/* ==========================================================================
   TÂN THỨC — corporate site
   Tokens derived from "BrandGuideline (Updated).pdf"
   Palette : #0070CC Strong blue · #73B4DA Baby blue · #FEF8E0 Light grayish yellow
   Type    : Poppins (headline + body)
   ========================================================================== */

/* --- Design tokens ------------------------------------------------------ */
:root {
  /* Brand — the guideline palette, unaltered */
  --brand-blue:        #0070CC;   /* Strong blue          rgb(0 112 204)   */
  --brand-blue-soft:   #73B4DA;   /* Baby blue            rgb(115 180 218) */
  --brand-cream:       #FEF8E0;   /* Light grayish yellow rgb(254 248 224) */

  /* Surfaces.  The page ground is Baby blue; every logo, card and block of
     body copy sits on a LIGHT surface above it. Baby blue cannot carry them:
     measured against #73B4DA, logo blue #0070CC is 2.21:1, white 2.27:1 and
     cream 2.13:1 — all far below AA, and the guideline forbids placing the
     logo on low-contrast backgrounds. */
  --surface:           var(--brand-blue-soft);  /* page ground              */
  --surface-raised:    #FFFFFF;                 /* cards, header, footer    */
  --surface-alt:       var(--brand-cream);      /* alternating bands        */
  --surface-stage:     #FBF2D4;                 /* partner-logo stage       */

  /* Inks for LIGHT surfaces (white / cream). All ≥ AA on both. */
  --ink:               #12233A;
  --ink-muted:         #4A5B6E;
  --ink-faint:         #5F7080;
  --blue-ink:          #005CA8;
  --blue-quiet:        #1F6FA8;
  --line:              #E2E8EE;
  --line-strong:       #C3D0DA;
  --blue-wash:         rgba(0 112 204 / .08);

  /* Type — guideline specifies Poppins for headline AND body.
     IMPORTANT: Google Fonts' Poppins ships latin + latin-ext only; it has NO
     Vietnamese subset. Verified: U+1EE9 "ứ" falls through to the generic
     fallback. Be Vietnam Pro (geometric, near-identical proportions) is listed
     second so the browser resolves Vietnamese-only diacritics per glyph.
     For full brand fidelity, self-host the Vietnamized Poppins the guideline
     links to (fontzin.com/poppins-viet-hoa · github.com/itfoundry/Poppins):
       @font-face { font-family:"Poppins VN"; font-weight:400;
                    src:url("../fonts/Poppins-Regular.woff2") format("woff2");
                    font-display:swap; unicode-range:U+0102-1EF9; }
     …then put "Poppins VN" ahead of "Be Vietnam Pro" below. */
  --font-display: "Poppins", "Be Vietnam Pro", ui-sans-serif, system-ui, sans-serif;
  --font-body:    "Poppins", "Be Vietnam Pro", ui-sans-serif, system-ui, sans-serif;

  /* Spacing scale — 4pt rhythm */
  --space-1: .25rem;  --space-2: .5rem;   --space-3: .75rem;  --space-4: 1rem;
  --space-6: 1.5rem;  --space-8: 2rem;    --space-12: 3rem;   --space-16: 4rem;
  --space-20: 5rem;   --space-28: 7rem;

  /* Logo clear space — guideline Logo Grid: min. 2X around the mark */
  --logo-clear:    1.5rem;
  --logo-clear-lg: 2.5rem;

  --radius:      14px;
  --radius-lg:   22px;
  --shell:       76rem;
  --ring:        3px;

  --ease:        cubic-bezier(.22,.61,.36,1);
  --dur-fast:    160ms;
  --dur:         240ms;
  --dur-slow:    420ms;

  --z-header:    100;
}

/* Sections sitting directly on the Baby blue ground.
   Only dark navy clears AA on #73B4DA, so the ink tokens shift here. */
.on-blue {
  --ink-muted:   #2E3F52;   /* 4.76:1 on #73B4DA */
  --ink-faint:   #2E3F52;
  --blue-ink:    #12233A;   /* 6.98:1 */
  --blue-quiet:  #16304D;   /* 5.87:1 */
  --line:        rgb(18 35 58 / .14);
  --line-strong: rgb(18 35 58 / .34);
}
/* …but cards inside those sections are white, so they get the light inks back. */
/* The TRIKOWA card is the one box left on a light fill, so it keeps light inks. */
.on-blue .brand-card {
  --ink-muted:   #4A5B6E;
  --ink-faint:   #5F7080;
  --blue-ink:    #005CA8;
  --blue-quiet:  #1F6FA8;
  --line:        #E2E8EE;
  --line-strong: #C3D0DA;
}
/* …except the placeholder card, which has no fill — its text is still
   sitting on the Baby blue ground, so it keeps the dark inks. */
.on-blue .brand-card--empty {
  --ink-faint:   #2E3F52;
  --line-strong: rgb(18 35 58 / .34);
}

/* --- Information boxes -------------------------------------------------- */
/* Filled with Strong blue, text in cream: 4.71:1, clears AA.
   Applied to every box EXCEPT the TRIKOWA card, which stays light so the
   green partner logo keeps its contrast. */
.info-box {
  background: var(--brand-blue);
  border: 1px solid rgb(254 248 224 / .22);
  color: var(--brand-cream);
  --ink:         var(--brand-cream);
  --ink-muted:   var(--brand-cream);
  --ink-faint:   var(--brand-cream);
  --blue-ink:    var(--brand-cream);
  --blue-quiet:  var(--brand-cream);
  --line:        rgb(254 248 224 / .28);
  --line-strong: rgb(254 248 224 / .5);
}
.info-box :where(a, button):focus-visible { outline-color: var(--brand-cream); }

/* --- Reset -------------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background: var(--surface);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  touch-action: manipulation;
}

h1, h2, h3 { font-family: var(--font-display); line-height: 1.12; margin: 0; text-wrap: balance; }
p { margin: 0; text-wrap: pretty; }
ul { margin: 0; padding: 0; list-style: none; }
img, svg { display: block; max-width: 100%; }
img { height: auto; }
a { color: inherit; }

:where(a, button, [tabindex]):focus-visible {
  outline: var(--ring) solid var(--brand-blue);
  outline-offset: 3px;
  border-radius: 4px;
}
.on-blue :where(a, button):focus-visible { outline-color: var(--ink); }

.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;
}

.skip-link {
  position: absolute; left: var(--space-4); top: -100px;
  z-index: 999; padding: var(--space-3) var(--space-6);
  background: var(--brand-blue); color: #fff;
  font-weight: 600; text-decoration: none; border-radius: 0 0 var(--radius) var(--radius);
  transition: top var(--dur) var(--ease);
}
.skip-link:focus-visible { top: 0; }

.shell { width: min(100% - 2.5rem, var(--shell)); margin-inline: auto; }
@media (min-width: 768px) { .shell { width: min(100% - 4rem, var(--shell)); } }

/* --- Reveal animation --------------------------------------------------- */
.reveal { opacity: 0; transform: translateY(18px); }
.reveal.is-in {
  opacity: 1; transform: none;
  transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease);
}
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* --- Header ------------------------------------------------------------- */
.site-header {
  position: sticky; top: 0; z-index: var(--z-header);
  /* Kept near-opaque: over a saturated ground, a lightly-tinted bar drags the
     effective background down and the nav links lose contrast. */
  background: rgb(255 255 255 / .94);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color var(--dur) var(--ease), background var(--dur) var(--ease);
  padding-top: env(safe-area-inset-top);
}
.site-header.is-stuck { border-bottom-color: var(--line); background: rgb(255 255 255 / .99); }
/* Fully opaque while the mobile menu is down — the translucent bar would
   otherwise let hero content ghost through behind the logo. */
.site-header.is-nav-open { background: var(--surface-raised); backdrop-filter: none; -webkit-backdrop-filter: none; }

.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: var(--space-4);
  min-height: 4.5rem;
}

.brandmark {
  display: inline-flex; align-items: center;
  padding: var(--space-2) var(--space-2) var(--space-2) 0;
  text-decoration: none;
}
.brandmark__img {
  width: clamp(118px, 15vw, 158px); height: auto;
  transition: transform var(--dur) var(--ease);
}
.brandmark:hover .brandmark__img { transform: scale(1.03); }
@media (prefers-reduced-motion: reduce) { .brandmark:hover .brandmark__img { transform: none; } }

.header-tools { display: flex; align-items: center; gap: var(--space-2); order: 3; }

/* --- Language switch ---------------------------------------------------- */
.lang-switch {
  display: inline-flex; align-items: center;
  padding: 3px;
  background: #EDF3F8;
  border: 1px solid var(--line);
  border-radius: 999px;
}
.lang-switch__btn {
  min-width: 48px; min-height: 44px;   /* full touch target, no hit-area hacks */
  padding: 0 var(--space-3);
  border: 0; border-radius: 999px;
  background: transparent; color: var(--ink-muted);
  font-family: var(--font-display); font-size: .82rem; font-weight: 600; letter-spacing: .06em;
  cursor: pointer;
  transition: background var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease);
}
.lang-switch__btn:hover { color: var(--brand-blue); }
.lang-switch__btn.is-active { background: var(--brand-blue); color: #fff; }  /* 5.6:1 */

.nav-toggle {
  display: grid; place-items: center;
  width: 44px; height: 44px;
  background: none; border: 0; border-radius: 10px;
  color: var(--ink); cursor: pointer;
  transition: background var(--dur-fast) var(--ease);
}
.nav-toggle:hover { background: var(--blue-wash); }
.nav-toggle svg { width: 24px; height: 24px; fill: none; stroke: currentColor; stroke-width: 1.75; stroke-linecap: round; }

/* --- Primary nav -------------------------------------------------------- */
.primary-nav ul { display: flex; align-items: center; gap: var(--space-1); }
.primary-nav a {
  display: inline-flex; align-items: center;
  min-height: 44px; padding: 0 var(--space-4);
  border-radius: 999px;
  font-size: .95rem; font-weight: 500; text-decoration: none;
  color: var(--ink-muted);
  transition: color var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease);
}
.primary-nav a:hover { color: var(--brand-blue); background: var(--blue-wash); }
.primary-nav a[aria-current="true"] { color: var(--brand-blue); font-weight: 600; }

/* Keep the CTA white-on-blue in every state — the [aria-current] rule above
   would otherwise win on specificity and paint blue text on a blue pill. */
.primary-nav .nav-cta,
.primary-nav .nav-cta:hover,
.primary-nav .nav-cta[aria-current="true"] {
  margin-left: var(--space-2);
  background: var(--brand-blue); color: #fff; font-weight: 600;
}
.primary-nav .nav-cta:hover,
.primary-nav .nav-cta[aria-current="true"] { background: #005CA8; }

@media (max-width: 899px) {
  .primary-nav {
    position: absolute; inset: 100% 0 auto;
    display: grid; grid-template-rows: 0fr;
    background: var(--surface-raised);
    border-bottom: 1px solid var(--line);
    transition: grid-template-rows var(--dur) var(--ease);
  }
  .primary-nav ul {
    overflow: hidden;
    flex-direction: column; align-items: stretch;
    gap: 0; padding-inline: 1.25rem;
  }
  .primary-nav.is-open { grid-template-rows: 1fr; }
  .primary-nav.is-open ul { padding-block: var(--space-2) var(--space-6); }
  .primary-nav a { min-height: 52px; border-radius: var(--radius); }
  .primary-nav .nav-cta { margin: var(--space-2) 0 0; justify-content: center; }
  @media (prefers-reduced-motion: reduce) { .primary-nav { transition: none; } }
}
@media (min-width: 900px) {
  .nav-toggle { display: none; }
  .header-tools { order: 0; margin-left: auto; }
  .primary-nav { order: 0; }
}

/* --- Buttons ------------------------------------------------------------ */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  min-height: 48px; padding: 0 var(--space-8);
  border-radius: 999px;
  font-family: var(--font-display); font-size: 1rem; font-weight: 600;
  text-decoration: none; cursor: pointer;
  transition: transform var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease),
              color var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease);
}
.btn:active { transform: scale(.97); }
@media (prefers-reduced-motion: reduce) { .btn:active { transform: none; } }

.btn--primary { background: var(--brand-blue); color: #fff; border: 2px solid var(--brand-blue); }
.btn--primary:hover { background: #005CA8; border-color: #005CA8; }

.btn--ghost { background: transparent; color: var(--blue-ink); border: 2px solid var(--line-strong); }
.btn--ghost:hover { border-color: var(--blue-ink); background: rgb(255 255 255 / .55); }

/* --- Hero --------------------------------------------------------------- */
.hero { padding-block: clamp(3rem, 8vw, 6.5rem) clamp(3.5rem, 9vw, 7rem); }
.hero__grid { display: grid; gap: clamp(2.5rem, 6vw, 4rem); align-items: center; }
@media (min-width: 900px) { .hero__grid { grid-template-columns: 1.12fr .88fr; } }

.eyebrow {
  display: inline-flex; align-items: center; gap: var(--space-2);
  margin-bottom: var(--space-4);
  font-size: .8rem; font-weight: 600; letter-spacing: .16em; text-transform: uppercase;
  color: var(--blue-ink);
}
.eyebrow::before { content: ""; width: 28px; height: 2px; background: currentColor; border-radius: 2px; opacity: .5; }

.hero__title { font-size: clamp(2.35rem, 6.2vw, 4.15rem); font-weight: 700; letter-spacing: -.025em; }
.hero__title em { font-style: normal; color: var(--brand-blue); }
/* Accent set in cream, bold, no fill behind it — as specified.
   NOTE: cream on the Baby blue ground measures 2.13:1, under the 3:1 floor
   for large text. It is an accent word inside a headline that is otherwise
   navy at 6.98:1, so the sentence stays readable, but this word alone does
   not meet AA. See README. */
.on-blue .hero__title em {
  color: var(--brand-cream);
  font-weight: 700;
}

.hero__lede {
  max-width: 46ch; margin-top: var(--space-6);
  font-size: clamp(1.03rem, 1.4vw, 1.15rem); color: var(--ink-muted);
}
.hero__actions { display: flex; flex-wrap: wrap; gap: var(--space-3); margin-top: var(--space-8); }

/* --- The wheel ---------------------------------------------------------- */
/* "Bánh xe Nhận thức". JS spins it while the cursor is on it — it winds up
   and coasts down rather than snapping, so it reads as a wheel turning.
   NOTE: the guideline's Incorrect Usage page lists "Do not rotate the logo
   symbol". This rotation is a deliberate, signed-off exception. */
.hero__mark { display: grid; place-items: center; }
.hero__symbol {
  width: min(78%, 20rem); height: auto;
  transform-origin: 50% 50%;
}

/* --- Sections ----------------------------------------------------------- */
.section { padding-block: clamp(3.5rem, 9vw, 6.5rem); }
.section--alt {
  background: var(--surface-alt);
  --line: #E4DCC0;
  --line-strong: #CFC6A8;
}
.section--contact { padding-bottom: clamp(4rem, 10vw, 7rem); }

.section__head { margin-bottom: var(--space-8); }
.section__index {
  font-family: var(--font-display); font-size: .85rem; font-weight: 700;
  letter-spacing: .18em; color: var(--blue-quiet);
}
.section__title { margin-top: var(--space-2); font-size: clamp(1.85rem, 4vw, 2.85rem); font-weight: 600; letter-spacing: -.02em; }
.section__lede {
  max-width: 62ch; margin-bottom: var(--space-12);
  font-size: clamp(1.03rem, 1.3vw, 1.13rem); color: var(--ink-muted);
}
.section__lede strong { color: var(--ink); font-weight: 600; }

/* --- Pillars ------------------------------------------------------------ */
.pillars { display: grid; gap: var(--space-6); }
@media (min-width: 640px)  { .pillars { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1000px) { .pillars { grid-template-columns: repeat(4, 1fr); } }

.pillar {
  padding: var(--space-8) var(--space-6);
  border-radius: var(--radius-lg);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.pillar:hover { transform: translateY(-4px); border-color: var(--brand-cream); }
@media (prefers-reduced-motion: reduce) { .pillar:hover { transform: none; } }

.pillar__icon {
  display: grid; place-items: center;
  width: 46px; height: 46px; margin-bottom: var(--space-6);
  background: rgb(254 248 224 / .16); border-radius: 13px;
  color: var(--brand-cream);
}
.pillar__icon svg { width: 23px; height: 23px; fill: none; stroke: currentColor; stroke-width: 1.75; stroke-linecap: round; stroke-linejoin: round; }
.pillar__title { font-size: 1.16rem; font-weight: 600; margin-bottom: var(--space-2); }
/* Stays at 16px on phones (readable-font-size); tightens on desktop where
   four columns share the row. */
.pillar__text { font-size: 1rem; color: var(--ink-muted); }
@media (min-width: 1000px) { .pillar__text { font-size: .96rem; } }

/* --- Vision / Mission --------------------------------------------------- */
.statements { display: grid; gap: var(--space-6); }
@media (min-width: 860px) { .statements { grid-template-columns: repeat(2, 1fr); } }

.statement {
  position: relative;
  padding: var(--space-12) var(--space-8) var(--space-8);
  border-radius: var(--radius-lg);
}
.statement__num {
  position: absolute; top: var(--space-6); right: var(--space-8);
  font-family: var(--font-display); font-size: 3.25rem; font-weight: 700;
  line-height: 1; color: var(--brand-cream); opacity: .26;
}
.statement__label {
  font-size: .82rem; font-weight: 600; letter-spacing: .16em; text-transform: uppercase;
  color: var(--blue-ink); margin-bottom: var(--space-4);
}
.statement__primary { font-size: clamp(1.13rem, 1.7vw, 1.35rem); line-height: 1.5; font-weight: 500; }
/* The other language, kept underneath for reference. */
.statement__secondary {
  margin-top: var(--space-6); padding-top: var(--space-6);
  border-top: 1px solid var(--line);
  font-size: .92rem; font-style: italic; color: var(--ink-faint);
}

/* --- Brands ------------------------------------------------------------- */
.brand-grid { display: grid; gap: var(--space-6); }
@media (min-width: 860px) { .brand-grid { grid-template-columns: 1.35fr .65fr; } }

.brand-card {
  display: flex; flex-direction: column;
  background: var(--surface-raised);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden; text-decoration: none;
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
a.brand-card:hover { transform: translateY(-5px); border-color: var(--brand-blue); }
@media (prefers-reduced-motion: reduce) { a.brand-card:hover { transform: none; } }

/* Stage = the neutral field the partner logo sits on.
   Light, high-contrast, generous clear space — per guideline logo rules. */
.brand-card__stage {
  display: grid; place-items: center;
  padding: clamp(var(--logo-clear), 6vw, var(--logo-clear-lg));
  min-height: clamp(11rem, 22vw, 15rem);
  background: var(--surface-stage);
  border-bottom: 1px solid var(--line);
}
.brand-card__logo { width: min(76%, 21rem); height: auto; transition: transform var(--dur) var(--ease); }
a.brand-card:hover .brand-card__logo,
a.brand-card:focus-visible .brand-card__logo { transform: scale(1.04); }
@media (prefers-reduced-motion: reduce) {
  a.brand-card:hover .brand-card__logo,
  a.brand-card:focus-visible .brand-card__logo { transform: none; }
}

.brand-card__body { display: block; padding: var(--space-8); }
.brand-card__name { display: block; font-family: var(--font-display); font-size: 1.3rem; font-weight: 600; letter-spacing: .01em; }
.brand-card__desc { display: block; margin-top: var(--space-2); font-size: 1rem; color: var(--ink-muted); }
.brand-card__link {
  display: inline-flex; align-items: center; gap: var(--space-2);
  margin-top: var(--space-6); font-weight: 600; color: var(--blue-ink);
}
.brand-card__link svg {
  width: 17px; height: 17px;
  fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round;
  transition: transform var(--dur) var(--ease);
}
a.brand-card:hover .brand-card__link svg { transform: translate(2px, -2px); }

.brand-card--empty {
  display: grid; place-items: center;
  min-height: 12rem;
  background: transparent;
  border-style: dashed; border-color: var(--line-strong);
}
.brand-card__soon {
  font-size: .88rem; font-weight: 500; letter-spacing: .1em; text-transform: uppercase;
  color: var(--ink-faint);
}

/* --- Contact ------------------------------------------------------------ */
.contact { display: grid; gap: clamp(2rem, 5vw, 3.5rem); align-items: center; }
@media (min-width: 860px) { .contact { grid-template-columns: 1fr 1fr; } }
.contact .section__lede { margin-bottom: 0; }

.contact__card {
  padding: var(--space-8);
  border-radius: var(--radius-lg);
}
.contact__list { margin: 0 0 var(--space-8); display: grid; gap: var(--space-4); }
.contact__list > div {
  display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-3);
  padding-bottom: var(--space-2); border-bottom: 1px solid var(--line);
}
.contact__list dt {
  min-width: 5.5rem;
  font-size: .82rem; font-weight: 600; letter-spacing: .12em; text-transform: uppercase;
  color: var(--ink-faint);
}
.contact__list dd { margin: 0; font-size: 1.05rem; font-weight: 500; }
.contact__list a {
  /* inline-flex + min-height gives these links a 44px touch target
     without changing how they sit on the baseline */
  display: inline-flex; align-items: center; min-height: 44px;
  color: var(--brand-cream);
  text-decoration: underline; text-decoration-color: rgb(254 248 224 / .55);
  text-underline-offset: 4px;
}
.contact__list a:hover { text-decoration-color: var(--brand-cream); }

.contact__card .btn { width: 100%; }
/* A Strong blue button inside a Strong blue box would vanish — invert it. */
.contact__card .btn--primary {
  background: var(--brand-cream); color: var(--brand-blue);
  border-color: var(--brand-cream);
}
.contact__card .btn--primary:hover { background: #FFFFFF; border-color: #FFFFFF; color: #005CA8; }

/* --- Footer ------------------------------------------------------------- */
.site-footer {
  padding-block: var(--space-12);
  padding-bottom: max(var(--space-12), env(safe-area-inset-bottom));
  border-top: 1px solid var(--line);
  background: var(--surface-raised);
}
.footer-inner { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: var(--space-6); }
.footer__logo { width: 138px; height: auto; }
.footer__note { font-size: .9rem; color: var(--ink-faint); }