/* DevTools Hub - global stylesheet */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #eff6ff;
  --text: #1f2937;
  --text-muted: #6b7280;
  --border: #e5e7eb;
  --bg: #f8fafc;
  --card: #ffffff;
  --success: #16a34a;
  --danger: #dc2626;
  --radius: 10px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container { width: 100%; max-width: 960px; margin: 0 auto; padding: 0 16px; }

/* Header */
.site-header {
  background: var(--card);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}
.logo {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
}
.logo:hover { color: var(--primary-dark); }
.main-nav { display: flex; gap: 20px; }
.main-nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 15px;
  font-weight: 500;
}
.main-nav a:hover { color: var(--primary); }

/* Main */
main { flex: 1; padding: 32px 0 48px; }

h1 { font-size: 28px; margin-bottom: 8px; line-height: 1.3; }
h2 { font-size: 22px; margin: 28px 0 12px; }
h3 { font-size: 18px; margin: 20px 0 10px; }
p { margin-bottom: 12px; }
ul, ol { margin: 0 0 12px 22px; }
li { margin-bottom: 6px; }
a { color: var(--primary); }
a:hover { color: var(--primary-dark); }

/* Cards */
.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 20px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.04);
}
.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
  margin-top: 16px;
}
.tool-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  text-decoration: none;
  color: var(--text);
  transition: transform 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease;
}
.tool-card:hover {
  transform: translateY(-2px);
  border-color: var(--primary);
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.12);
}
.tool-card h3 { margin: 0 0 6px; color: var(--primary); }
.tool-card p { margin: 0; color: var(--text-muted); font-size: 14px; }

/* Forms / tool inputs */
label { font-weight: 600; display: block; margin: 14px 0 6px; }
textarea, input[type="text"], input[type="number"], input[type="datetime-local"], select {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 15px;
  font-family: inherit;
  background: #fff;
  color: var(--text);
}
textarea { min-height: 120px; resize: vertical; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }
textarea:focus, input:focus, select:focus {
  outline: 2px solid var(--primary);
  outline-offset: -1px;
  border-color: var(--primary);
}
textarea.output { background: var(--primary-light); }

.btn {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 8px;
  padding: 10px 20px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.15s ease;
}
.btn:hover { background: var(--primary-dark); color: #fff; }
.btn-secondary {
  background: #fff;
  color: var(--text);
  border: 1px solid var(--border);
}
.btn-secondary:hover { background: var(--bg); color: var(--text); }
.btn-row { display: flex; flex-wrap: wrap; gap: 10px; margin: 16px 0; }

.status { margin-top: 12px; font-weight: 600; }
.status.ok { color: var(--success); }
.status.error { color: var(--danger); }
.hint { color: var(--text-muted); font-size: 13px; margin-top: 8px; }

/* FAQ */
.faq-item { margin-bottom: 16px; }
.faq-item summary {
  font-weight: 600;
  cursor: pointer;
  margin-bottom: 6px;
}
.faq-item p { margin: 0 0 8px; }

/* Footer */
.site-footer {
  background: var(--card);
  border-top: 1px solid var(--border);
  padding: 20px 0;
  text-align: center;
  color: var(--text-muted);
  font-size: 14px;
}
.site-footer p { margin-bottom: 4px; }
.site-footer a { color: var(--text-muted); text-decoration: underline; }
.site-footer a:hover { color: var(--primary); }

.error-card { text-align: center; padding: 60px 24px; }
.error-card h1 { font-size: 32px; }

/* Responsive */
@media (max-width: 640px) {
  h1 { font-size: 24px; }
  .main-nav { gap: 14px; }
  .card { padding: 18px; }
  .tool-grid { grid-template-columns: 1fr; }
}