/* 驾考 APP 官网 — 主样式 */
:root {
  --bg: #0c1222;
  --bg-soft: #121a2e;
  --surface: rgba(255, 255, 255, 0.06);
  --surface-hover: rgba(255, 255, 255, 0.1);
  --border: rgba(255, 255, 255, 0.08);
  --text: #f0f4fc;
  --muted: #94a3b8;
  --accent: #22c55e;
  --accent-dim: #16a34a;
  --blue: #38bdf8;
  --radius: 14px;
  --radius-lg: 22px;
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.45);
  --font: "DM Sans", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  min-height: 100vh;
}

a {
  color: inherit;
  text-decoration: none;
}

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

/* 背景纹理 */
.bg-grid {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 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% 0%, black 20%, transparent 70%);
}

.bg-glow {
  position: fixed;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  filter: blur(120px);
  opacity: 0.35;
  pointer-events: none;
  z-index: 0;
}

.bg-glow--1 {
  top: -200px;
  right: -100px;
  background: #1d4ed8;
}

.bg-glow--2 {
  bottom: 10%;
  left: -150px;
  background: var(--accent);
  opacity: 0.2;
}

.wrap {
  position: relative;
  z-index: 1;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

/* 顶栏 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(16px);
  background: rgba(12, 18, 34, 0.75);
  border-bottom: 1px solid var(--border);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1120px;
  margin: 0 auto;
  padding: 14px 24px;
  gap: 24px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
}

.logo__mark {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--accent), #15803d);
  display: grid;
  place-items: center;
  font-size: 1.25rem;
  box-shadow: 0 8px 24px rgba(34, 197, 94, 0.35);
}

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

.nav a {
  padding: 8px 14px;
  border-radius: 10px;
  color: var(--muted);
  font-size: 0.95rem;
  transition: color 0.2s, background 0.2s;
}

.nav a:hover {
  color: var(--text);
  background: var(--surface);
}

.nav__toggle {
  display: none;
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 10px 12px;
  border-radius: 10px;
  cursor: pointer;
  font-size: 1.1rem;
}

@media (max-width: 768px) {
  .nav {
    position: fixed;
    inset: 64px 16px auto 16px;
    flex-direction: column;
    align-items: stretch;
    padding: 12px;
    background: var(--bg-soft);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity 0.2s, transform 0.2s, visibility 0.2s;
  }

  .nav.is-open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .nav__toggle {
    display: block;
  }
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 12px;
  font-weight: 600;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.2s, background 0.2s;
}

.btn:active {
  transform: scale(0.98);
}

.btn--primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-dim));
  color: #052e16;
  box-shadow: 0 8px 28px rgba(34, 197, 94, 0.35);
}

.btn--primary:hover {
  box-shadow: 0 12px 36px rgba(34, 197, 94, 0.45);
}

.btn--ghost {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
}

.btn--ghost:hover {
  background: var(--surface-hover);
}

/* Hero */
.hero {
  padding: 72px 0 96px;
}

.hero__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

@media (max-width: 900px) {
  .hero__grid {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero__actions {
    justify-content: center;
  }

  .hero__badges {
    justify-content: center;
  }
}

.hero__eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--blue);
  margin-bottom: 16px;
}

.hero h1 {
  margin: 0 0 16px;
  font-size: clamp(2rem, 4.5vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
}

.hero__lead {
  margin: 0 0 28px;
  font-size: 1.1rem;
  color: var(--muted);
  max-width: 32em;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 24px;
}

.hero__badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.badge {
  font-size: 0.85rem;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--muted);
}

/* 手机 mock */
.phone-mock {
  justify-self: end;
  width: min(100%, 300px);
  aspect-ratio: 9 / 18.5;
  border-radius: 36px;
  padding: 12px;
  background: linear-gradient(160deg, #1e293b, #0f172a);
  box-shadow: var(--shadow), inset 0 0 0 1px rgba(255, 255, 255, 0.08);
  position: relative;
}

@media (max-width: 900px) {
  .phone-mock {
    justify-self: center;
    margin-top: 16px;
  }
}

.phone-mock__screen {
  border-radius: 26px;
  height: 100%;
  background: linear-gradient(180deg, #0f172a 0%, #1e3a5f 50%, #0c4a6e 100%);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.phone-mock__notch {
  height: 24px;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  padding-bottom: 6px;
}

.phone-mock__notch span {
  width: 80px;
  height: 22px;
  background: #0f172a;
  border-radius: 12px;
}

.phone-mock__content {
  flex: 1;
  padding: 16px 18px 24px;
}

.phone-mock__card {
  background: rgba(255, 255, 255, 0.08);
  border-radius: 14px;
  padding: 14px;
  margin-bottom: 12px;
  border: 1px solid rgba(255, 255, 255, 0.06);
}

.phone-mock__q {
  font-size: 0.85rem;
  color: #e2e8f0;
  margin-bottom: 10px;
  line-height: 1.45;
}

.phone-mock__opts {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.phone-mock__opt {
  font-size: 0.75rem;
  padding: 8px 10px;
  border-radius: 8px;
  background: rgba(0, 0, 0, 0.25);
  color: #cbd5e1;
}

.phone-mock__opt--ok {
  background: rgba(34, 197, 94, 0.25);
  color: #86efac;
  border: 1px solid rgba(34, 197, 94, 0.4);
}

.phone-mock__bar {
  margin-top: auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.7rem;
  color: #94a3b8;
}

/* Section 通用 */
.section {
  padding: 72px 0;
}

.section--alt {
  background: rgba(255, 255, 255, 0.02);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.section__title {
  text-align: center;
  margin: 0 0 12px;
  font-size: clamp(1.6rem, 3vw, 2rem);
  font-weight: 800;
  letter-spacing: -0.02em;
}

.section__subtitle {
  text-align: center;
  margin: 0 auto 48px;
  max-width: 520px;
  color: var(--muted);
  font-size: 1.05rem;
}

/* Features */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

@media (max-width: 768px) {
  .feature-grid {
    grid-template-columns: 1fr;
  }
}

.feature-card {
  padding: 24px;
  border-radius: var(--radius-lg);
  background: var(--surface);
  border: 1px solid var(--border);
  transition: border-color 0.2s, transform 0.2s;
}

.feature-card:hover {
  border-color: rgba(56, 189, 248, 0.35);
  transform: translateY(-2px);
}

.feature-card__icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: grid;
  place-items: center;
  font-size: 1.35rem;
  margin-bottom: 16px;
  background: rgba(56, 189, 248, 0.12);
}

.feature-card h3 {
  margin: 0 0 8px;
  font-size: 1.1rem;
}

.feature-card p {
  margin: 0;
  font-size: 0.95rem;
  color: var(--muted);
}

/* Steps */
.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  counter-reset: step;
}

@media (max-width: 900px) {
  .steps {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 480px) {
  .steps {
    grid-template-columns: 1fr;
  }
}

.step {
  padding: 20px;
  border-radius: var(--radius);
  background: var(--surface);
  border: 1px solid var(--border);
  position: relative;
}

.step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  top: 16px;
  right: 16px;
  width: 28px;
  height: 28px;
  border-radius: 8px;
  background: rgba(34, 197, 94, 0.2);
  color: var(--accent);
  font-weight: 700;
  font-size: 0.85rem;
  display: grid;
  place-items: center;
}

.step h3 {
  margin: 0 0 8px;
  font-size: 1rem;
  padding-right: 36px;
}

.step p {
  margin: 0;
  font-size: 0.9rem;
  color: var(--muted);
}

/* Download */
.download-panel {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 32px;
  align-items: center;
  padding: 40px;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, rgba(34, 197, 94, 0.12), rgba(56, 189, 248, 0.08));
  border: 1px solid rgba(34, 197, 94, 0.25);
}

@media (max-width: 768px) {
  .download-panel {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .download-panel__qr {
    justify-self: center;
  }
}

.download-panel h2 {
  margin: 0 0 12px;
  font-size: 1.5rem;
}

.download-panel p {
  margin: 0 0 20px;
  color: var(--muted);
}

.download-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.download-panel__qr {
  width: 120px;
  height: 120px;
  border-radius: 12px;
  background: white;
  padding: 8px;
  display: grid;
  place-items: center;
}

.download-panel__qr svg {
  width: 100%;
  height: 100%;
}

/* FAQ */
.faq-list {
  max-width: 720px;
  margin: 0 auto;
}

details.faq-item {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 10px;
  background: var(--surface);
  overflow: hidden;
}

details.faq-item summary {
  padding: 18px 20px;
  cursor: pointer;
  font-weight: 600;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

details.faq-item summary::-webkit-details-marker {
  display: none;
}

details.faq-item summary::after {
  content: "+";
  font-size: 1.25rem;
  color: var(--muted);
  transition: transform 0.2s;
}

details.faq-item[open] summary::after {
  transform: rotate(45deg);
}

details.faq-item .faq-item__body {
  padding: 0 20px 18px;
  color: var(--muted);
  font-size: 0.95rem;
  border-top: 1px solid var(--border);
  margin: 0;
  padding-top: 14px;
}

/* Footer */
.site-footer {
  padding: 48px 0 32px;
  border-top: 1px solid var(--border);
  margin-top: 24px;
}

.site-footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 32px;
  margin-bottom: 40px;
}

@media (max-width: 768px) {
  .site-footer__grid {
    grid-template-columns: 1fr;
  }
}

.site-footer .logo {
  margin-bottom: 12px;
}

.site-footer__desc {
  color: var(--muted);
  font-size: 0.9rem;
  max-width: 320px;
  margin: 0;
}

.site-footer h4 {
  margin: 0 0 14px;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.site-footer ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-footer li {
  margin-bottom: 10px;
}

.site-footer a {
  color: var(--muted);
  font-size: 0.95rem;
}

.site-footer a:hover {
  color: var(--text);
}

.site-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 16px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
  color: var(--muted);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}