/* CyberReady — Premium Professional Design */

:root {
  /* Dark, authoritative palette */
  --bg-primary: #0a0e17;
  --bg-secondary: #111827;
  --bg-card: #1a2332;
  --bg-card-hover: #1f2b3d;
  --bg-input: #0f1724;

  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --accent-glow: rgba(59, 130, 246, 0.15);

  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;

  --grade-a: #10b981;
  --grade-b: #3b82f6;
  --grade-c: #f59e0b;
  --grade-d: #f97316;
  --grade-f: #ef4444;

  --border: #1e293b;
  --border-light: #334155;

  --radius: 8px;
  --radius-lg: 12px;

  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

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

/* ─── Typography ───────────────────────────────────── */

h1, h2, h3, h4 {
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.01em;
}

h1 { font-size: 2.25rem; }
h2 { font-size: 1.75rem; }
h3 { font-size: 1.25rem; }

.text-muted { color: var(--text-muted); }
.text-secondary { color: var(--text-secondary); }
.text-accent { color: var(--accent); }
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-danger { color: var(--danger); }

/* ─── Layout ───────────────────────────────────────── */

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

.container-sm {
  max-width: 600px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ─── Navigation ───────────────────────────────────── */

.nav {
  background: rgba(10, 14, 23, 0.9);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: 0 24px;
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.nav-brand {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.nav-brand span {
  color: var(--accent);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-link {
  color: var(--text-secondary);
  padding: 8px 16px;
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 500;
  transition: all 0.15s;
}

.nav-link:hover {
  color: var(--text-primary);
  background: var(--bg-card);
}

/* ─── Buttons ──────────────────────────────────────── */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 24px;
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all 0.15s;
  font-family: var(--font);
  gap: 8px;
}

.btn-primary {
  background: var(--accent);
  color: white;
}

.btn-primary:hover {
  background: var(--accent-hover);
  box-shadow: 0 0 20px var(--accent-glow);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-light);
}

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent);
}

.btn-lg {
  padding: 14px 32px;
  font-size: 1rem;
  border-radius: var(--radius-lg);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ─── Cards ────────────────────────────────────────── */

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
}

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}

/* ─── Forms ────────────────────────────────────────── */

.form-group {
  margin-bottom: 20px;
}

.form-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.form-input {
  width: 100%;
  padding: 12px 16px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-primary);
  font-size: 1rem;
  font-family: var(--font);
  transition: border-color 0.15s;
}

.form-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

.form-input::placeholder {
  color: var(--text-muted);
}

/* ─── Grade Badges ─────────────────────────────────── */

.grade-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 10px;
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.grade-badge-lg {
  width: 80px;
  height: 80px;
  font-size: 2.5rem;
  border-radius: 16px;
}

.grade-badge-xl {
  width: 120px;
  height: 120px;
  font-size: 3.5rem;
  border-radius: 20px;
}

.grade-A { background: rgba(16, 185, 129, 0.15); color: var(--grade-a); border: 2px solid var(--grade-a); }
.grade-B { background: rgba(59, 130, 246, 0.15); color: var(--grade-b); border: 2px solid var(--grade-b); }
.grade-C { background: rgba(245, 158, 11, 0.15); color: var(--grade-c); border: 2px solid var(--grade-c); }
.grade-D { background: rgba(249, 115, 22, 0.15); color: var(--grade-d); border: 2px solid var(--grade-d); }
.grade-F { background: rgba(239, 68, 68, 0.15); color: var(--grade-f); border: 2px solid var(--grade-f); }

/* ─── Score Display ────────────────────────────────── */

.score-display {
  text-align: center;
  padding: 40px 0;
}

.score-number {
  font-size: 4rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1;
}

.score-label {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-top: 8px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

/* ─── Alerts / Messages ───────────────────────────── */

.alert {
  padding: 12px 16px;
  border-radius: var(--radius);
  font-size: 0.875rem;
  margin-bottom: 16px;
}

.alert-error {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.3);
  color: #fca5a5;
}

.alert-success {
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.3);
  color: #6ee7b7;
}

.alert-info {
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: #93c5fd;
}

/* ─── Footer ───────────────────────────────────────── */

.footer {
  border-top: 1px solid var(--border);
  padding: 32px 24px;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.8125rem;
  margin-top: 80px;
}

/* ─── Utility ──────────────────────────────────────── */

.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mt-4 { margin-top: 32px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }
.mb-4 { margin-bottom: 32px; }
.text-center { text-align: center; }
.flex { display: flex; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: 16px; }
.gap-3 { gap: 24px; }
.hidden { display: none; }

/* ─── Loading spinner ──────────────────────────────── */

.spinner {
  width: 24px;
  height: 24px;
  border: 3px solid var(--border-light);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ─── Responsive ───────────────────────────────────── */

@media (max-width: 768px) {
  h1 { font-size: 1.75rem; }
  .container { padding: 0 16px; }
  .nav-links { gap: 4px; }
  .nav-link { padding: 8px 10px; font-size: 0.8125rem; }
}