/* huongdanhosonoxh.vn — Rai Holdings brand styles v1 */
:root {
  --c-bg: #f8fafc;
  --c-surface: #ffffff;
  --c-text: #0f172a;
  --c-text-soft: #475569;
  --c-text-mute: #64748b;
  --c-border: #e2e8f0;
  --c-primary: #0d4ea2;            /* deep blue — uy tín, nhà nước */
  --c-primary-dark: #093878;
  --c-accent: #f59e0b;              /* amber — call to action */
  --c-success: #16a34a;
  --shadow-sm: 0 1px 2px rgba(15,23,42,.06), 0 1px 3px rgba(15,23,42,.08);
  --shadow-md: 0 4px 6px -1px rgba(15,23,42,.08), 0 2px 4px -2px rgba(15,23,42,.06);
  --radius: 10px;
  --radius-lg: 16px;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Inter", "Helvetica Neue", Arial, sans-serif;
  color: var(--c-text);
  background: var(--c-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ─────── TOPBAR ─────── */
.topbar {
  background: var(--c-surface);
  border-bottom: 1px solid var(--c-border);
  position: sticky; top: 0; z-index: 50;
}
.topbar-inner {
  display: flex; justify-content: space-between; align-items: center;
  height: 64px;
}
.brand {
  display: flex; align-items: center; gap: 10px;
  text-decoration: none; color: var(--c-text); font-weight: 700; font-size: 17px;
}
.brand-dot {
  width: 12px; height: 12px; border-radius: 50%;
  background: linear-gradient(135deg, var(--c-primary), var(--c-accent));
}
.brand-tld { color: var(--c-text-mute); font-weight: 500; }
.topnav { display: flex; gap: 28px; }
.topnav a {
  color: var(--c-text-soft); text-decoration: none; font-size: 15px; font-weight: 500;
  transition: color .15s;
}
.topnav a:hover { color: var(--c-primary); }

@media (max-width: 640px) {
  .topnav { display: none; }
}

/* ─────── HERO ─────── */
.hero {
  background: linear-gradient(180deg, #eff6ff 0%, var(--c-bg) 100%);
  padding: 80px 0 64px;
  border-bottom: 1px solid var(--c-border);
}
.hero-inner { text-align: center; max-width: 820px; margin: 0 auto; }
.badge {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 999px;
  background: #fef3c7;
  color: #92400e;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .2px;
  margin-bottom: 24px;
}
.hero h1 {
  font-size: 44px; line-height: 1.2;
  font-weight: 800; margin: 0 0 20px;
  color: var(--c-text);
}
.hero h1 .hl {
  background: linear-gradient(135deg, var(--c-primary) 0%, var(--c-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.lead {
  font-size: 18px; color: var(--c-text-soft); max-width: 680px; margin: 0 auto 32px;
}
.cta-row {
  display: flex; gap: 12px; justify-content: center; flex-wrap: wrap;
  margin-bottom: 16px;
}
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 13px 24px;
  font-size: 15px; font-weight: 600;
  border-radius: var(--radius);
  text-decoration: none;
  border: 1.5px solid transparent;
  transition: all .15s;
  cursor: pointer;
}
.btn-primary {
  background: var(--c-primary); color: white;
  box-shadow: var(--shadow-md);
}
.btn-primary:hover:not(.disabled) { background: var(--c-primary-dark); }
.btn-primary.disabled {
  background: #cbd5e1; color: #64748b; cursor: not-allowed; box-shadow: none;
}
.btn-ghost {
  background: transparent; color: var(--c-primary); border-color: var(--c-primary);
}
.btn-ghost:hover { background: var(--c-primary); color: white; }
.hero-note {
  font-size: 14px; color: var(--c-text-mute); margin-top: 24px;
}

@media (max-width: 640px) {
  .hero { padding: 56px 0 48px; }
  .hero h1 { font-size: 32px; }
  .lead { font-size: 16px; }
}

/* ─────── FEATURES ─────── */
.features { padding: 72px 0; background: var(--c-surface); }
.features h2,
.process h2,
.lookup h2 {
  text-align: center;
  font-size: 30px; font-weight: 700;
  margin: 0 0 40px;
  color: var(--c-text);
}
.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.card {
  padding: 32px 24px;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-lg);
  transition: transform .15s, box-shadow .15s;
}
.card:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.card-icon { font-size: 36px; margin-bottom: 16px; }
.card h3 { margin: 0 0 10px; font-size: 18px; font-weight: 700; }
.card p { margin: 0; color: var(--c-text-soft); font-size: 15px; }

@media (max-width: 820px) {
  .cards { grid-template-columns: 1fr; gap: 16px; }
}

/* ─────── PROCESS ─────── */
.process { padding: 72px 0; background: var(--c-bg); }
.steps {
  max-width: 720px; margin: 0 auto;
  padding-left: 0; list-style: none;
  counter-reset: step;
}
.steps li {
  position: relative;
  padding: 18px 20px 18px 64px;
  margin-bottom: 14px;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius);
  font-size: 16px;
  counter-increment: step;
}
.steps li::before {
  content: counter(step);
  position: absolute; left: 18px; top: 18px;
  width: 32px; height: 32px;
  background: var(--c-primary); color: white;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 14px;
}

/* ─────── LOOKUP ─────── */
.lookup { padding: 72px 0; background: var(--c-surface); border-top: 1px solid var(--c-border); }
.lookup-box { text-align: center; max-width: 600px; }
.lookup p { color: var(--c-text-soft); margin-bottom: 24px; }
.lookup code {
  background: #f1f5f9; padding: 2px 8px; border-radius: 4px;
  font-size: 14px; color: var(--c-primary);
}
.lookup-form {
  display: flex; gap: 8px; max-width: 480px; margin: 0 auto;
}
.lookup-form input {
  flex: 1; padding: 12px 16px;
  border: 1px solid var(--c-border); border-radius: var(--radius);
  font-size: 15px; outline: none;
}
.lookup-form input:disabled { background: #f1f5f9; color: var(--c-text-mute); }
.lookup-form button {
  padding: 12px 24px;
  background: var(--c-primary); color: white;
  border: none; border-radius: var(--radius);
  font-size: 15px; font-weight: 600; cursor: pointer;
}
.lookup-form button:disabled { background: #cbd5e1; cursor: not-allowed; }

/* ─────── FOOTER ─────── */
.footer {
  background: #0f172a; color: #cbd5e1;
  padding: 48px 0 32px;
}
.footer-inner {
  display: flex; justify-content: space-between; gap: 32px; flex-wrap: wrap;
}
.footer-brand { font-size: 18px; font-weight: 700; color: white; }
.footer-sub { font-size: 14px; color: #94a3b8; margin-top: 4px; }
.footer-meta { font-size: 14px; line-height: 2; text-align: right; }
.footer-meta a { color: var(--c-accent); text-decoration: none; }
.footer-meta a:hover { text-decoration: underline; }
.footer-note { margin-top: 16px; font-size: 13px; color: #64748b; }

@media (max-width: 720px) {
  .footer-inner { flex-direction: column; }
  .footer-meta { text-align: left; }
}