/* Bảng màu "Cyber Ops" dùng chung (../../DESIGN_TOKENS.md); chế độ sáng
   theo bảng "dễ đọc ngoài trời" của driver/web. */
:root {
  --bg: #0B0F15;
  --card: #11151A;
  --surface: #181c22;
  --text: #dfe2eb;
  --text-soft: #c2c6d8;
  --muted: #8c90a1;
  --border: rgba(255, 255, 255, .08);
  --primary: #0066ff;
  --primary-dark: #0052cc;
  --glow: #00F0FF;
  --success: #4bc490;
  --warning: #e0a83f;
  --warning-soft: #3a2c11;
  --danger: #FF3B30;
  --info-soft: #0c1e3d;
  --info-soft-text: #8fb4ff;
  --shadow: 0 12px 30px rgba(0, 0, 0, .45);
  --font-ui: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, monospace;
  color-scheme: dark;
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) {
    --bg: #F4F6FA;
    --card: #FFFFFF;
    --surface: #EDF0F5;
    --text: #10131A;
    --text-soft: #2B3140;
    --muted: #545B6E;
    --border: rgba(16, 19, 26, .12);
    --primary: #0052CC;
    --primary-dark: #003f9e;
    --glow: #0052CC;
    --success: #167A4B;
    --warning: #8A5300;
    --warning-soft: #FFF3DC;
    --danger: #C81E13;
    --info-soft: #E6EEFF;
    --info-soft-text: #0052CC;
    --shadow: 0 8px 24px rgba(16, 19, 26, .08);
    color-scheme: light;
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.55 var(--font-ui);
  -webkit-text-size-adjust: 100%;
}
a { color: var(--primary); }
.mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }
.wrap { width: 100%; max-width: 1080px; margin: 0 auto; padding: 0 16px; }
[hidden] { display: none !important; }

/* Top bar */
.topbar {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.topbar-row { display: flex; align-items: center; justify-content: space-between; height: 56px; gap: 12px; }
.brand { font-weight: 700; font-size: 18px; color: var(--text); text-decoration: none; letter-spacing: -.01em; }
.topnav { display: flex; align-items: center; gap: 16px; }
.topnav a:not(.btn) { color: var(--text-soft); text-decoration: none; font-size: 14px; }
@media (max-width: 560px) { .topnav a:not(.btn) { display: none; } }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 44px; padding: 0 18px; border-radius: 10px;
  font: 600 15px/1 var(--font-ui); text-decoration: none; cursor: pointer;
  border: 1px solid transparent;
}
.btn--primary { background: var(--primary); color: #fff; }
.btn--primary:hover { background: var(--primary-dark); }
.btn--ghost { background: transparent; color: var(--text); border-color: var(--border); }
.btn--ghost:hover { border-color: var(--muted); }
.btn--sm { min-height: 36px; padding: 0 14px; font-size: 14px; }
.btn--block { width: 100%; }
.btn:focus-visible, .copy:focus-visible, .link:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible {
  outline: 2px solid var(--glow); outline-offset: 2px;
}

/* Hero */
.hero { padding: 56px 16px 24px; }
.eyebrow { color: var(--glow); font-weight: 600; font-size: 14px; margin: 0 0 12px; }
.hero h1 { font-size: clamp(30px, 6vw, 48px); line-height: 1.1; letter-spacing: -.02em; margin: 0 0 16px; max-width: 18ch; }
.hero h1 em { font-style: normal; color: var(--primary); }
.lead { color: var(--text-soft); font-size: 18px; max-width: 60ch; margin: 0 0 24px; }
.proof { list-style: none; padding: 0; margin: 0 0 28px; display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 12px; }
.proof li { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 14px 16px; }
.proof strong { display: block; font-size: 24px; color: var(--text); }
.proof span { color: var(--muted); font-size: 14px; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; }

/* Sections */
.section { padding: 40px 16px; }
.section h2 { font-size: 26px; letter-spacing: -.01em; margin: 0 0 8px; }
.section-lead { color: var(--text-soft); margin: 0 0 20px; }

/* Plans */
.plans { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; }
.plan {
  background: var(--card); border: 1px solid var(--border); border-radius: 16px;
  padding: 22px; display: flex; flex-direction: column; gap: 14px; box-shadow: var(--shadow);
}
.plan--hl { border: 2px solid var(--primary); }
.plan-head { display: flex; align-items: baseline; justify-content: space-between; gap: 8px; }
.plan-name { font-size: 20px; font-weight: 700; margin: 0; }
.badge { font-size: 12px; font-weight: 600; color: var(--info-soft-text); background: var(--info-soft); padding: 3px 8px; border-radius: 999px; }
.plan-tag { color: var(--text-soft); margin: 0; }
.price { margin: 0; }
.price strong { font-size: 30px; }
.price span { color: var(--muted); }
.setup { color: var(--muted); font-size: 14px; margin: -8px 0 0; }
.feats { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; flex: 1; }
.feats li { padding-left: 24px; position: relative; color: var(--text-soft); font-size: 15px; }
.feats li::before { content: "✓"; position: absolute; left: 0; color: var(--success); font-weight: 700; }
.feats li.no { color: var(--muted); }
.feats li.no::before { content: "–"; color: var(--muted); }

/* Steps */
.steps { list-style: none; padding: 0; margin: 0; counter-reset: s; display: grid; grid-template-columns: repeat(auto-fit, minmax(190px, 1fr)); gap: 12px; }
.steps li { counter-increment: s; background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 16px; }
.steps li::before { content: counter(s); display: inline-grid; place-items: center; width: 28px; height: 28px; border-radius: 50%; background: var(--primary); color: #fff; font-weight: 700; font-size: 14px; margin-bottom: 8px; }
.steps strong { display: block; }
.steps span { color: var(--muted); font-size: 14px; }

/* Register */
.register { display: grid; grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr); gap: 16px; align-items: start; }
@media (max-width: 820px) { .register { grid-template-columns: 1fr; } }
.card { background: var(--card); border: 1px solid var(--border); border-radius: 16px; padding: 20px; }
.form { display: grid; gap: 16px; }
.field { display: grid; gap: 6px; }
.label { font-weight: 600; font-size: 14px; }
input:not([type="radio"]):not([type="checkbox"]), select, textarea {
  width: 100%; min-height: 44px; padding: 10px 12px; border-radius: 10px;
  background: var(--surface); color: var(--text); border: 1px solid var(--border);
  font: 16px var(--font-ui);
}
textarea { resize: vertical; }
input[aria-invalid="true"] { border-color: var(--danger); }
.hint { color: var(--muted); font-size: 13px; margin: 0; }
.error { color: var(--danger); margin: 0; font-size: 14px; }
.seg { display: flex; flex-wrap: wrap; gap: 8px; }
.seg label {
  display: inline-flex; align-items: center; gap: 6px; min-height: 40px; padding: 0 14px;
  border: 1px solid var(--border); border-radius: 10px; cursor: pointer; font-size: 15px; background: var(--surface);
}
.seg label:has(input:checked) { border-color: var(--primary); background: var(--info-soft); color: var(--text); }
.seg input { accent-color: var(--primary); margin: 0; width: 18px; height: 18px; flex: none; }
.seg label { white-space: nowrap; }
.seg small { color: var(--success); font-weight: 600; }

.summary { position: sticky; top: 72px; }
.summary h3 { margin: 0 0 12px; font-size: 18px; }
.kv { display: grid; grid-template-columns: auto 1fr; gap: 8px 16px; margin: 0; }
.kv dt { color: var(--muted); }
.kv dd { margin: 0; text-align: right; overflow-wrap: anywhere; }
.kv .total { font-weight: 700; font-size: 18px; color: var(--text); padding-top: 8px; border-top: 1px solid var(--border); }

/* Payment */
.pay { margin-top: 16px; display: grid; gap: 20px; }
.pay-head { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; }
.pay-head h3 { margin: 0; font-size: 20px; }
.link { background: none; border: 0; color: var(--primary); cursor: pointer; font: 600 14px var(--font-ui); padding: 4px; }
.pay-grid { display: grid; grid-template-columns: 260px minmax(0, 1fr); gap: 24px; align-items: start; }
@media (max-width: 680px) { .pay-grid { grid-template-columns: 1fr; } }
.qr { margin: 0; text-align: center; }
.qr img { width: 100%; max-width: 260px; aspect-ratio: 1; object-fit: contain; background: #fff; border-radius: 12px; padding: 8px; }
.qr figcaption { color: var(--muted); font-size: 13px; margin-top: 8px; }
.kv--copy dd { display: flex; justify-content: flex-end; align-items: center; gap: 8px; flex-wrap: wrap; }
.memo { color: var(--glow); font-weight: 600; }
.copy {
  min-height: 32px; padding: 0 10px; border-radius: 8px; border: 1px solid var(--border);
  background: var(--surface); color: var(--text-soft); font: 600 12px var(--font-ui); cursor: pointer;
}
.copy.done { color: var(--success); border-color: var(--success); }
.warn { margin: 0; padding: 12px 14px; border-radius: 10px; background: var(--warning-soft); color: var(--warning); }
.notify { border-top: 1px solid var(--border); padding-top: 18px; display: grid; gap: 12px; }
.notify h4 { margin: 0; font-size: 17px; }
.notify p { margin: 0; color: var(--text-soft); }
.message {
  margin: 0; padding: 12px 14px; border-radius: 10px; background: var(--surface); border: 1px solid var(--border);
  font: 14px/1.5 var(--font-mono); white-space: pre-wrap; overflow-wrap: anywhere; color: var(--text-soft);
}
.notify-actions { display: flex; flex-wrap: wrap; gap: 10px; }

/* FAQ */
.faq { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 14px 16px; margin-bottom: 10px; }
.faq summary { cursor: pointer; font-weight: 600; }
.faq p { color: var(--text-soft); margin: 10px 0 0; }

.ask { color: var(--text-soft); margin: 16px 0 0; }

/* Nút Zalo nổi: luôn bấm được trên điện thoại, nơi thanh đầu trang chỉ còn nút Đăng ký. */
.zalo-fab {
  position: fixed; right: 16px; bottom: 16px; z-index: 20;
  display: none; align-items: center; gap: 6px;
  min-height: 48px; padding: 0 16px; border-radius: 999px;
  background: var(--primary); color: #fff; text-decoration: none;
  font: 600 15px/1 var(--font-ui); box-shadow: var(--shadow);
}
.zalo-fab svg { width: 20px; height: 20px; }
.zalo-fab:focus-visible { outline: 2px solid var(--glow); outline-offset: 2px; }
@media (max-width: 560px) {
  .zalo-fab { display: inline-flex; }
  .zalo-fab[hidden] { display: none; }
  .footer { padding-bottom: 88px; }
  .topnav a.btn--ghost { display: none; }
}

/* Footer */
.footer { border-top: 1px solid var(--border); padding: 20px 0 32px; margin-top: 24px; }
.footer-row { display: flex; justify-content: space-between; gap: 12px; color: var(--muted); font-size: 14px; }