:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-dark: #1e40af;
  --primary-deep: #1e3a5f;
  --primary-soft: #dbeafe;
  --primary-softest: #eff6ff;
  --brand-gradient: linear-gradient(135deg, #1e3a5f 0%, #2563eb 50%, #1e40af 100%);

  --ink: #111827;
  --ink-soft: #1f2937;
  --body: #4b5563;
  --muted: #6b7280;
  --disabled: #9ca3af;

  --canvas: #f0f2f5;
  --surface: #ffffff;
  --surface-soft: #f9fafb;
  --surface-muted: #f3f4f6;

  --border: #e5e7eb;
  --border-strong: #d1d5db;

  --on-primary: #ffffff;
  --footer-dark: #111827;

  --success: #10b981;
  --success-soft: #ecfdf5;
  --warning: #f59e0b;
  --warning-soft: #fffbeb;
  --danger: #ef4444;
  --danger-soft: #fef2f2;

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, .06), 0 1px 3px rgba(0, 0, 0, .10);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, .08), 0 2px 4px -1px rgba(0, 0, 0, .04);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, .08), 0 4px 6px -2px rgba(0, 0, 0, .04);
  --shadow-xl: 0 24px 60px rgba(15, 23, 42, .22);
  --shadow-focus: 0 0 0 3px rgba(59, 130, 246, .35);

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-pill: 999px;

  /* Backwards-compat aliases used by existing rules. */
  --bg: var(--canvas);
  --bg-2: var(--primary-softest);
  --line: var(--border);
  --text: var(--ink);
  --blue: var(--primary);
  --blue-2: var(--primary-dark);
  --shadow: var(--shadow-md);
  --radius: var(--radius-sm);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--canvas);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-hover); }
img { max-width: 100%; }

h1, h2, h3, h4 {
  margin: 0 0 10px;
  color: var(--ink);
  letter-spacing: -0.01em;
  font-weight: 700;
}
h1 { letter-spacing: -0.02em; font-weight: 800; }

p { color: var(--body); line-height: 1.6; }

table { width: 100%; border-collapse: collapse; font-size: 14px; }
th, td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
  color: var(--ink-soft);
}
th {
  color: var(--muted);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  font-weight: 600;
  background: var(--surface-soft);
}

input, select, textarea {
  width: 100%;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  padding: 11px 12px;
  font: inherit;
  background: var(--surface);
  color: var(--ink);
  transition: border-color 150ms ease, box-shadow 150ms ease;
}
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: var(--shadow-focus);
}
textarea { min-height: 92px; resize: vertical; }

label {
  display: grid;
  gap: 6px;
  color: var(--ink-soft);
  font-weight: 600;
  font-size: 13px;
}

pre {
  white-space: pre-wrap;
  background: var(--surface-muted);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 14px;
  overflow: auto;
  color: var(--ink-soft);
  font-size: 13px;
}

.primary-button, .soft-button, .ghost-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  border: 0;
  border-radius: var(--radius-sm);
  padding: 0 24px;
  font-weight: 600;
  font-size: 16px;
  cursor: pointer;
  transition: transform 150ms ease, box-shadow 150ms ease, background 150ms ease, color 150ms ease, border-color 150ms ease;
  text-decoration: none;
}
.primary-button {
  color: var(--on-primary);
  background: var(--primary);
  box-shadow: var(--shadow-sm);
}
.primary-button:hover {
  background: var(--primary-hover);
  color: var(--on-primary);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}
.primary-button:active {
  background: var(--primary-dark);
  transform: translateY(0);
}

.soft-button {
  color: var(--primary);
  background: var(--primary-softest);
  border: 1px solid var(--primary-soft);
}
.soft-button:hover {
  background: var(--primary-soft);
  color: var(--primary-dark);
}

.ghost-button {
  color: var(--ink-soft);
  background: var(--surface);
  border: 2px solid var(--border-strong);
  width: 100%;
}
.ghost-button:hover {
  background: var(--surface-muted);
  border-color: var(--primary);
  color: var(--primary);
}

.flash {
  max-width: 900px;
  margin: 16px auto;
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  background: var(--primary-softest);
  color: var(--primary-dark);
  border: 1px solid var(--primary-soft);
  font-weight: 500;
}
.flash.error {
  background: var(--danger-soft);
  color: #991b1b;
  border-color: #fecaca;
}
.flash.success {
  background: var(--success-soft);
  color: #047857;
  border-color: #bbf7d0;
}