: var(--success); font-size: .88rem; margin-top: 6px; }

.tool-article { margin-top: 32px; }
.tool-article h2 { font-size: 1.25rem; margin: 28px 0 10px; }
.tool-article h3 { font-size: 1.05rem; margin: 20px 0 8px; }
.tool-article p, .tool-article li { color: var(--text); }
.tool-article ol, .tool-article ul { padding-left: 22px; }
.tool-article code { background: var(--code-bg); padding: 1px 6px; border-radius: 4px; font-size: .9em; }

/* Ads */
.ad-slot { margin: 24px 0; text-align: center; }
.ad-label { font-size: .7rem; text-transform: uppercase; letter-spacing: .05em; color: var(--text-muted); margin: 0 0 6px; }

/* Static pages */
.static-page .tool-article h2 { margin-top: 24px; }

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--surface);
  padding: 32px 40px;
  margin-top: 40px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 24px;
  max-width: 920px;
  margin: 0 auto;
}
.footer-grid p { color: var(--text-muted); font-size: .9rem; }
.footer-heading { font-weight: 700; font-size: .85rem; margin: 0 0 8px; }
.footer-grid ul { list-style: none; padding: 0; margin: 0; }
.footer-grid li { margin-bottom: 6px; font-size: .9rem; }
.copyright { text-align: center; color: var(--text-muted); font-size: .82rem; max-width: 920px; margin: 24px auto 0; }

/* Cookie banner */
.cookie-banner {
  position: fixed;
  left: 16px;
  right: 16px;
  bottom: 16px;
  max-width: 560px;
  margin: 0 auto;
  background: var(--text);
  color: #fff;
  padding: 16px 18px;
  border-radius: var(--radius);
  z-index: 50;
  box-shadow: 0 6px 24px rgba(0,0,0,.25);
}
.cookie-banner p { margin: 0 0 12px; font-size: .88rem; }
.cookie-banner a { color: #9cc0ff; }
.cookie-actions { display: flex; gap: 10px; justify-content: flex-end; }
.cookie-banner .btn-secondary { background: rgba(255,255,255,.12); color: #fff; border-color: rgba(255,255,255,.2); }
.cookie-banner .btn-secondary:hover { background: rgba(255,255,255,.2); }

/* Responsive */
@media (max-width: 900px) {
  #sidebar {
    position: fixed;
    z-index: 30;
    left: 0;
    top: 0;
    transform: translateX(-100%);
    transition: transform .2s ease;
    box-shadow: 0 0 0 rgba(0,0,0,0);
  }
  .sidebar-toggle-input:checked ~ #sidebar { transform: translateX(0); box-shadow: 0 0 30px rgba(0,0,0,.2); }
  .sidebar-toggle-input:checked ~ .sidebar-mask { display: block; }
  .topbar { display: flex; }
  main { padding: 20px 16px 48px; }
  .site-footer { padding: 24px 16px; }
  .footer-grid { grid-template-columns: 1fr; }
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14161b;
    --surface: #1b1e25;
    --border: #2b2f38;
    --text: #eef0f3;
    --text-muted: #a3a9b5;
    --code-bg: #22262f;
  }
  textarea, input, select { background: #14161b; color: var(--text); border-color: var(--border); }
}