/* ============================================================
   Typing Cert — design system
   ============================================================ */

:root {
  /* Colors */
  --bg-0:        #0a0f1c;   /* Page bg, deepest */
  --bg-1:        #0f172a;   /* Card bg */
  --bg-2:        #1e293b;   /* Raised surfaces */
  --bg-3:        #334155;   /* Borders, dividers */

  --text-0:      #f1f5f9;   /* Strongest text */
  --text-1:      #cbd5e1;   /* Body text */
  --text-2:      #94a3b8;   /* Muted */
  --text-3:      #64748b;   /* Disabled / very muted */

  --accent:      #38bdf8;   /* Primary accent */
  --accent-2:    #7dd3fc;   /* Hover */
  --accent-soft: rgba(56, 189, 248, 0.12);

  --success:     #4ade80;
  --warning:     #fbbf24;
  --danger:      #f87171;

  /* Typography */
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  --font-display: 'Inter', system-ui, sans-serif;
  --font-mono: 'SF Mono', Menlo, Monaco, Consolas, monospace;

  /* Spacing */
  --r-sm: 6px;
  --r-md: 10px;
  --r-lg: 14px;
  --r-xl: 20px;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.2);
  --shadow-md: 0 8px 24px rgba(0,0,0,0.25);
  --shadow-glow: 0 0 60px rgba(56, 189, 248, 0.15);

  --container: 1100px;
  --container-narrow: 740px;
}

/* Reset */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-body);
  background: var(--bg-0);
  color: var(--text-1);
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Subtle background gradient */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background:
    radial-gradient(ellipse at top, rgba(56, 189, 248, 0.08), transparent 50%),
    radial-gradient(ellipse at bottom right, rgba(99, 102, 241, 0.05), transparent 60%);
  pointer-events: none;
  z-index: -1;
}

a { color: var(--accent); text-decoration: none; transition: color 0.15s; }
a:hover { color: var(--accent-2); }

img { max-width: 100%; display: block; }

::selection { background: var(--accent-soft); color: var(--text-0); }

/* ============================================================
   Layout
   ============================================================ */
.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 1.5rem;
  width: 100%;
}
.container--narrow { max-width: var(--container-narrow); }

main { flex: 1; }
section { padding: 4rem 0; }
@media (max-width: 720px) { section { padding: 2.5rem 0; } }

/* ============================================================
   Typography
   ============================================================ */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  color: var(--text-0);
  letter-spacing: -0.02em;
  line-height: 1.2;
}
h1 { font-size: clamp(2rem, 4vw + 1rem, 3.5rem); font-weight: 800; }
h2 { font-size: clamp(1.5rem, 2vw + 1rem, 2.25rem); font-weight: 700; margin-bottom: 1rem; }
h3 { font-size: 1.25rem; font-weight: 600; margin-bottom: 0.5rem; }
h4 { font-size: 1.05rem; font-weight: 600; }

.lead {
  font-size: 1.15rem;
  color: var(--text-2);
  max-width: 60ch;
}
.eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  margin-bottom: 1.25rem;
}

.muted { color: var(--text-2); }
.small { font-size: 0.85rem; color: var(--text-3); }

/* ============================================================
   Header / Nav
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(10, 15, 28, 0.75);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--bg-2);
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
}
.nav-brand {
  font-weight: 800;
  font-size: 1.15rem;
  color: var(--text-0);
  display: flex;
  align-items: center;
  gap: 0.55rem;
  letter-spacing: -0.01em;
}
.nav-brand:hover { color: var(--text-0); }
.nav-brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--accent), #0ea5e9);
  color: white;
  font-weight: 800;
  font-size: 0.95rem;
}
.nav-links {
  display: flex;
  gap: 2rem;
  align-items: center;
  list-style: none;
}
.nav-links a {
  color: var(--text-2);
  font-size: 0.92rem;
  font-weight: 500;
}
.nav-links a:hover { color: var(--text-0); }
.nav-links a.active { color: var(--text-0); }
.nav-cta { margin-left: 0.5rem; }

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-0);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.25rem 0.5rem;
}

@media (max-width: 720px) {
  .nav-links { display: none; }
  .nav-toggle { display: block; }
  .nav-links.open {
    display: flex;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--bg-1);
    border-bottom: 1px solid var(--bg-2);
    gap: 0;
    padding: 0.5rem 0;
  }
  .nav-links.open li { width: 100%; }
  .nav-links.open a {
    display: block;
    padding: 0.85rem 1.5rem;
    width: 100%;
  }
  .nav-cta { margin: 0.5rem 1.5rem; }
}

/* ============================================================
   Buttons
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  padding: 0.7rem 1.4rem;
  border-radius: var(--r-md);
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.15s ease;
  white-space: nowrap;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent), #0ea5e9);
  color: var(--bg-0);
  box-shadow: 0 4px 14px rgba(56, 189, 248, 0.25);
}
.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(56, 189, 248, 0.35);
  color: var(--bg-0);
}
.btn-secondary {
  background: var(--bg-2);
  color: var(--text-0);
  border-color: var(--bg-3);
}
.btn-secondary:hover {
  background: var(--bg-3);
  color: var(--text-0);
}
.btn-ghost {
  background: transparent;
  color: var(--text-2);
}
.btn-ghost:hover { color: var(--text-0); }
.btn-lg { padding: 0.95rem 1.85rem; font-size: 1rem; }
.btn-block { width: 100%; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }

/* ============================================================
   Cards
   ============================================================ */
.card {
  background: var(--bg-1);
  border: 1px solid var(--bg-2);
  border-radius: var(--r-xl);
  padding: 2rem;
  transition: border-color 0.2s, transform 0.2s;
}
.card-hover:hover {
  border-color: var(--bg-3);
  transform: translateY(-2px);
}

/* ============================================================
   Hero
   ============================================================ */
.hero {
  padding: 6rem 0 4rem;
  text-align: center;
  position: relative;
}
.hero h1 { margin-bottom: 1.25rem; }
.hero .lead { margin: 0 auto 2rem; }
.hero-actions {
  display: flex;
  gap: 0.85rem;
  justify-content: center;
  flex-wrap: wrap;
}
.hero-shine {
  position: absolute;
  top: 20%;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(56, 189, 248, 0.15), transparent 60%);
  pointer-events: none;
  z-index: -1;
}

/* ============================================================
   Feature grid
   ============================================================ */
.grid {
  display: grid;
  gap: 1.5rem;
}
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
@media (max-width: 880px) {
  .grid-3 { grid-template-columns: 1fr; }
  .grid-2 { grid-template-columns: 1fr; }
}

.feature {
  background: var(--bg-1);
  border: 1px solid var(--bg-2);
  border-radius: var(--r-xl);
  padding: 2rem;
  transition: all 0.2s;
}
.feature:hover {
  border-color: var(--accent);
  background: var(--bg-2);
}
.feature-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 1.4rem;
  margin-bottom: 1.25rem;
}
.feature h3 { margin-bottom: 0.5rem; }

/* ============================================================
   Steps (numbered)
   ============================================================ */
.steps {
  counter-reset: step;
  display: grid;
  gap: 1.25rem;
}
.step-item {
  background: var(--bg-1);
  border: 1px solid var(--bg-2);
  border-radius: var(--r-lg);
  padding: 1.5rem 1.5rem 1.5rem 4.5rem;
  position: relative;
}
.step-item::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 1.25rem;
  top: 1.5rem;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.1rem;
}
.step-item h3 { margin-bottom: 0.4rem; }
.step-item p { color: var(--text-2); margin: 0; }

/* ============================================================
   Pricing card
   ============================================================ */
.pricing-card {
  background: linear-gradient(180deg, var(--bg-1), var(--bg-0));
  border: 1px solid var(--accent);
  border-radius: var(--r-xl);
  padding: 2.5rem;
  text-align: center;
  max-width: 420px;
  margin: 0 auto;
  position: relative;
  box-shadow: var(--shadow-glow);
}
.pricing-card::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--r-xl);
  padding: 1px;
  background: linear-gradient(135deg, var(--accent), transparent);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
}
.pricing-amount {
  font-size: 3.5rem;
  font-weight: 800;
  color: var(--text-0);
  letter-spacing: -0.03em;
  margin: 0.5rem 0;
}
.pricing-amount .currency {
  font-size: 1.5rem;
  vertical-align: super;
  margin-right: 0.1em;
}
.pricing-amount .period {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-2);
  margin-left: 0.4em;
}
.pricing-list {
  text-align: left;
  list-style: none;
  margin: 1.5rem 0;
  padding: 0;
}
.pricing-list li {
  padding: 0.55rem 0;
  color: var(--text-1);
  display: flex;
  align-items: flex-start;
  gap: 0.65rem;
}
.pricing-list li::before {
  content: '✓';
  color: var(--success);
  font-weight: 700;
  flex-shrink: 0;
}

/* ============================================================
   FAQ
   ============================================================ */
.faq-item {
  border-bottom: 1px solid var(--bg-2);
  padding: 1.25rem 0;
}
.faq-item summary {
  font-weight: 600;
  color: var(--text-0);
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 1.02rem;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: '+';
  font-size: 1.5rem;
  color: var(--accent);
  font-weight: 300;
  transition: transform 0.2s;
}
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item p { margin-top: 0.75rem; color: var(--text-2); }

/* ============================================================
   Forms
   ============================================================ */
.form-group { margin-bottom: 1.25rem; }
.form-label {
  display: block;
  font-size: 0.85rem;
  color: var(--text-2);
  margin-bottom: 0.4rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
}
.form-input, .form-textarea {
  width: 100%;
  background: var(--bg-0);
  border: 1px solid var(--bg-3);
  border-radius: var(--r-md);
  padding: 0.75rem 1rem;
  font-size: 1rem;
  color: var(--text-0);
  outline: none;
  font-family: inherit;
  transition: border-color 0.15s, box-shadow 0.15s;
}
.form-input:focus, .form-textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}
.form-textarea { min-height: 140px; resize: vertical; }

.alert {
  padding: 0.85rem 1.1rem;
  border-radius: var(--r-md);
  border-left: 3px solid;
  margin-bottom: 1rem;
  font-size: 0.92rem;
}
.alert-error { background: rgba(248,113,113,0.08); color: #fecaca; border-color: var(--danger); }
.alert-info  { background: var(--accent-soft); color: var(--text-1); border-color: var(--accent); }
.alert-warn  { background: rgba(251,191,36,0.08); color: #fde68a; border-color: var(--warning); }

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  background: var(--bg-1);
  border-top: 1px solid var(--bg-2);
  padding: 3rem 0 2rem;
  margin-top: auto;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 2rem;
}
@media (max-width: 720px) {
  .footer-grid { grid-template-columns: 1fr; gap: 2rem; }
}
.footer-brand { color: var(--text-2); max-width: 320px; }
.footer-col h4 {
  color: var(--text-0);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 1rem;
}
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 0.5rem; }
.footer-col a { color: var(--text-2); font-size: 0.92rem; }
.footer-col a:hover { color: var(--text-0); }
.footer-bottom {
  border-top: 1px solid var(--bg-2);
  padding-top: 1.5rem;
  text-align: center;
  color: var(--text-3);
  font-size: 0.85rem;
}

/* ============================================================
   Animations
   ============================================================ */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: none; }
}
.fade-in { animation: fadeInUp 0.5s ease both; }
.fade-in-2 { animation: fadeInUp 0.5s 0.1s ease both; }
.fade-in-3 { animation: fadeInUp 0.5s 0.2s ease both; }

/* ============================================================
   Utilities
   ============================================================ */
.text-center { text-align: center; }
.mt-1 { margin-top: 0.5rem; } .mt-2 { margin-top: 1rem; } .mt-3 { margin-top: 1.5rem; } .mt-4 { margin-top: 2rem; }
.mb-1 { margin-bottom: 0.5rem; } .mb-2 { margin-bottom: 1rem; } .mb-3 { margin-bottom: 1.5rem; } .mb-4 { margin-bottom: 2rem; }