/* ==========================================================================
   CKS landing — Chu ky so Viettel-CA cho doanh nghiep
   Mobile-first. Token theo design-system.md (Phase 3).
   Breakpoints: base <600 · sm >=600 · md >=900 · lg >=1200
   ========================================================================== */

/* ---------- 1. Tokens ---------- */
:root {
  --c-brand: #1E3A5F;
  --c-brand-tint: #EEF2F7;
  --c-brand-press: #E2E8F0;
  --c-cta: #C8102E;
  --c-cta-hover: #A30D25;
  --c-cta-active: #850A1E;
  --c-cta-tint: #FDF2F4;
  --c-text: #1F2937;
  --c-heading: #111827;
  --c-muted: #4B5563;
  --c-subtle: #6B7280;
  --c-border: #E5E7EB;
  --c-border-input: #6B7280;
  --c-bg: #FFFFFF;
  --c-bg-alt: #F5F7FA;
  --c-surface: #FFFFFF;
  --c-surface-dark: #1F2937;
  --c-surface-brand: #1E3A5F;
  --c-surface-info: #F1F5F9;
  --c-info-text: #334155;
  --c-success: #15803D;
  --c-success-bg: #F0FDF4;
  --c-warning: #B45309;
  --c-warning-bg: #FFFBEB;
  --c-error: #B91C1C;
  --c-error-bg: #FEF2F2;
  --c-focus: #1D4ED8;
  --c-focus-on-dark: #93C5FD;
  --c-on-dark: #F9FAFB;
  --c-on-dark-muted: #D1D5DB;
  --c-on-brand-muted: #CBD5E1;

  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;

  --s-1: 4px;
  --s-2: 8px;
  --s-3: 12px;
  --s-4: 16px;
  --s-5: 24px;
  --s-6: 32px;
  --s-7: 48px;
  --s-8: 64px;
  --s-9: 80px;

  --gutter: var(--s-4);
  --section-y: var(--s-7);
  --header-h: 56px;
  --sticky-h: 64px;

  --r-sm: 4px;
  --r-md: 8px;
  --r-lg: 12px;
  --r-full: 999px;
  --shadow-1: 0 1px 2px rgba(17, 24, 39, .06), 0 1px 3px rgba(17, 24, 39, .08);
  --shadow-2: 0 -2px 8px rgba(17, 24, 39, .10);
  --dur: 150ms;

  --fs-h1: 28px;
  --fs-h2: 22px;
  --fs-h3: 18px;
  --fs-lead: 16px;
  --fs-body: 16px;
  --fs-small: 14px;
}

@media (min-width: 600px) {
  :root {
    --gutter: var(--s-5);
    --section-y: var(--s-8);
    --fs-h1: 36px;
    --fs-h2: 26px;
    --fs-lead: 18px;
  }
}

@media (min-width: 900px) {
  :root {
    --header-h: 72px;
  }
}

@media (min-width: 1200px) {
  :root {
    --gutter: var(--s-6);
    --section-y: var(--s-9);
    --fs-h1: 44px;
    --fs-h2: 32px;
    --fs-h3: 20px;
    --fs-body: 17px;
  }
}

/* ---------- 2. Base ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + var(--s-2));
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: var(--fs-body);
  line-height: 1.6;
  color: var(--c-text);
  background: var(--c-bg);
  overflow-wrap: break-word;
}

h1, h2, h3, p, ul, ol, dl, dd { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg { display: block; max-width: 100%; }
a { color: var(--c-brand); }
button, input, select { font: inherit; color: inherit; }
[hidden] { display: none !important; }

:focus-visible {
  outline: 2px solid var(--c-focus);
  outline-offset: 2px;
}

.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;
}

.sprite { position: absolute; width: 0; height: 0; overflow: hidden; }

.icon {
  width: 20px;
  height: 20px;
  flex: none;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.skip-link {
  position: absolute;
  top: var(--s-2);
  left: var(--s-2);
  z-index: 100;
  padding: var(--s-3) var(--s-4);
  background: var(--c-brand);
  color: #fff;
  border-radius: var(--r-md);
  transform: translateY(-200%);
}
.skip-link:focus { transform: none; }

.container {
  width: 100%;
  max-width: calc(1200px + 2 * var(--gutter));
  margin: 0 auto;
  padding: 0 var(--gutter);
}
.container--narrow { max-width: calc(800px + 2 * var(--gutter)); }

/* ---------- 3. Typography ---------- */
.section { padding: var(--section-y) 0; }
.section--alt { background: var(--c-bg-alt); }

.section-title {
  font-size: var(--fs-h2);
  line-height: 1.3;
  font-weight: 700;
  color: var(--c-heading);
  text-transform: uppercase;
  margin-bottom: var(--s-4);
}
.section-title--center,
.section-lead--center { text-align: center; margin-left: auto; margin-right: auto; }

.section-lead {
  color: var(--c-muted);
  max-width: 68ch;
  margin-bottom: var(--s-5);
}

.eyebrow {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--c-brand);
  margin-bottom: var(--s-2);
}

@media (min-width: 1200px) {
  .section-title { margin-bottom: var(--s-5); }
  .eyebrow { font-size: 14px; }
}

/* ---------- 4. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--s-2);
  min-height: 48px;
  padding: 0 20px;
  border: 2px solid transparent;
  border-radius: var(--r-md);
  font-size: 16px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: .02em;
  text-transform: uppercase;
  text-decoration: none;
  text-align: center;
  cursor: pointer;
  transition: background-color var(--dur) ease-out, border-color var(--dur) ease-out, color var(--dur) ease-out;
  -webkit-tap-highlight-color: transparent;
}
.btn--lg { min-height: 52px; padding: 0 var(--s-5); }
.btn--md { min-height: 48px; }
.btn--sm { min-height: 44px; padding: 0 var(--s-4); font-size: 15px; }
.btn--block { display: flex; width: 100%; }

.btn--primary { background: var(--c-cta); color: #fff; }
.btn--primary:active { background: var(--c-cta-active); }

.btn--secondary { background: #fff; color: var(--c-brand); border-color: var(--c-brand); }
.btn--secondary:active { background: var(--c-brand-press); }

.btn--on-dark { background: transparent; color: #fff; border-color: #fff; }
.btn--on-dark:active { background: rgba(255, 255, 255, .2); }
.btn--on-dark:focus-visible { outline-color: var(--c-focus-on-dark); }

@media (hover: hover) and (pointer: fine) {
  .btn--primary:hover { background: var(--c-cta-hover); }
  .btn--primary:active { background: var(--c-cta-active); }
  .btn--secondary:hover { background: var(--c-brand-tint); }
  .btn--secondary:active { background: var(--c-brand-press); }
  .btn--on-dark:hover { background: rgba(255, 255, 255, .1); }
}

.btn[disabled],
.btn[aria-disabled="true"] {
  background: var(--c-border);
  border-color: var(--c-border);
  color: var(--c-muted);
  cursor: not-allowed;
}

/* Loading: giu mau CTA, hien spinner */
.btn .spinner { display: none; }
.btn.is-loading {
  background: var(--c-cta);
  border-color: var(--c-cta);
  color: #fff;
  cursor: progress;
}
.btn.is-loading .spinner {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255, 255, 255, .45);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.btn-group {
  display: flex;
  flex-direction: column;
  gap: var(--s-3);
}
@media (min-width: 600px) {
  .btn-group { flex-direction: row; flex-wrap: wrap; }
  .btn-group--center { justify-content: center; }
}

.link-tertiary {
  display: inline-flex;
  align-items: center;
  gap: var(--s-2);
  min-height: 44px;
  color: var(--c-brand);
  font-weight: 600;
  text-decoration: none;
}
.link-tertiary:hover,
.link-tertiary:focus-visible { text-decoration: underline; }
.link-tertiary:active { color: var(--c-heading); }

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 0;
  border-radius: var(--r-md);
  background: transparent;
  color: var(--c-brand);
  cursor: pointer;
}
.icon-btn .icon { width: 24px; height: 24px; }
.icon-btn:active { background: var(--c-brand-tint); }

/* ---------- 5. Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: #fff;
  border-bottom: 1px solid transparent;
  transition: box-shadow var(--dur) ease-out, border-color var(--dur) ease-out;
}
.site-header.is-scrolled {
  box-shadow: var(--shadow-1);
  border-bottom-color: var(--c-border);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--s-3);
  height: var(--header-h);
  transition: height var(--dur) ease-out;
}

.wordmark {
  display: flex;
  align-items: center;
  gap: var(--s-2);
  min-height: 44px;
  min-width: 0;
  color: var(--c-brand);
  text-decoration: none;
}
.wordmark__mark { width: 32px; height: 32px; flex: none; }
.wordmark__text { display: flex; flex-direction: column; min-width: 0; line-height: 1.2; }
.wordmark__name { font-weight: 700; font-size: 16px; white-space: nowrap; }
.wordmark__tag { font-size: 13px; color: var(--c-muted); white-space: nowrap; }
@media (max-width: 359px) {
  .wordmark__tag { display: none; }
}

/* Logo san pham Viettel-CA (nhan dien dich vu duoc tu van — KHONG phai logo cua don vi van hanh).
   Anh giu nguyen ty le 377:116; kich thuoc dat san => khong CLS. */
.wordmark--product { gap: 10px; }
.wordmark__logo {
  display: block;
  flex: none;
  height: 30px;
  width: auto;
  aspect-ratio: 377 / 116;
}
.wordmark__role {
  padding-left: 10px;
  border-left: 1px solid var(--c-border);
  font-size: 12px;
  line-height: 1.25;
  font-weight: 600;
  color: var(--c-muted);
  max-width: 7.5em;
}
@media (max-width: 359px) {
  .wordmark__role { display: none; }
}
@media (min-width: 900px) {
  .wordmark__logo { height: 38px; }
  .wordmark__role { font-size: 13px; max-width: none; white-space: nowrap; }
}

.site-header__actions { display: flex; align-items: center; gap: var(--s-1); flex: none; }
.header-cta,
.header-hotline { display: none; }

.nav-toggle .icon--close { display: none; }
.nav-toggle[aria-expanded="true"] .icon--open { display: none; }
.nav-toggle[aria-expanded="true"] .icon--close { display: block; }

/* Menu mobile: panel duoi header */
.site-nav {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  display: none;
  padding: var(--s-2) var(--gutter) var(--s-4);
  background: #fff;
  border-bottom: 1px solid var(--c-border);
  box-shadow: var(--shadow-1);
}
.site-nav.is-open { display: block; }
.site-nav__list a {
  display: flex;
  align-items: center;
  min-height: 48px;
  color: var(--c-text);
  font-weight: 500;
  text-decoration: none;
  border-bottom: 1px solid var(--c-border);
}
.site-nav__cta { margin-top: var(--s-4); }

@media (min-width: 900px) {
  .nav-toggle,
  .header-call { display: none !important; }
  .header-cta { display: inline-flex; }
  .header-hotline:not([hidden]) { display: inline-flex; margin-right: var(--s-3); }

  .site-nav {
    position: static;
    display: block;
    padding: 0;
    border: 0;
    box-shadow: none;
    background: transparent;
  }
  .site-nav__list { display: flex; gap: var(--s-5); }
  .site-nav__list a {
    min-height: 44px;
    border-bottom: 2px solid transparent;
    font-size: 15px;
  }
  .site-nav__list a:hover { border-bottom-color: var(--c-brand); color: var(--c-brand); }
  .site-nav__cta { display: none; }

  .site-header.is-scrolled .site-header__inner { height: 60px; }
}

/* ---------- 6. Hero ---------- */
.hero {
  padding: var(--s-5) 0 var(--s-7);
  background: linear-gradient(180deg, var(--c-bg) 0%, var(--c-bg-alt) 100%);
}
.hero__grid { display: grid; gap: var(--s-6); }

.hero__title {
  font-size: var(--fs-h1);
  line-height: 1.2;
  font-weight: 800;
  color: var(--c-heading);
  text-transform: uppercase;
  margin-bottom: var(--s-3);
}
.hero__title-line { display: block; color: var(--c-brand); }

.hero__lead {
  font-size: var(--fs-lead);
  color: var(--c-text);
  max-width: 60ch;
  margin-bottom: var(--s-4);
}

.hero__audience { display: grid; gap: var(--s-2); margin-bottom: var(--s-5); }
.hero__audience li { display: flex; align-items: center; gap: var(--s-2); font-weight: 600; }
.hero__audience .icon { color: var(--c-brand); }
.hero__audience-extra { display: none !important; }

.hero__actions { display: flex; flex-direction: column; gap: var(--s-3); margin-bottom: var(--s-4); }
.hero__pricing-link { align-self: flex-start; }

.hero__visual { max-width: 480px; width: 100%; margin: 0 auto; }
.hero__illustration { width: 100%; height: auto; }

@media (min-width: 600px) {
  .hero__audience-extra { display: flex !important; }
  .hero__actions { flex-direction: row; flex-wrap: wrap; align-items: center; }
}

@media (min-width: 900px) {
  .hero { padding: var(--s-8) 0; }
  .hero__grid { grid-template-columns: 7fr 5fr; align-items: center; gap: var(--s-7); }
}

/* ---------- 7. Disclosure ---------- */
.disclosure {
  display: flex;
  gap: var(--s-2);
  align-items: flex-start;
  font-size: var(--fs-small);
  line-height: 1.5;
  color: var(--c-muted);
}
.disclosure .icon { width: 16px; height: 16px; margin-top: 2px; color: var(--c-brand); }
.disclosure a { color: var(--c-brand); font-weight: 600; }
.disclosure--hero { max-width: 60ch; }
.disclosure--note { max-width: 68ch; margin: var(--s-5) auto 0; justify-content: center; }
.disclosure--form {
  padding: var(--s-3);
  background: var(--c-surface-info);
  color: var(--c-info-text);
  border-radius: var(--r-md);
  margin-bottom: var(--s-4);
}

/* ---------- 8. Trust bar ---------- */
.trust { background: var(--c-bg-alt); padding: var(--s-5) 0; border-top: 1px solid var(--c-border); }
.trust__list { display: grid; grid-template-columns: 1fr 1fr; gap: var(--s-4); }
.trust__item { display: flex; gap: var(--s-3); align-items: flex-start; font-size: 15px; line-height: 1.4; }
.trust__item strong { display: block; color: var(--c-heading); font-weight: 600; }
.trust__sub { display: block; font-size: var(--fs-small); color: var(--c-muted); margin-top: 2px; }

.icon-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  flex: none;
  border-radius: var(--r-full);
  background: var(--c-brand-tint);
  color: var(--c-brand);
}
.icon-badge--lg { width: 48px; height: 48px; }
.icon-badge--lg .icon { width: 24px; height: 24px; }

@media (max-width: 359px) {
  .trust__list { grid-template-columns: 1fr; }
}
@media (min-width: 900px) {
  .trust { padding: var(--s-6) 0; }
  .trust__list { grid-template-columns: repeat(4, 1fr); gap: var(--s-5); }
}

/* ---------- 8b. Promotion (uu dai rieng cua don vi van hanh) ---------- */
.promo {
  background: var(--c-surface-brand);
  color: #fff;
  padding: var(--s-7) 0;
}
.promo__inner { display: flex; flex-direction: column; align-items: flex-start; gap: var(--s-3); }
.promo__preview {
  padding: var(--s-1) var(--s-3);
  border: 1px dashed var(--c-on-brand-muted);
  border-radius: var(--r-sm);
  font-size: 13px;
  font-weight: 700;
  color: var(--c-on-brand-muted);
}
.promo__eyebrow { color: var(--c-on-brand-muted); margin-bottom: 0; }
.promo__title {
  font-size: var(--fs-h1);
  line-height: 1.2;
  font-weight: 800;
  text-transform: uppercase;
  color: #fff;
}
.promo__title-line { display: block; }
.promo__title-line::after {
  content: "";
  display: block;
  width: 56px;
  height: 4px;
  margin-top: var(--s-3);
  background: var(--c-cta);
  border-radius: 2px;
}
.promo__lead { font-size: var(--fs-lead); color: var(--c-on-brand-muted); max-width: 60ch; }
.promo__lead strong { color: #fff; }
.promo__benefit { display: flex; gap: var(--s-2); align-items: flex-start; color: #fff; font-weight: 600; max-width: 60ch; }
.promo__benefit .icon { margin-top: 3px; color: var(--c-on-brand-muted); }
.promo__actions { display: flex; flex-direction: column; gap: var(--s-3); width: 100%; margin-top: var(--s-2); }
.promo :focus-visible { outline-color: var(--c-focus-on-dark); }

.disclosure--on-dark { color: var(--c-on-brand-muted); max-width: 68ch; }
.disclosure--on-dark .icon { color: var(--c-on-brand-muted); }
.disclosure--on-dark a { color: #fff; }

.promo-terms {
  width: 100%;
  max-width: 720px;
  margin-top: var(--s-2);
  background: #fff;
  color: var(--c-text);
  border-radius: var(--r-lg);
}
.promo-terms__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--s-3);
  min-height: 48px;
  padding: var(--s-3) var(--s-4);
  font-weight: 700;
  color: var(--c-heading);
  cursor: pointer;
  list-style: none;
}
.promo-terms__summary::-webkit-details-marker { display: none; }
.promo-terms__icon { color: var(--c-brand); transition: transform var(--dur) ease-out; }
.promo-terms[open] .promo-terms__icon { transform: rotate(45deg); }
.promo-terms :focus-visible { outline-color: var(--c-focus); }
.promo-terms__list { display: grid; gap: var(--s-2); padding: 0 var(--s-4); font-size: var(--fs-small); }
.promo-terms__list div { display: grid; gap: 2px; padding-bottom: var(--s-2); border-bottom: 1px solid var(--c-border); }
.promo-terms__list dt { color: var(--c-muted); }
.promo-terms__list dd { font-weight: 600; color: var(--c-heading); }
.promo-terms__note { padding: var(--s-3) var(--s-4) var(--s-4); font-size: var(--fs-small); color: var(--c-muted); }

.pricing-promo-note {
  display: grid;
  gap: var(--s-2);
  max-width: 72ch;
  margin: var(--s-5) auto 0;
  padding: var(--s-3) var(--s-4);
  background: var(--c-cta-tint);
  border-radius: var(--r-md);
  font-size: var(--fs-small);
  color: var(--c-text);
}
.pricing-promo-note a { color: var(--c-cta); font-weight: 600; }

@media (min-width: 600px) {
  .promo__actions { flex-direction: row; flex-wrap: wrap; width: auto; }
  .promo-terms__list div { grid-template-columns: 200px 1fr; gap: var(--s-3); }
}
@media (min-width: 900px) {
  .promo { padding: var(--s-8) 0; }
  .promo__title { font-size: 40px; }
}

/* ---------- 9. Problem ---------- */
.problem { display: grid; gap: var(--s-5); }
.problem__cta { width: 100%; }
.checklist { display: grid; gap: var(--s-2); }
.checklist li {
  display: flex;
  align-items: center;
  gap: var(--s-3);
  min-height: 48px;
  padding: var(--s-3) var(--s-4);
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--r-md);
  font-weight: 500;
}
.checklist .icon { color: var(--c-cta); }

@media (min-width: 600px) {
  .checklist { grid-template-columns: 1fr 1fr; }
  .problem__cta { width: auto; }
}
@media (min-width: 900px) {
  .problem { grid-template-columns: 5fr 7fr; gap: var(--s-7); align-items: center; }
  .problem__intro { order: 0; }
}

/* ---------- 10. Use-case cards ---------- */
.card-grid { display: grid; grid-template-columns: 1fr 1fr; gap: var(--s-4); }
.card {
  display: flex;
  flex-direction: column;
  gap: var(--s-2);
  padding: var(--s-4);
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--r-lg);
}
.card .icon-badge--lg { width: 40px; height: 40px; }
.card .icon-badge--lg .icon { width: 20px; height: 20px; }
.card__title { font-size: 17px; line-height: 1.4; color: var(--c-heading); margin-top: var(--s-1); }
.card__text { font-size: 15px; line-height: 1.5; color: var(--c-muted); }

@media (max-width: 374px) {
  .card-grid { grid-template-columns: 1fr; }
}
@media (min-width: 900px) {
  .card-grid { grid-template-columns: repeat(3, 1fr); gap: var(--s-5); }
  .card { padding: var(--s-5); }
  .card .icon-badge--lg { width: 48px; height: 48px; }
  .card .icon-badge--lg .icon { width: 24px; height: 24px; }
  .card__title { font-size: var(--fs-h3); }
  .card__text { font-size: 16px; }
}

/* ---------- 11. Benefits ---------- */
.benefits { display: grid; gap: var(--s-5); }
.benefit-list { display: grid; }
.benefit {
  display: flex;
  gap: var(--s-4);
  padding: var(--s-4) 0;
  border-bottom: 1px solid var(--c-border);
}
.benefit:first-child { padding-top: 0; }
.benefit:last-child { border-bottom: 0; padding-bottom: 0; }
.benefit__icon { width: 28px; height: 28px; color: var(--c-brand); margin-top: 2px; }
.benefit__title { font-size: var(--fs-h3); line-height: 1.4; color: var(--c-heading); margin-bottom: var(--s-1); }
.benefit__text { color: var(--c-muted); }

@media (min-width: 900px) {
  .benefits { grid-template-columns: 5fr 7fr; gap: var(--s-7); }
}

/* ---------- 12. Tabs + Pricing ---------- */
.tabs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  max-width: 400px;
  margin: 0 auto var(--s-5);
  padding: var(--s-1);
  background: var(--c-bg-alt);
  border: 1px solid var(--c-border-input);
  border-radius: var(--r-md);
}
.tabs__tab {
  min-height: 48px;
  padding: 0 var(--s-4);
  border: 0;
  border-radius: var(--r-sm);
  background: transparent;
  color: var(--c-text);
  font-weight: 600;
  cursor: pointer;
  transition: background-color var(--dur) ease-out, color var(--dur) ease-out;
}
.tabs__tab[aria-selected="true"] { background: var(--c-brand); color: #fff; }
@media (hover: hover) and (pointer: fine) {
  .tabs__tab[aria-selected="false"]:hover { background: var(--c-brand-tint); }
}
.tabs__panel:focus-visible { outline-offset: 4px; }
/* Khong JS: hien ca 2 panel, co khoang cach */
.tabs__panel + .tabs__panel { margin-top: var(--s-5); }
.js .tabs__panel + .tabs__panel { margin-top: 0; }

.plan-grid { display: grid; gap: var(--s-4); }
.plan {
  position: relative;
  display: grid;
  grid-template-columns: 1fr auto;
  column-gap: var(--s-4);
  row-gap: var(--s-2);
  height: 100%;
  padding: var(--s-4);
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-1);
}
.plan.is-recommended { border: 2px solid var(--c-brand); }
.plan__badge {
  grid-column: 1 / -1;
  justify-self: start;
  padding: 2px var(--s-2);
  border-radius: var(--r-sm);
  background: var(--c-cta-tint);
  color: var(--c-cta);
  font-size: 13px;
  font-weight: 700;
  text-transform: uppercase;
}
.plan__name { font-size: 17px; line-height: 1.4; color: var(--c-heading); }
.plan__term { grid-column: 1; font-size: var(--fs-small); color: var(--c-muted); }
.plan__meta { grid-column: 1 / -1; display: grid; gap: var(--s-1); padding-top: var(--s-2); border-top: 1px solid var(--c-border); }
.plan__row { display: flex; justify-content: space-between; gap: var(--s-3); font-size: var(--fs-small); }
.plan__row dt { color: var(--c-muted); }
.plan__row dd { font-weight: 600; color: var(--c-heading); text-align: right; }
.plan__price { font-size: 18px; font-variant-numeric: tabular-nums; }
.plan__promo {
  grid-column: 1 / -1;
  padding: var(--s-2) var(--s-3);
  background: var(--c-cta-tint);
  border-radius: var(--r-md);
  font-size: var(--fs-small);
  color: var(--c-heading);
}
.plan .btn { grid-column: 1 / -1; margin-top: var(--s-2); align-self: end; }

.pricing-meta { margin-top: var(--s-4); text-align: center; font-size: var(--fs-small); color: var(--c-muted); }

@media (min-width: 900px) {
  .plan-grid { grid-template-columns: repeat(3, 1fr); gap: var(--s-5); }
  .plan { grid-template-columns: 1fr; grid-template-rows: auto auto auto 1fr auto; padding: var(--s-5); }
  .plan__name { font-size: var(--fs-h3); }
  .plan__meta { margin-top: var(--s-2); }
  .plan__price { font-size: 22px; }
}

/* ---------- 13. Process ---------- */
.steps { display: grid; gap: 0; counter-reset: none; }
.step {
  position: relative;
  display: flex;
  gap: var(--s-4);
  padding-bottom: var(--s-5);
}
.step:last-child { padding-bottom: 0; }
.step::before {
  content: "";
  position: absolute;
  left: 19px;
  top: 40px;
  bottom: 0;
  width: 2px;
  background: var(--c-border);
}
.step:last-child::before { display: none; }
.step__num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  flex: none;
  border-radius: var(--r-full);
  background: var(--c-brand);
  color: #fff;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}
.step__title { font-size: var(--fs-h3); line-height: 1.4; color: var(--c-heading); margin: var(--s-2) 0 var(--s-1); }
.step__text { color: var(--c-muted); }

@media (min-width: 900px) {
  .steps { grid-template-columns: repeat(4, 1fr); gap: var(--s-5); }
  .step { flex-direction: column; padding-bottom: 0; }
  .step::before { left: 56px; right: calc(-1 * var(--s-5)); top: 23px; bottom: auto; width: auto; height: 2px; }
  .step__num { width: 48px; height: 48px; font-size: 18px; }
  .step__title { margin-top: 0; }
}

.docs {
  margin-top: var(--s-6);
  background: #fff;
  border: 1px solid var(--c-border);
  border-radius: var(--r-lg);
}
.docs__summary {
  display: flex;
  align-items: center;
  gap: var(--s-3);
  min-height: 48px;
  padding: var(--s-3) var(--s-4);
  font-weight: 600;
  color: var(--c-heading);
  cursor: pointer;
  list-style: none;
}
.docs__summary::-webkit-details-marker { display: none; }
.docs__summary .icon { color: var(--c-brand); }
.docs__summary span { flex: 1; }
.docs__chevron { transition: transform var(--dur) ease-out; }
.docs[open] .docs__chevron { transform: rotate(45deg); }
.docs__body { padding: 0 var(--s-4) var(--s-4); }
.docs__body ul { list-style: disc; padding-left: var(--s-5); display: grid; gap: var(--s-2); }
.docs__note { margin-top: var(--s-3); font-size: var(--fs-small); color: var(--c-muted); }

.section-cta { margin-top: var(--s-5); }
.section-cta .btn { width: 100%; }
@media (min-width: 600px) {
  .section-cta .btn { width: auto; }
}

/* ---------- 14. Lead form ---------- */
.lead { background: var(--c-bg-alt); }
.lead__panel { display: grid; gap: var(--s-5); }
.lead__points { display: grid; gap: var(--s-2); }
.lead__points li { display: flex; gap: var(--s-2); align-items: flex-start; }
.lead__points .icon { color: var(--c-brand); margin-top: 3px; }
.lead__aside { margin-top: var(--s-5); padding-top: var(--s-4); border-top: 1px solid var(--c-border); }
.lead__aside-title { font-weight: 600; color: var(--c-heading); margin-bottom: var(--s-2); }
.lead__aside-actions { display: flex; flex-wrap: wrap; align-items: center; gap: var(--s-3); }

.lead__form-wrap {
  background: #fff;
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-1);
  padding: var(--s-5) var(--s-4);
}
#lead-title:focus { outline: none; }
#lead-title:focus-visible { outline: 2px solid var(--c-focus); outline-offset: 4px; }

.lead-form__required-note { font-size: var(--fs-small); color: var(--c-muted); margin-bottom: var(--s-4); }
.form-row { display: grid; gap: 0; }
.field { margin-bottom: var(--s-4); }
.field__label { display: block; font-size: 15px; font-weight: 600; line-height: 1.4; color: var(--c-heading); margin-bottom: var(--s-2); }
.req { color: var(--c-error); }
.field__input {
  display: block;
  width: 100%;
  min-height: 48px;
  padding: 10px var(--s-3);
  font-size: 16px;
  line-height: 1.4;
  background: #fff;
  border: 1px solid var(--c-border-input);
  border-radius: var(--r-md);
  transition: border-color var(--dur) ease-out, box-shadow var(--dur) ease-out;
  -webkit-appearance: none;
  appearance: none;
}
.field__input::placeholder { color: var(--c-subtle); opacity: 1; }
.field__input:focus { outline: none; border-color: var(--c-focus); box-shadow: 0 0 0 1px var(--c-focus); }
.field__input:disabled { background: var(--c-bg-alt); border-color: var(--c-border); }
.field__select {
  padding-right: 40px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%231E3A5F' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 20px;
}
.field__help { font-size: var(--fs-small); color: var(--c-muted); margin-top: var(--s-1); }
.field__error {
  display: flex;
  gap: var(--s-1);
  align-items: flex-start;
  margin-top: var(--s-2);
  font-size: var(--fs-small);
  line-height: 1.4;
  color: var(--c-error);
  font-weight: 500;
}
.field__error .icon { width: 16px; height: 16px; margin-top: 1px; }

.field.is-invalid .field__input { border: 2px solid var(--c-error); padding-left: 11px; }
.field.is-invalid .field__input:focus { box-shadow: 0 0 0 1px var(--c-error); }
.field.is-valid .field__input {
  border-color: var(--c-success);
  padding-right: 40px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%2315803D' stroke-width='2.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M20 6 9 17l-5-5'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 18px;
}

.hp { position: absolute; left: -10000px; top: auto; width: 1px; height: 1px; overflow: hidden; }

.form-alert {
  display: flex;
  gap: var(--s-3);
  align-items: flex-start;
  padding: var(--s-3) var(--s-4);
  border-radius: var(--r-md);
  margin-bottom: var(--s-4);
  font-size: 15px;
  line-height: 1.5;
}
.form-alert--error { background: var(--c-error-bg); color: var(--c-error); border: 1px solid #FCA5A5; }
.form-alert--warning { background: var(--c-warning-bg); color: var(--c-warning); border: 1px solid #FCD34D; }
.form-alert .icon { margin-top: 2px; }
.form-alert__title { font-weight: 700; }
.form-alert__extra { margin-top: var(--s-1); color: var(--c-text); }
.form-alert ul { list-style: disc; padding-left: var(--s-5); margin-top: var(--s-1); }
.form-alert a { color: inherit; font-weight: 600; }
.form-alert:focus { outline: none; }
.form-alert:focus-visible { outline: 2px solid var(--c-focus); outline-offset: 2px; }

.consent { margin-top: var(--s-3); font-size: var(--fs-small); color: var(--c-muted); }

.lead-success {
  text-align: center;
  padding: var(--s-5) var(--s-2);
  background: var(--c-success-bg);
  border-radius: var(--r-lg);
}
.lead-success__icon { width: 48px; height: 48px; margin: 0 auto var(--s-3); color: var(--c-success); fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.lead-success__title { font-size: var(--fs-h3); color: var(--c-heading); margin-bottom: var(--s-2); }
.lead-success__title:focus { outline: none; }
.lead-success__title:focus-visible { outline: 2px solid var(--c-focus); outline-offset: 4px; }
.lead-success__more { margin-top: var(--s-4); }
.lead-success__more .lead__aside-actions { justify-content: center; margin-top: var(--s-2); }

@media (min-width: 600px) {
  .form-row { grid-template-columns: 1fr 1fr; column-gap: var(--s-4); }
  .lead__form-wrap { padding: var(--s-6); }
}
@media (min-width: 900px) {
  .lead__panel { grid-template-columns: 5fr 7fr; gap: var(--s-7); align-items: start; }
}

/* ---------- 15. FAQ ---------- */
.faq { border-top: 1px solid var(--c-border); }
.faq__item { border-bottom: 1px solid var(--c-border); }
.faq__q {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--s-4);
  min-height: 56px;
  padding: var(--s-4) var(--s-2);
  font-size: 17px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--c-heading);
  cursor: pointer;
  list-style: none;
}
.faq__q::-webkit-details-marker { display: none; }
@media (hover: hover) and (pointer: fine) {
  .faq__q:hover { background: #fff; }
}
.faq__icon { color: var(--c-brand); transition: transform var(--dur) ease-out; }
.faq__item[open] .faq__icon { transform: rotate(45deg); }
.faq__a { padding: 0 var(--s-2) var(--s-4); color: var(--c-text); }
.faq__more { margin-top: var(--s-6); text-align: center; }
.faq__more p { font-weight: 600; color: var(--c-heading); margin-bottom: var(--s-3); }
.faq__more .btn-group { justify-content: center; }

/* ---------- 16. Final CTA ---------- */
.final-cta { background: var(--c-surface-brand); color: #fff; padding: var(--s-7) 0; text-align: center; }
.final-cta__inner { display: flex; flex-direction: column; align-items: center; gap: var(--s-3); }
.final-cta__title { color: #fff; margin-bottom: 0; max-width: 22ch; }
.final-cta__lead { color: var(--c-on-brand-muted); }
.final-cta__phone { font-size: 20px; font-weight: 700; }
.final-cta .btn-group { width: 100%; margin-top: var(--s-2); }
.final-cta :focus-visible { outline-color: var(--c-focus-on-dark); }
.link-on-dark {
  display: inline-flex;
  align-items: center;
  gap: var(--s-2);
  min-height: 44px;
  color: #fff;
  font-weight: 600;
}
@media (min-width: 600px) {
  .final-cta .btn-group { width: auto; }
  .final-cta__title { max-width: none; }
}
@media (min-width: 900px) {
  .final-cta { padding: var(--s-8) 0; }
}

/* ---------- 17. Footer ---------- */
.site-footer {
  background: var(--c-surface-dark);
  color: var(--c-on-dark-muted);
  font-size: var(--fs-small);
  line-height: 1.6;
  padding: var(--s-7) 0 var(--s-5);
  /* Mobile: chua cho thanh sticky de khong che dong cuoi cua footer */
  padding-bottom: calc(var(--s-5) + var(--sticky-h) + env(safe-area-inset-bottom, 0px));
}
.legal-body .site-footer { padding-bottom: var(--s-5); }
@media (min-width: 900px) {
  .site-footer { padding-bottom: var(--s-5); }
}
.site-footer a { color: var(--c-on-dark); }
.site-footer :focus-visible { outline-color: var(--c-focus-on-dark); }
.site-footer__grid { display: grid; gap: var(--s-6); }
.site-footer__title {
  font-size: 15px;
  font-weight: 700;
  color: var(--c-on-dark);
  text-transform: uppercase;
  letter-spacing: .04em;
  margin-bottom: var(--s-3);
}
.site-footer__about p + p { margin-top: var(--s-2); }
.site-footer__about strong { color: var(--c-on-dark); }
.site-footer__small { font-size: 13px; }
.site-footer__list { display: grid; gap: var(--s-1); }
.site-footer__list a { display: inline-flex; align-items: center; gap: var(--s-2); min-height: 44px; }
.site-footer__bottom {
  margin-top: var(--s-6);
  padding-top: var(--s-4);
  border-top: 1px solid rgba(255, 255, 255, .12);
  font-size: 13px;
}
@media (min-width: 900px) {
  .site-footer__grid { grid-template-columns: 6fr 3fr 3fr; gap: var(--s-7); }
}

/* ---------- 18. Sticky CTA (mobile) ---------- */
.sticky-cta {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 40;
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: 1fr;
  gap: var(--s-2);
  padding: var(--s-2) var(--s-4) calc(var(--s-2) + env(safe-area-inset-bottom, 0px));
  background: #fff;
  box-shadow: var(--shadow-2);
  transform: translateY(110%);
  visibility: hidden;
  transition: transform var(--dur) ease-out, visibility 0s linear var(--dur);
}
.sticky-cta.is-visible {
  transform: none;
  visibility: visible;
  transition: transform var(--dur) ease-out, visibility 0s;
}
.sticky-cta .btn { min-height: 48px; padding: 0 var(--s-3); }
@media (min-width: 900px) {
  .sticky-cta { display: none; }
}

/* ---------- 19. Legal pages ---------- */
.legal { padding: var(--s-6) 0 var(--s-7); }
.legal h1 { font-size: var(--fs-h2); line-height: 1.3; color: var(--c-heading); margin-bottom: var(--s-2); }
.legal h2 { font-size: var(--fs-h3); line-height: 1.4; color: var(--c-heading); margin: var(--s-6) 0 var(--s-3); }
.legal p,
.legal li { max-width: 72ch; }
.legal p + p { margin-top: var(--s-3); }
.legal ul { list-style: disc; padding-left: var(--s-5); display: grid; gap: var(--s-2); margin-top: var(--s-2); }
.legal__meta { color: var(--c-muted); font-size: var(--fs-small); }

/* ---------- 20. Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    transition-duration: 0s !important;
    transition-delay: 0s !important;
    animation-duration: 0s !important;
    animation-iteration-count: 1 !important;
  }
  .btn.is-loading .spinner { animation: none; border-color: #fff; border-top-color: rgba(255, 255, 255, .45); }
}

/* ---------- 21. Offer badge tren pricing card (uu dai rieng, chi goi du dieu kien) ---------- */
.plan__offer {
  grid-column: 1 / -1;
  display: grid;
  gap: 2px;
  padding: var(--s-2) var(--s-3);
  background: var(--c-cta-tint);
  border-radius: var(--r-md);
}
.plan__offer-badge {
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .02em;
  text-transform: uppercase;
  color: var(--c-cta);
}
.plan__offer-note { font-size: 13px; line-height: 1.4; color: var(--c-muted); }
.plan.has-offer { border-color: var(--c-cta); }

/* ---------- 22. Support ---------- */
.section-title__line { display: block; }
.support-grid { display: grid; gap: var(--s-4); }
.support-card {
  display: grid;
  gap: var(--s-2);
  padding: var(--s-5) var(--s-4);
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-top: 3px solid var(--c-brand);
  border-radius: var(--r-lg);
}
.support-card__num { font-size: 14px; font-weight: 800; color: var(--c-brand); font-variant-numeric: tabular-nums; }
.support-card__title { font-size: var(--fs-h3); line-height: 1.4; color: var(--c-heading); }
.support-card__text { color: var(--c-muted); }
@media (min-width: 900px) {
  .support-grid { grid-template-columns: repeat(3, 1fr); gap: var(--s-5); }
  .support-card { padding: var(--s-5); }
}

.benefit--highlight .benefit__title { color: var(--c-brand); }

/* Mobile: an minh hoa trang tri de Promotion dung ngay sau disclosure (thu tu uu tien mobile) */
@media (max-width: 599px) {
  .hero__visual { display: none; }
}

/* ---------- 23. Uu dai theo goi + gia sau uu dai ---------- */
.promo__period { font-size: var(--fs-small); font-weight: 700; color: #fff; }
.plan__offer--strong { background: var(--c-cta); }
.plan__offer--strong .plan__offer-badge { color: #fff; }
.plan__offer--strong .plan__offer-note { color: #fff; }
.plan__row--final dd { color: var(--c-cta); }

/* ---------- 19. Consent banner (Basic Consent) ---------- */
.cookie-consent {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 60;
  background: var(--c-surface);
  color: var(--c-text);
  border-top: 1px solid var(--c-border);
  box-shadow: var(--shadow-2);
  padding: var(--s-4) 0 calc(var(--s-4) + env(safe-area-inset-bottom, 0px));
  font-size: var(--fs-small);
  line-height: 1.5;
  max-height: 70vh;
  overflow-y: auto;
}
.cookie-consent[hidden] { display: none; }
.cookie-consent__inner { display: grid; gap: var(--s-3); }
.cookie-consent__title { font-size: 15px; font-weight: 700; color: var(--c-heading); margin-bottom: var(--s-1); }
.cookie-consent a { color: var(--c-brand); text-decoration: underline; }
.cookie-consent__status { margin-top: var(--s-2); font-weight: 600; }
.cookie-consent__actions { display: grid; grid-template-columns: 1fr 1fr; gap: var(--s-2); }
/* Khi banner hien, an thanh sticky mobile de khong chong len nhau */
.has-cookie-consent .sticky-cta { visibility: hidden; }
.cookie-consent__short { display: none; }
/* Mobile: banner gon (~130px) de disclosure o hero van nhin thay truoc khi chon */
@media (max-width: 599px) {
  .cookie-consent { padding: var(--s-2) 0 calc(var(--s-2) + env(safe-area-inset-bottom, 0px)); font-size: 13px; line-height: 1.4; }
  .cookie-consent__inner { gap: var(--s-2); }
  .cookie-consent__title { position: absolute; width: 1px; height: 1px; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; }
  .cookie-consent__long { display: none; }
  .cookie-consent__short { display: block; }
  .cookie-consent__status { margin-top: var(--s-1); }
}
@media (min-width: 900px) {
  .cookie-consent__inner { grid-template-columns: 1fr auto; align-items: center; gap: var(--s-6); }
  .cookie-consent__actions { grid-template-columns: auto auto; }
}
.consent-link {
  background: none;
  border: 0;
  padding: 0;
  font: inherit;
  color: var(--c-on-dark);
  text-decoration: underline;
  cursor: pointer;
  min-height: 44px;
}
.legal h3 { font-size: var(--fs-body); line-height: 1.4; color: var(--c-heading); margin: var(--s-5) 0 var(--s-2); }
.legal ul + p { margin-top: var(--s-3); }
.legal code { font-size: .92em; background: var(--c-bg-alt); padding: 0 var(--s-1); border-radius: var(--r-sm); }
.legal .consent-inline {
  background: none;
  border: 0;
  padding: 0;
  font: inherit;
  color: var(--c-brand);
  text-decoration: underline;
  cursor: pointer;
}