/* uyên.ai — landing. Dark cockpit identity, cyan accent, zero JS. */

:root {
  --bg-top: #0d1424;
  --bg-bottom: #020306;
  --accent: #00d8ff;
  --accent-soft: rgba(0, 216, 255, 0.12);
  --text: #f2f6fa;
  --muted: #93a0b4;
  --card: rgba(255, 255, 255, 0.05);
  --card-border: rgba(255, 255, 255, 0.09);
  --radius: 18px;
  --font: "Be Vietnam Pro", -apple-system, BlinkMacSystemFont, "Segoe UI",
    Roboto, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: linear-gradient(180deg, var(--bg-top) 0%, var(--bg-bottom) 55%) fixed,
    var(--bg-bottom);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
.container { max-width: 1100px; margin: 0 auto; padding: 0 22px; }
a { color: var(--accent); text-decoration: none; }
img { max-width: 100%; display: block; }
h1, h2, h3 { line-height: 1.2; text-wrap: balance; }
h2 { font-size: clamp(1.6rem, 3.4vw, 2.2rem); font-weight: 800; letter-spacing: -0.02em; margin: 0 0 26px; }
section { padding: 64px 0; }

/* ─ Nav ─ */
nav { display: flex; align-items: center; gap: 26px; padding: 18px 0; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 1.15rem; color: var(--text); }
.brand img { width: 34px; height: 34px; border-radius: 8px; }
.brand .ai { color: var(--accent); }
nav .links { display: flex; gap: 20px; margin-left: auto; }
nav .links a { color: var(--muted); font-weight: 500; font-size: 0.95rem; transition: color 0.15s; }
nav .links a:hover { color: var(--text); }
.nav-right { display: flex; align-items: center; gap: 14px; }
.lang { display: flex; gap: 2px; background: var(--card); border: 1px solid var(--card-border); border-radius: 999px; padding: 3px; }
.lang a { color: var(--muted); font-size: 0.8rem; font-weight: 700; padding: 3px 10px; border-radius: 999px; }
.lang a.active { background: var(--accent); color: #012; }
.nav-cta {
  font-weight: 700; font-size: 0.9rem; color: #012;
  background: var(--accent); padding: 8px 16px; border-radius: 999px;
  transition: transform 0.15s, box-shadow 0.15s;
}
.nav-cta:hover { transform: translateY(-1px); box-shadow: 0 6px 22px rgba(0, 216, 255, 0.35); }

/* ─ Hero ─ */
.hero {
  display: grid; grid-template-columns: 1.15fr 0.85fr; align-items: center;
  gap: 48px; padding: 64px 0 40px;
}
.eyebrow {
  display: inline-block; font-size: 0.82rem; font-weight: 600; color: var(--accent);
  background: var(--accent-soft); border: 1px solid rgba(0, 216, 255, 0.25);
  padding: 5px 14px; border-radius: 999px; margin: 0 0 18px;
}
.hero h1 {
  font-size: clamp(2.2rem, 5vw, 3.4rem); font-weight: 800;
  letter-spacing: -0.03em; margin: 0 0 18px;
}
.hero .sub { color: var(--muted); font-size: 1.08rem; max-width: 34em; margin: 0 0 28px; }
.cta-row { display: flex; align-items: center; gap: 16px; flex-wrap: wrap; }
.cta {
  display: inline-flex; align-items: center; gap: 12px;
  background: var(--accent); color: #012; border-radius: 14px;
  padding: 10px 22px; font-weight: 700;
  box-shadow: 0 10px 34px rgba(0, 216, 255, 0.28);
  transition: transform 0.15s, box-shadow 0.15s;
}
.cta:hover { transform: translateY(-2px); box-shadow: 0 14px 44px rgba(0, 216, 255, 0.4); }
.cta svg { width: 26px; height: 26px; }
.cta span { display: flex; flex-direction: column; line-height: 1.15; text-align: left; }
.cta small { font-size: 0.72rem; font-weight: 600; opacity: 0.75; }
.cta strong { font-size: 1.1rem; letter-spacing: -0.01em; }
.cta-ghost {
  color: var(--text); font-weight: 600; padding: 12px 20px;
  border: 1px solid var(--card-border); border-radius: 14px;
  transition: border-color 0.15s, background 0.15s;
}
.cta-ghost:hover { border-color: var(--accent); background: var(--accent-soft); }

/* Phone frame */
.hero-phone { display: flex; justify-content: center; }
.phone {
  width: min(310px, 78vw); border-radius: 44px; padding: 10px;
  background: #10141c; border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.55), 0 0 60px rgba(0, 216, 255, 0.08);
  position: relative;
}
.phone::before {
  content: ""; position: absolute; top: 20px; left: 50%; transform: translateX(-50%);
  width: 86px; height: 24px; background: #10141c; border-radius: 999px; z-index: 2;
}
.phone img { border-radius: 34px; width: 100%; height: auto; }
.phone-sm { width: 230px; flex: none; }

@media (prefers-reduced-motion: no-preference) {
  .hero-copy, .hero-phone { animation: rise 0.7s ease both; }
  .hero-phone { animation-delay: 0.12s; }
  @keyframes rise { from { opacity: 0; transform: translateY(16px); } }
}

/* ─ ADAS showcase ─ */
.adas { text-align: center; }
.adas-caption { color: var(--muted); max-width: 44em; margin: -10px auto 30px; }
.phone-land {
  max-width: 880px; margin: 0 auto; border-radius: 34px; padding: 9px;
  background: #10141c; border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.55), 0 0 60px rgba(0, 216, 255, 0.08);
}
.phone-land img { border-radius: 26px; width: 100%; height: auto; }

/* ─ Stats ─ */
.stats {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px;
  padding: 26px 0 10px;
}
.stat {
  background: var(--card); border: 1px solid var(--card-border);
  border-radius: var(--radius); padding: 18px 20px; text-align: center;
}
.stat strong { display: block; font-size: 1.5rem; font-weight: 800; color: var(--accent); letter-spacing: -0.02em; }
.stat span { font-size: 0.85rem; color: var(--muted); }

/* ─ Features ─ */
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 18px; }
.card {
  background: var(--card); border: 1px solid var(--card-border);
  border-radius: var(--radius); padding: 26px;
  transition: transform 0.18s, border-color 0.18s, background 0.18s;
}
.card:hover { transform: translateY(-4px); border-color: rgba(0, 216, 255, 0.35); background: rgba(255, 255, 255, 0.07); }
.card-icon {
  width: 46px; height: 46px; border-radius: 13px; color: var(--accent);
  background: var(--accent-soft); border: 1px solid rgba(0, 216, 255, 0.25);
  display: flex; align-items: center; justify-content: center; margin-bottom: 16px;
}
.card-icon svg { width: 24px; height: 24px; }
.card h3 { margin: 0 0 8px; font-size: 1.06rem; font-weight: 700; }
.card p { margin: 0; color: var(--muted); font-size: 0.95rem; }

/* ─ How it works ─ */
.steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.steps li {
  display: flex; gap: 16px; align-items: flex-start;
  background: var(--card); border: 1px solid var(--card-border);
  border-radius: var(--radius); padding: 24px;
}
.step-n {
  flex: none; width: 34px; height: 34px; border-radius: 50%;
  background: var(--accent); color: #012; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
}
.steps h3 { margin: 4px 0 6px; font-size: 1.02rem; }
.steps p { margin: 0; color: var(--muted); font-size: 0.92rem; }

/* ─ Screenshots ─ */
.shots {
  display: flex; gap: 26px; justify-content: center; flex-wrap: wrap;
}

/* ─ FAQ ─ */
.faq-list { max-width: 760px; }
.faq-list details {
  background: var(--card); border: 1px solid var(--card-border);
  border-radius: 14px; padding: 4px 22px; margin-bottom: 12px;
}
.faq-list summary {
  cursor: pointer; font-weight: 700; padding: 14px 0; list-style: none;
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
}
.faq-list summary::after { content: "+"; color: var(--accent); font-size: 1.3rem; font-weight: 400; }
.faq-list details[open] summary::after { content: "–"; }
.faq-list p { margin: 0 0 16px; color: var(--muted); font-size: 0.95rem; }

/* ─ Safety ─ */
.safety {
  border: 1px solid rgba(255, 190, 80, 0.35); background: rgba(255, 190, 80, 0.07);
  border-radius: var(--radius); padding: 30px; margin: 20px 0;
}
.safety h2 { color: #ffcf7d; font-size: 1.2rem; margin-bottom: 10px; }
.safety p { margin: 0; color: var(--muted); font-size: 0.95rem; }

/* ─ Final CTA ─ */
.final-cta { text-align: center; padding: 80px 0 90px; }
.final-cta h2 { font-size: 2.4rem; margin-bottom: 6px; }
.final-cta .ai { color: var(--accent); }
.final-cta p { color: var(--muted); margin: 0 0 26px; }

/* ─ Footer ─ */
footer { border-top: 1px solid var(--card-border); padding: 44px 0 34px; }
.foot-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 26px; }
.foot-brand p { color: var(--muted); font-size: 0.9rem; max-width: 24em; }
.foot-col h4 { margin: 4px 0 12px; font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); }
.foot-col a { display: block; color: var(--text); font-size: 0.93rem; padding: 4px 0; opacity: 0.85; }
.foot-col a:hover { color: var(--accent); opacity: 1; }
.foot-copy { margin-top: 30px; color: var(--muted); font-size: 0.85rem; }

/* ─ Auth / account forms ─ */
.nav-login { color: var(--muted); font-weight: 600; font-size: 0.9rem; }
.nav-login:hover { color: var(--text); }
.form-card {
  max-width: 460px; margin: 48px auto; padding: 30px;
  background: var(--card); border: 1px solid var(--card-border);
  border-radius: var(--radius);
}
.form-card h1, .form-card h2 { font-size: 1.4rem; margin: 0 0 12px; }
.form-intro { color: var(--muted); font-size: 0.95rem; margin: 0 0 20px; }
.form-card label { display: block; font-size: 0.85rem; font-weight: 600; margin: 0 0 6px; }
.form-card input[type="email"], .form-card input[type="text"] {
  width: 100%; padding: 12px 14px; margin-bottom: 16px;
  background: rgba(255, 255, 255, 0.06); border: 1px solid var(--card-border);
  border-radius: 12px; color: var(--text); font-size: 1rem; font-family: var(--font);
}
.form-card input:focus { outline: 2px solid var(--accent); border-color: transparent; }
.form-card button {
  width: 100%; padding: 13px; border: 0; border-radius: 12px;
  background: var(--accent); color: #012; font-weight: 700; font-size: 1rem;
  font-family: var(--font); cursor: pointer;
}
.form-card button:hover { filter: brightness(1.08); }
.form-error {
  background: rgba(255, 90, 90, 0.12); border: 1px solid rgba(255, 90, 90, 0.4);
  color: #ff9d9d; border-radius: 10px; padding: 10px 14px; font-size: 0.9rem;
}
.form-hint { color: var(--muted); font-size: 0.85rem; margin-top: 14px; }
.account-facts { margin: 0 0 22px; }
.account-facts dt { color: var(--muted); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.06em; margin-top: 14px; }
.account-facts dd { margin: 4px 0 0; font-size: 1.02rem; }
.account-facts .tier { text-transform: capitalize; }
.chip {
  display: inline-block; padding: 3px 12px; margin-right: 6px;
  background: var(--accent-soft); border: 1px solid rgba(0, 216, 255, 0.3);
  border-radius: 999px; font-size: 0.85rem; text-transform: capitalize;
}
.btn-secondary { background: rgba(255, 255, 255, 0.1) !important; color: var(--text) !important; }
.danger-zone { border-color: rgba(255, 90, 90, 0.35); }
.danger-zone h2 { color: #ff9d9d; }
.confirm-row {
  display: flex !important; gap: 10px; align-items: flex-start;
  font-weight: 500 !important; font-size: 0.92rem !important;
  color: var(--muted); margin-bottom: 16px !important;
}
.confirm-row input { width: auto; margin-top: 3px; }
.btn-danger { background: #e5484d !important; color: #fff !important; }

/* ─ Legal pages ─ */
.legal { max-width: 760px; padding: 40px 0 70px; }
.legal h1 { font-size: 2rem; letter-spacing: -0.02em; }
.legal h2 { font-size: 1.25rem; margin-top: 34px; }
.legal p, .legal li { color: var(--muted); }
.legal .effective { color: var(--muted); font-size: 0.9rem; }

/* ─ Responsive ─ */
@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; text-align: center; padding-top: 36px; }
  .hero .sub { margin-left: auto; margin-right: auto; }
  .cta-row { justify-content: center; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: 1fr; }
  .foot-grid { grid-template-columns: 1fr 1fr; }
  nav .links { display: none; }
}
@media (max-width: 640px) {
  .shots {
    justify-content: flex-start; flex-wrap: nowrap; overflow-x: auto;
    scroll-snap-type: x mandatory; padding-bottom: 14px; margin: 0 -22px; padding-left: 22px;
  }
  .shots .phone-sm { scroll-snap-align: center; }
  .nav-cta { display: none; }
}