:root {
  --bg-1: #f1f5f9;
  --bg-2: #ffffff;
  --bg-3: #e2e8f0;
  --bg-4: #cbd5e1;
  --accent: #6366f1;
  --accent-soft: #818cf8;
  --accent-dim: rgba(99, 102, 241, 0.07);
  --accent-glow: rgba(99, 102, 241, 0.04);
  --text-1: #1e293b;
  --text-2: #475569;
  --text-3: #94a3b8;
  --text-4: #cbd5e1;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.06);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.08);
  --serif: 'Noto Serif SC', 'Songti SC', serif;
  --sans: 'DM Sans', -apple-system, 'PingFang SC', sans-serif;
  --ease: cubic-bezier(0.23, 1, 0.32, 1);
}

* { margin: 0; padding: 0; box-sizing: border-box; -webkit-tap-highlight-color: transparent; }

body {
  font-family: var(--sans);
  background: var(--bg-1);
  color: var(--text-1);
  min-height: 100vh;
  min-height: 100dvh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* PAGE SYSTEM */
.page {
  display: none;
  min-height: 100vh;
  min-height: 100dvh;
  flex-direction: column;
  align-items: center;
}
.page.active {
  display: flex;
  animation: pageIn 0.6s var(--ease);
}
@keyframes pageIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* START PAGE */
.start-page {
  justify-content: center;
  padding: 40px 24px;
  background: linear-gradient(180deg, #eef2ff 0%, var(--bg-1) 50%);
  position: relative;
  overflow: hidden;
}

.start-particles {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

.start-particles span {
  position: absolute;
  width: 2px;
  height: 2px;
  background: rgba(99, 102, 241, 0.25);
  border-radius: 50%;
  animation: particleDrift linear infinite;
}

@keyframes particleDrift {
  0% { transform: translateY(0) scale(1); opacity: 0; }
  10% { opacity: 1; }
  90% { opacity: 1; }
  100% { transform: translateY(-100vh) scale(0); opacity: 0; }
}

.hero-visual {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  position: relative;
  margin-bottom: 20px;
}

.start-logo {
  position: relative;
  width: 90px;
  height: 90px;
  animation: logoFloat 4s ease-in-out infinite;
}

.start-logo svg {
  width: 100%;
  height: 100%;
}

@keyframes logoFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

.logo-ring-outer {
  animation: logoSpin 20s linear infinite;
  transform-origin: 45px 45px;
}

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

.start-content {
  width: 100%;
  padding: 0;
  position: relative;
  z-index: 1;
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.start-divider {
  width: 40px;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  margin-bottom: 28px;
  border-radius: 1px;
}

.start-title {
  font-family: var(--serif);
  font-size: 28px;
  font-weight: 700;
  color: var(--text-1);
  line-height: 1.4;
  margin-bottom: 12px;
  letter-spacing: 1px;
}

.start-desc {
  font-size: 14px;
  color: var(--text-3);
  line-height: 1.7;
  margin-bottom: 36px;
}

.start-pills {
  display: flex;
  gap: 8px;
  margin-bottom: 40px;
  flex-wrap: wrap;
  justify-content: center;
}

.start-pill {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 20px;
  background: var(--bg-2);
  border: 1px solid var(--bg-3);
  box-shadow: var(--shadow-sm);
}

.start-pill svg {
  width: 14px;
  height: 14px;
  stroke: var(--accent);
  fill: none;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.start-pill span {
  font-size: 12px;
  color: var(--text-2);
  letter-spacing: 0.3px;
}

.btn-start {
  width: 100%;
  max-width: 300px;
  height: 56px;
  background: linear-gradient(135deg, #818cf8, #6366f1);
  border: none;
  border-radius: 16px;
  color: #fff;
  font-family: var(--sans);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 1px;
  cursor: pointer;
  transition: transform 0.2s var(--ease), box-shadow 0.2s;
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.btn-start:active {
  transform: scale(0.97);
  box-shadow: 0 2px 12px rgba(99, 102, 241, 0.35);
}

.btn-start svg {
  width: 18px;
  height: 18px;
  stroke: #fff;
  fill: none;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.start-meta {
  text-align: center;
  margin-top: 24px;
  font-size: 11px;
  color: var(--text-3);
  letter-spacing: 2px;
}

/* QUESTION PAGE */
.question-page {
  background: var(--bg-1);
  padding: 0;
  justify-content: flex-start;
  position: relative;
  overflow: hidden;
}

.question-page .q-particles {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

.question-page .q-particles span {
  position: absolute;
  width: 2px;
  height: 2px;
  background: rgba(99, 102, 241, 0.18);
  border-radius: 50%;
  animation: particleDrift linear infinite;
}

.q-top {
  position: relative;
  z-index: 1;
  width: 100%;
  padding: 16px 20px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-shrink: 0;
}

.q-back {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: var(--bg-2);
  border: 1px solid var(--bg-3);
  box-shadow: var(--shadow-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.2s;
}

.q-back:active { background: var(--bg-3); }

.q-back svg {
  width: 18px;
  height: 18px;
  stroke: var(--accent);
  fill: none;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.q-step {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 600;
  color: var(--text-3);
}

.q-step b {
  color: var(--accent);
  font-weight: 700;
  font-size: 15px;
}

.q-spacer { width: 40px; }

.q-progress {
  position: relative;
  z-index: 1;
  width: 100%;
  padding: 16px 20px 0;
  flex-shrink: 0;
}

.q-progress-track {
  width: 100%;
  height: 4px;
  background: var(--bg-3);
  border-radius: 2px;
  overflow: hidden;
}

.q-progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--accent-soft));
  border-radius: 2px;
  transition: width 0.5s var(--ease);
}

.q-body {
  flex: 1;
  width: 100%;
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.q-section-tag {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 10px;
  background: rgba(99, 102, 241, 0.08);
  border: 1px solid rgba(99, 102, 241, 0.12);
  font-size: 11px;
  color: var(--accent);
  font-weight: 600;
  letter-spacing: 1px;
  margin: 0 auto 14px;
  text-align: center;
}

.q-text {
  font-family: var(--serif);
  font-size: 22px;
  font-weight: 600;
  color: var(--text-1);
  line-height: 1.6;
  margin-bottom: 32px;
  text-align: center;
}

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

.opt-btn {
  position: relative;
  width: 100%;
  padding: 16px 18px;
  background: var(--bg-2);
  border: 1px solid var(--bg-3);
  border-radius: 14px;
  color: var(--text-2);
  font-family: var(--sans);
  font-size: 15px;
  text-align: left;
  cursor: pointer;
  transition: all 0.25s var(--ease);
  line-height: 1.5;
  display: flex;
  align-items: center;
  gap: 14px;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.opt-btn:active {
  transform: scale(0.98);
  border-color: var(--accent-soft);
  box-shadow: 0 2px 8px rgba(99, 102, 241, 0.12);
}

.opt-btn.selected {
  border-color: var(--accent);
  background: rgba(99, 102, 241, 0.05);
  box-shadow: 0 2px 12px rgba(99, 102, 241, 0.15);
}

.opt-idx {
  width: 28px;
  height: 28px;
  border-radius: 9px;
  background: var(--bg-1);
  border: 1px solid var(--bg-3);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 12px;
  color: var(--accent);
  flex-shrink: 0;
  transition: all 0.25s;
}

.opt-btn.selected .opt-idx {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

/* LOADING PAGE */
.loading-page {
  background: var(--bg-1);
  justify-content: center;
  padding: 40px 24px;
  text-align: center;
}

.loader {
  position: relative;
  width: 80px;
  height: 80px;
  margin: 0 auto 32px;
}

.loader-ring {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 2px solid var(--bg-3);
}

.loader-arc {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 2px solid transparent;
  border-top-color: var(--accent);
  animation: loaderSpin 1.2s linear infinite;
}

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

.loader-dot {
  position: absolute;
  top: -3px;
  left: 50%;
  transform: translateX(-50%);
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  animation: loaderSpin 1.2s linear infinite;
  transform-origin: 3px 43px;
}

.loader-text {
  font-family: var(--serif);
  font-size: 16px;
  color: var(--text-2);
  margin-bottom: 6px;
}

.loader-sub {
  font-size: 12px;
  color: var(--text-3);
  letter-spacing: 1px;
}

/* RESULT PAGE */
.result-page {
  background: linear-gradient(180deg, #eef2ff 0%, var(--bg-1) 30%);
  padding: 40px 20px 48px;
  justify-content: flex-start;
}

.r-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 3px;
  margin-bottom: 20px;
}

.r-card {
  width: 100%;
  max-width: 360px;
  background: var(--bg-2);
  border: 1px solid var(--bg-3);
  border-radius: 24px;
  padding: 32px 24px 28px;
  position: relative;
  overflow: hidden;
  margin-bottom: 20px;
  box-shadow: var(--shadow-lg);
}

.r-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 10%;
  right: 10%;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  border-radius: 1px;
}
.r-card::after {
  display: none;
  pointer-events: none;
}

/* Brand Logo */
.r-brand-logo {
  width: 88px;
  height: 88px;
  border-radius: 50%;
  background: linear-gradient(135deg, #eef2ff, #e0e7ff);
  border: 1px solid rgba(99, 102, 241, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
  box-shadow: 0 2px 12px rgba(99, 102, 241, 0.08);
}

.r-brand-logo svg {
  width: 48px;
  height: 48px;
}

.r-icon-wrap {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--accent-dim);
  border: 1px solid rgba(99, 102, 241, 0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 14px;
}

.r-icon-wrap svg {
  width: 22px;
  height: 22px;
  stroke: var(--accent);
  fill: none;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.r-type {
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: 2px;
  text-align: center;
  margin-bottom: 10px;
}

.r-car {
  font-family: var(--serif);
  font-size: 26px;
  font-weight: 700;
  color: var(--text-1);
  text-align: center;
  margin-bottom: 4px;
}

.r-brand {
  font-size: 13px;
  color: var(--text-3);
  text-align: center;
  margin-bottom: 20px;
}

.r-specs {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 1px;
  background: var(--bg-3);
  border-radius: 14px;
  overflow: hidden;
  margin-bottom: 20px;
}

.r-spec {
  background: var(--bg-1);
  padding: 14px 8px;
  text-align: center;
}

.r-spec-val {
  font-family: var(--sans);
  font-size: 16px;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 4px;
}

.r-spec-lbl {
  font-size: 10px;
  color: var(--text-3);
  letter-spacing: 0.5px;
}

.r-slogan {
  font-family: var(--serif);
  font-size: 14px;
  color: var(--text-3);
  text-align: center;
  line-height: 1.6;
  margin-bottom: 16px;
  font-style: italic;
}

.r-portrait {
  font-size: 13px;
  color: var(--accent);
  text-align: center;
  line-height: 1.6;
  margin-bottom: 16px;
  padding: 10px 16px;
  background: rgba(99, 102, 241, 0.05);
  border-radius: 12px;
  border: 1px solid rgba(99, 102, 241, 0.1);
}

.r-desc {
  font-size: 14px;
  color: var(--text-2);
  line-height: 1.8;
  text-align: left;
}

.r-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 20px;
  justify-content: center;
}

.r-tag {
  padding: 5px 12px;
  border-radius: 8px;
  background: var(--bg-1);
  border: 1px solid var(--bg-3);
  font-size: 11px;
  color: var(--accent);
  font-weight: 500;
}

.r-more-section {
  width: 100%;
  max-width: 360px;
  margin-bottom: 28px;
}

.r-more-title {
  font-size: 12px;
  color: var(--text-3);
  letter-spacing: 2px;
  font-weight: 600;
  margin-bottom: 12px;
}

.r-more-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.r-alt {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 16px;
  background: var(--bg-2);
  border: 1px solid var(--bg-3);
  border-radius: 14px;
  box-shadow: var(--shadow-sm);
}

.r-alt-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.r-alt-logo {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: linear-gradient(135deg, #eef2ff, #e0e7ff);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.r-alt-logo svg {
  width: 20px;
  height: 20px;
}

.r-alt-name {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-1);
}

.r-alt-info {
  font-size: 11px;
  color: var(--text-3);
  margin-top: 2px;
}

.r-alt-price {
  font-size: 14px;
  font-weight: 700;
  color: var(--accent);
  white-space: nowrap;
}

.btn-again {
  width: 100%;
  max-width: 360px;
  height: 50px;
  background: var(--bg-2);
  border: 1px solid var(--bg-3);
  border-radius: 14px;
  color: var(--text-2);
  font-family: var(--sans);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  letter-spacing: 0.5px;
  box-shadow: var(--shadow-sm);
}

.btn-again:active {
  background: var(--bg-1);
  border-color: var(--accent-soft);
  transform: scale(0.98);
}