/* ── KBTI Design System ── */
:root {
  --bg: #0c0e12;
  --bg-card: #141820;
  --bg-elevated: #1a1f2a;
  --border: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(255, 255, 255, 0.16);
  --text: #f0f2f5;
  --text-secondary: #8b95a8;
  --text-muted: #5c6578;
  --accent: #ff4d2e;
  --accent-glow: rgba(255, 77, 46, 0.35);
  --accent-soft: rgba(255, 77, 46, 0.12);
  --radius: 16px;
  --radius-sm: 10px;
  --radius-lg: 24px;
  --font: 'DM Sans', 'Noto Sans SC', system-ui, sans-serif;
  --transition: 0.28s cubic-bezier(0.4, 0, 0.2, 1);
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
  --safe-bottom: env(safe-area-inset-bottom, 0px);
}

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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  min-height: 100dvh;
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* ── Background ── */
.bg-grid {
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 30%, black 20%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.bg-glow {
  position: fixed;
  border-radius: 50%;
  filter: blur(100px);
  pointer-events: none;
  z-index: 0;
}

.bg-glow--1 {
  width: 500px; height: 500px;
  top: -150px; right: -100px;
  background: var(--accent-glow);
  opacity: 0.5;
}

.bg-glow--2 {
  width: 400px; height: 400px;
  bottom: -100px; left: -80px;
  background: rgba(46, 107, 255, 0.2);
  opacity: 0.4;
}

/* ── Layout ── */
.app {
  position: relative;
  z-index: 1;
  max-width: 560px;
  margin: 0 auto;
  padding: 24px 20px calc(32px + var(--safe-bottom));
  min-height: 100dvh;
}

.screen {
  display: none;
  animation: screenOut 0.2s ease forwards;
}

.screen.active {
  display: flex;
  flex-direction: column;
  animation: screenIn 0.4s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

@keyframes screenIn {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes screenOut {
  to { opacity: 0; }
}

/* ── Welcome ── */
.hero {
  text-align: center;
  padding: 48px 0 36px;
}

.hero-badge {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-secondary);
  border: 1px solid var(--border);
  border-radius: 100px;
  padding: 6px 14px;
  margin-bottom: 28px;
}

.hero-title {
  font-size: clamp(3.5rem, 12vw, 5rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1;
  margin-bottom: 8px;
}

.hero-k {
  color: var(--accent);
  text-shadow: 0 0 40px var(--accent-glow);
}

.hero-sub {
  font-size: 1.25rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 20px;
}

.hero-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.7;
}

.dimension-preview {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 40px;
}

.dim-chip {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
  font-size: 0.85rem;
  color: var(--text-secondary);
  transition: border-color var(--transition);
}

.dim-chip:hover { border-color: var(--border-hover); }

.dim-chip-key {
  display: block;
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
  margin-bottom: 2px;
  font-family: 'DM Sans', monospace;
}

.footer-note {
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 20px;
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font);
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow var(--transition), background var(--transition), opacity var(--transition);
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

.btn:active:not(:disabled) { transform: scale(0.97); }

.btn-primary {
  background: var(--accent);
  color: #fff;
  padding: 16px 32px;
  box-shadow: 0 4px 24px var(--accent-glow);
}

.btn-primary:hover {
  box-shadow: 0 6px 32px var(--accent-glow);
}

.btn-lg {
  width: 100%;
  padding: 18px 32px;
  font-size: 1.05rem;
  border-radius: var(--radius);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  padding: 12px 20px;
  border: 1px solid var(--border);
  margin-top: 16px;
  width: 100%;
}

.btn-ghost:hover:not(:disabled) {
  border-color: var(--border-hover);
  color: var(--text);
}

.btn:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

#btn-start { align-self: center; }

/* ── Quiz ── */
.quiz-header {
  margin-bottom: 24px;
}

.progress-wrap {
  display: flex;
  align-items: center;
  gap: 14px;
}

.progress-track {
  flex: 1;
  height: 6px;
  background: var(--bg-elevated);
  border-radius: 100px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), #ff8a65);
  border-radius: 100px;
  transition: width 0.45s cubic-bezier(0.4, 0, 0.2, 1);
}

.progress-text {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-secondary);
  font-variant-numeric: tabular-nums;
  min-width: 48px;
  text-align: right;
}

.question-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  box-shadow: var(--shadow);
  flex: 1;
}

.question-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

.q-section {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 4px 10px;
  border-radius: 100px;
}

.q-number {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
}

.q-text {
  font-size: clamp(1.1rem, 4vw, 1.3rem);
  font-weight: 600;
  line-height: 1.5;
  margin-bottom: 28px;
  letter-spacing: -0.01em;
}

.options-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.options-list.fade-in {
  animation: fadeUp 0.35s ease forwards;
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(10px); }
  to   { opacity: 1; transform: translateY(0); }
}

.option-btn {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  width: 100%;
  text-align: left;
  background: var(--bg-elevated);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px 18px;
  color: var(--text);
  font-family: var(--font);
  font-size: 0.95rem;
  line-height: 1.5;
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition), transform 0.15s ease;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  min-height: 56px;
}

.option-btn:hover {
  border-color: var(--border-hover);
  background: rgba(255, 255, 255, 0.04);
}

.option-btn:active { transform: scale(0.985); }

.option-btn.selected {
  border-color: var(--accent);
  background: var(--accent-soft);
  animation: selectPulse 0.3s ease;
}

@keyframes selectPulse {
  0%   { transform: scale(1); }
  50%  { transform: scale(0.98); }
  100% { transform: scale(1); }
}

.option-letter {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(255, 255, 255, 0.06);
  border-radius: 8px;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text-secondary);
  transition: background var(--transition), color var(--transition);
}

.option-btn.selected .option-letter {
  background: var(--accent);
  color: #fff;
}

.option-text { flex: 1; padding-top: 3px; }

/* ── Result ── */
.result-card {
  --type-color: var(--accent);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
  opacity: 0;
  transform: translateY(20px);
}

.result-card.reveal {
  animation: resultReveal 0.6s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

@keyframes resultReveal {
  to { opacity: 1; transform: translateY(0); }
}

.result-top {
  text-align: center;
  padding: 36px 24px 0;
  position: relative;
}

.result-top::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: linear-gradient(90deg, transparent, var(--type-color), transparent);
}

.result-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.result-code-wrap {
  margin-bottom: 8px;
}

.result-code {
  display: block;
  font-size: clamp(2.5rem, 8vw, 3.2rem);
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--type-color);
  text-shadow: 0 0 48px color-mix(in srgb, var(--type-color) 40%, transparent);
  line-height: 1.1;
}

.result-type-code {
  display: block;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-muted);
  letter-spacing: 0.15em;
  margin-top: 6px;
  font-family: 'DM Sans', monospace;
}

.result-name {
  font-size: clamp(1.4rem, 5vw, 1.75rem);
  font-weight: 700;
  margin-bottom: 10px;
  letter-spacing: -0.02em;
}

.result-tagline {
  font-size: 0.95rem;
  color: var(--text-secondary);
  font-style: italic;
  line-height: 1.5;
}

.result-icon-wrap {
  display: flex;
  justify-content: center;
  padding: 28px 24px;
}

.result-icon {
  width: 120px;
  height: 120px;
  color: var(--type-color);
  opacity: 0.85;
  animation: iconFloat 3s ease-in-out infinite;
}

.result-icon svg {
  width: 100%;
  height: 100%;
}

@keyframes iconFloat {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-6px); }
}

.result-desc {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.75;
  padding: 0 24px 28px;
  border-bottom: 1px solid var(--border);
}

.result-relations {
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  border-bottom: 1px solid var(--border);
}

.relation-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.relation-label {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
}

.relation-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag {
  display: inline-block;
  font-size: 0.82rem;
  font-weight: 500;
  padding: 6px 12px;
  border-radius: 100px;
  border: 1px solid var(--border);
}

.tag-partner {
  background: rgba(29, 184, 142, 0.1);
  border-color: rgba(29, 184, 142, 0.25);
  color: #4dcca8;
}

.tag-rival {
  background: rgba(255, 77, 46, 0.1);
  border-color: rgba(255, 77, 46, 0.25);
  color: #ff7a5c;
}

.result-dimensions {
  padding: 24px;
}

.section-title {
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 18px;
}

.dim-row {
  margin-bottom: 16px;
}

.dim-row:last-child { margin-bottom: 0; }

.dim-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 6px;
}

.dim-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.dim-result {
  font-size: 0.85rem;
  font-weight: 600;
}

.dim-track {
  height: 6px;
  background: var(--bg-elevated);
  border-radius: 100px;
  overflow: hidden;
}

.dim-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--type-color), color-mix(in srgb, var(--type-color) 60%, white));
  border-radius: 100px;
  transition: width 0.8s cubic-bezier(0.4, 0, 0.2, 1);
  width: 0;
}

.dim-score {
  font-size: 0.72rem;
  color: var(--text-muted);
  margin-top: 4px;
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.result-actions {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 24px;
}

.result-actions .btn-ghost { margin-top: 0; }

/* ── Responsive ── */
@media (min-width: 480px) {
  .app { padding: 40px 24px calc(48px + var(--safe-bottom)); }
  .hero { padding: 64px 0 48px; }
  .question-card { padding: 32px 28px; }
  .option-btn { padding: 18px 20px; font-size: 1rem; }
}

@media (max-width: 380px) {
  .dimension-preview { grid-template-columns: 1fr; }
  .option-btn { padding: 14px 14px; gap: 10px; }
  .option-letter { width: 26px; height: 26px; font-size: 0.75rem; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}