/* ═══════════════════════════════════════════════════════
   AI Adventures — Design System
   Aesthetic: Playful sci-fi notebook. Like a kid's journal
   from the future. Warm + digital. Not generic.
   ═══════════════════════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=Nunito:wght@400;600;700;800;900&family=Space+Mono:wght@400;700&family=Fraunces:ital,opsz,wght@0,9..144,300;1,9..144,500&display=swap');

:root {
  /* Core palette */
  --ink:       #1A1826;
  --ink-soft:  #3D3A52;
  --muted:     #7E7A96;
  --border:    #E2DFF0;
  --surface:   #F7F5FF;
  --white:     #FFFFFF;

  /* Module accent colours */
  --m1: #7C6FE0;   --m1-l: #EEEDFE;  /* purple  – Understanding AI */
  --m2: #0EB07A;   --m2-l: #E2F6EF;  /* teal    – Prompts */
  --m3: #E07C3A;   --m3-l: #FEF0E6;  /* amber   – HTML */
  --m4: #3A8CE0;   --m4-l: #E6F1FE;  /* blue    – Python */
  --m5: #C04ECC;   --m5-l: #F8E6FF;  /* violet  – Project */

  /* Semantic */
  --correct:   #0EB07A;
  --wrong:     #E05A3A;
  --pending:   #E0A83A;

  /* Type scale */
  --font-display: 'Fraunces', Georgia, serif;
  --font-body:    'Nunito', system-ui, sans-serif;
  --font-code:    'Space Mono', monospace;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --radius-xl: 32px;

  --shadow-sm: 0 2px 8px rgba(26,24,38,.07);
  --shadow-md: 0 4px 20px rgba(26,24,38,.10);
  --shadow-lg: 0 8px 40px rgba(26,24,38,.14);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  background: var(--surface);
  color: var(--ink);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* ── Dot-grid background ── */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image: radial-gradient(circle, #C5BEEE 1px, transparent 1px);
  background-size: 28px 28px;
  opacity: .35;
  pointer-events: none;
  z-index: 0;
}

/* ── Typography ── */
h1,h2,h3,h4 { font-family: var(--font-display); line-height: 1.2; }
h1 { font-size: clamp(2rem, 5vw, 3.2rem); font-weight: 300; font-style: italic; }
h2 { font-size: clamp(1.4rem, 3vw, 2rem); font-weight: 500; }
h3 { font-size: 1.15rem; font-weight: 600; font-family: var(--font-body); }
p  { color: var(--ink-soft); }
code, .mono { font-family: var(--font-code); font-size: .88em; }

/* ── Cards ── */
.card {
  background: var(--white);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}
.card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--accent, var(--m1));
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  padding: .6rem 1.4rem;
  border-radius: 999px;
  font-family: var(--font-body);
  font-weight: 700;
  font-size: .9rem;
  border: 2px solid transparent;
  cursor: pointer;
  transition: all .2s ease;
  text-decoration: none;
}
.btn-primary {
  background: var(--ink);
  color: var(--white);
}
.btn-primary:hover {
  background: var(--ink-soft);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}
.btn-outline {
  background: transparent;
  border-color: var(--border);
  color: var(--ink-soft);
}
.btn-outline:hover {
  border-color: var(--muted);
  background: var(--surface);
}
.btn-accent {
  background: var(--accent, var(--m1));
  color: white;
}
.btn-accent:hover {
  filter: brightness(1.1);
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(0,0,0,.15);
}

/* ── Badge ── */
.badge {
  display: inline-flex;
  align-items: center;
  gap: .3rem;
  padding: .2rem .75rem;
  border-radius: 999px;
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .02em;
  text-transform: uppercase;
}

/* ── Progress bar ── */
.progress-track {
  height: 8px;
  background: var(--border);
  border-radius: 99px;
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  background: var(--accent, var(--m1));
  border-radius: 99px;
  transition: width .6s cubic-bezier(.4,0,.2,1);
}

/* ── Quiz elements ── */
.quiz-option {
  display: flex;
  align-items: center;
  gap: .75rem;
  padding: .85rem 1.1rem;
  border: 2px solid var(--border);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all .18s ease;
  background: var(--white);
  font-weight: 600;
  user-select: none;
}
.quiz-option:hover:not(.locked) {
  border-color: var(--accent, var(--m1));
  background: var(--accent-l, var(--m1-l));
  transform: translateX(4px);
}
.quiz-option.correct {
  border-color: var(--correct);
  background: #E2F6EF;
  color: #0B6E49;
}
.quiz-option.wrong {
  border-color: var(--wrong);
  background: #FDE8E3;
  color: #7A2210;
}
.quiz-option.locked { cursor: default; }

.option-circle {
  width: 32px; height: 32px;
  border-radius: 50%;
  border: 2px solid var(--border);
  display: flex; align-items: center; justify-content: center;
  font-size: .8rem; font-weight: 700;
  flex-shrink: 0;
  transition: all .18s;
}
.quiz-option:hover:not(.locked) .option-circle {
  border-color: var(--accent, var(--m1));
  background: var(--accent, var(--m1));
  color: white;
}
.quiz-option.correct .option-circle { border-color: var(--correct); background: var(--correct); color: white; }
.quiz-option.wrong   .option-circle { border-color: var(--wrong);   background: var(--wrong);   color: white; }

/* ── Feedback box ── */
.feedback-box {
  padding: 1rem 1.25rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  display: none;
  animation: slideDown .25s ease;
}
.feedback-box.show { display: block; }
.feedback-box.correct { background: #E2F6EF; color: #0B6E49; border: 1.5px solid #6FCFAD; }
.feedback-box.wrong   { background: #FDE8E3; color: #7A2210; border: 1.5px solid #F0A090; }

@keyframes slideDown {
  from { opacity:0; transform: translateY(-8px); }
  to   { opacity:1; transform: translateY(0); }
}

/* ── Score ring ── */
.score-ring {
  width: 80px; height: 80px;
  border-radius: 50%;
  background: conic-gradient(var(--accent, var(--m1)) var(--pct, 0%), var(--border) 0%);
  display: flex; align-items: center; justify-content: center;
  font-weight: 900;
  font-size: 1.1rem;
  position: relative;
}
.score-ring::before {
  content: '';
  position: absolute;
  inset: 8px;
  border-radius: 50%;
  background: white;
}
.score-ring span { position: relative; z-index: 1; }

/* ── Animations ── */
@keyframes fadeUp {
  from { opacity:0; transform:translateY(20px); }
  to   { opacity:1; transform:translateY(0); }
}
@keyframes pop {
  0%   { transform: scale(1); }
  50%  { transform: scale(1.15); }
  100% { transform: scale(1); }
}
@keyframes shimmer {
  from { background-position: -200% center; }
  to   { background-position:  200% center; }
}
@keyframes float {
  0%,100% { transform: translateY(0); }
  50%      { transform: translateY(-8px); }
}
@keyframes starBurst {
  0%   { opacity:1; transform:scale(0) rotate(0deg); }
  60%  { opacity:1; transform:scale(1.4) rotate(180deg); }
  100% { opacity:0; transform:scale(1.6) rotate(360deg); }
}

.fade-up { animation: fadeUp .5s ease both; }
.float   { animation: float 3s ease-in-out infinite; }

/* ── Stagger helpers ── */
.stagger > * { animation: fadeUp .5s ease both; }
.stagger > *:nth-child(1) { animation-delay: .05s; }
.stagger > *:nth-child(2) { animation-delay: .10s; }
.stagger > *:nth-child(3) { animation-delay: .15s; }
.stagger > *:nth-child(4) { animation-delay: .20s; }
.stagger > *:nth-child(5) { animation-delay: .25s; }
.stagger > *:nth-child(6) { animation-delay: .30s; }

/* ── Nav ── */
.top-nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(247,245,255,.92);
  backdrop-filter: blur(12px);
  border-bottom: 1.5px solid var(--border);
  padding: .75rem 2rem;
  display: flex; align-items: center; gap: 1rem;
}
.nav-logo {
  font-family: var(--font-display);
  font-style: italic;
  font-size: 1.2rem;
  font-weight: 300;
  color: var(--ink);
  text-decoration: none;
}
.nav-spacer { flex: 1; }

/* ── Layout helpers ── */
.container { max-width: 960px; margin: 0 auto; padding: 0 1.5rem; }
.container-wide { max-width: 1200px; margin: 0 auto; padding: 0 1.5rem; }
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.grid-3 { display: grid; grid-template-columns: repeat(3,1fr); gap: 1rem; }
.grid-auto { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 1rem; }
.flex-center { display:flex; align-items:center; justify-content:center; }
.flex-between { display:flex; align-items:center; justify-content:space-between; }
.gap-1 { gap: .5rem; }
.gap-2 { gap: 1rem; }
.mt-1 { margin-top: .5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }

@media (max-width: 640px) {
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
  .top-nav { padding: .75rem 1rem; }
  .container { padding: 0 1rem; }
}