/* ============================================================
   THUẬN PHONG 2026 — A11Y + MOBILE + SAFE MODERN ENHANCEMENTS
   Loaded AFTER style.css. Only additive — no desktop overrides.
   ============================================================ */

/* =====================================================
   TOKENS — spring easings + depth scale (new utilities)
   ===================================================== */
:root {
  color-scheme: light;
  --ease-spring:   cubic-bezier(.34, 1.56, .64, 1);
  --ease-ios:      cubic-bezier(.25, 1, .30, 1);
  --ease-emphasis: cubic-bezier(.2, 0, 0, 1);

  --depth-1: 0 1px 2px rgba(17,24,39,.06), 0 1px 3px rgba(17,24,39,.04);
  --depth-2: 0 4px 6px -1px rgba(17,24,39,.07), 0 2px 4px -2px rgba(17,24,39,.04);
  --depth-3: 0 10px 15px -3px rgba(17,24,39,.08), 0 4px 6px -4px rgba(17,24,39,.04);
  --depth-4: 0 20px 25px -5px rgba(17,24,39,.10), 0 8px 10px -6px rgba(17,24,39,.04);
}

/* =====================================================
   ACCESSIBILITY BASELINE
   ===================================================== */

/* Skip link */
.skip-link {
  position: fixed; top: -100px; left: 12px; z-index: 10000;
  padding: 12px 20px; background: var(--ink); color: var(--white);
  font-size: 14px; font-weight: 600; border-radius: 8px;
  text-decoration: none;
  transition: top .2s var(--ease-emphasis);
}
.skip-link:focus-visible { top: 12px; outline: 3px solid var(--amber-2); outline-offset: 2px; }

/* Focus ring — keyboard only */
a:focus-visible, button:focus-visible, .btn:focus-visible,
input:focus-visible, select:focus-visible, textarea:focus-visible,
[tabindex]:focus-visible, .faq-q:focus-visible, .rfq-step-tab:focus-visible {
  outline: 2px solid var(--amber-2);
  outline-offset: 3px;
}
input:focus-visible, select:focus-visible, textarea:focus-visible {
  border-color: var(--amber-2);
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }
  .fade-up, .slide-in-left, .slide-in-right, .scale-in {
    opacity: 1 !important; transform: none !important;
  }
}

/* Touch target min 44px on coarse pointers */
@media (hover: none) and (pointer: coarse) {
  a.btn, button, .menu-toggle, .faq-q, .float-btn {
    min-height: 44px;
  }
}

/* Tabular figures for counters */
.num-v, [data-counter], [data-since], .hero-stat-v {
  font-variant-numeric: tabular-nums;
}

/* =====================================================
   MOBILE BREAKPOINTS — 768 / 640 / 480
   ONLY activates below breakpoint — desktop untouched
   ===================================================== */

/* ---------- @768 (tablet) ---------- */
@media (max-width: 768px) {
  :root { --header-h: 72px; }
  .container, .container-narrow { padding: 0 24px; }
  section { padding: 72px 0; }
  section.tight { padding: 40px 0; }

  h1 { font-size: clamp(30px, 7vw, 44px); }
  h2 { font-size: clamp(24px, 5vw, 34px); }
  h3 { font-size: clamp(19px, 4vw, 24px); }

  /* Stack 2-column grids — covers both spaced and unspaced inline styles */
  [style*="grid-template-columns:1fr 1fr"],
  [style*="grid-template-columns: 1fr 1fr"],
  [style*="grid-template-columns:1fr 1.4fr"],
  [style*="grid-template-columns: 1fr 1.4fr"],
  [style*="grid-template-columns:1.4fr 1fr"],
  [style*="grid-template-columns: 1.4fr 1fr"],
  [style*="grid-template-columns:1fr 1.6fr"],
  [style*="grid-template-columns: 1fr 1.6fr"],
  [style*="grid-template-columns:1.6fr 1fr"],
  [style*="grid-template-columns: 1.6fr 1fr"],
  [style*="grid-template-columns:1.1fr 1fr"],
  [style*="grid-template-columns: 1.1fr 1fr"],
  [style*="grid-template-columns:1fr 1.1fr"],
  [style*="grid-template-columns: 1fr 1.1fr"],
  [style*="grid-template-columns:1fr 1.2fr"],
  [style*="grid-template-columns: 1fr 1.2fr"],
  [style*="grid-template-columns:1.2fr 1fr"],
  [style*="grid-template-columns: 1.2fr 1fr"],
  [style*="grid-template-columns:1fr 1.3fr"],
  [style*="grid-template-columns: 1fr 1.3fr"],
  [style*="grid-template-columns:1.3fr 1fr"],
  [style*="grid-template-columns: 1.3fr 1fr"] {
    grid-template-columns: 1fr !important;
    gap: 40px !important;
  }

  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .product-grid { grid-template-columns: repeat(2, 1fr); gap: 16px; }

  /* Nav collapse */
  .nav-menu {
    position: fixed; inset: var(--header-h) 0 auto 0;
    background: var(--white);
    flex-direction: column;
    padding: 20px;
    border-bottom: 1px solid var(--line);
    box-shadow: var(--depth-3);
    transform: translateY(-120%);
    transition: transform .35s var(--ease-ios);
    gap: 4px;
    z-index: 49;
  }
  .nav-menu.open { transform: translateY(0); }
  .nav-menu li a { display: block; padding: 14px 16px; border-radius: 10px; font-size: 16px; }
  .nav-menu li a.active { background: var(--amber-light); color: var(--amber); }
  .nav-phone { display: none; }
  .menu-toggle { display: inline-flex; align-items: center; justify-content: center; width: 44px; height: 44px; }

  /* Hero right-side image fades further on mobile */
  .hero-page[style*="--hero-img"]::after {
    width: 100%; opacity: .18;
    -webkit-mask-image: linear-gradient(180deg, transparent 0%, #000 60%);
    mask-image: linear-gradient(180deg, transparent 0%, #000 60%);
  }
}

/* ---------- @640 (small tablet / large phone) ---------- */
@media (max-width: 640px) {
  .container, .container-narrow { padding: 0 20px; max-width: 100%; }
  section { padding: 56px 0; }

  h1 { font-size: clamp(26px, 8vw, 36px); line-height: 1.1; }
  h2 { font-size: clamp(22px, 6vw, 30px); }

  .grid-3, .grid-4 { grid-template-columns: 1fr; gap: 16px; }
  .product-grid { grid-template-columns: 1fr; }

  /* Scrollable spec tables */
  .spec-table {
    display: block;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    max-width: 100%;
  }

  .float-btns { bottom: 16px; right: 16px; }
  .float-btn { width: 52px; height: 52px; }
}

/* ---------- @480 (small phone) ---------- */
@media (max-width: 480px) {
  .container, .container-narrow { padding: 0 16px; }
  section { padding: 48px 0; }

  h1 { font-size: clamp(24px, 9vw, 32px); }
  .hero-page-sub { font-size: 15px; }
  .breadcrumb { padding: 8px 14px; font-size: 10px; letter-spacing: .1em; }

  .btn { padding: 10px 18px; font-size: 14px; }
  .btn-lg { padding: 14px 22px; font-size: 15px; }

  .nav-cta .btn-sm { display: none; }

  /* Stack action groups full-width */
  .hero-actions, .cta-side {
    flex-direction: column !important;
    align-items: stretch !important;
  }
  .hero-actions .btn, .cta-side .btn { width: 100% !important; }

  .hero-page { padding: 96px 0 48px !important; min-height: auto !important; }
}

/* =====================================================
   MICRO-INTERACTIONS — additive only
   ===================================================== */

/* Press feedback — scale down slightly on click (complements existing hover lift) */
.btn:active { transform: scale(.97); transition: transform .1s var(--ease-emphasis); }

/* Link arrow — subtle shift on hover */
.link-arrow:hover svg, .btn-arrow:hover svg {
  transform: translateX(4px);
  transition: transform .3s var(--ease-spring);
}

/* =====================================================
   COMING-SOON POST CARDS (tin-tuc honesty fix)
   ===================================================== */
.post-card.post-coming {
  cursor: default;
  opacity: .78;
  filter: grayscale(.3);
  transition: none;
}
.post-card.post-coming:hover {
  transform: none;
  box-shadow: var(--depth-1);
}
.post-card.post-coming .post-img {
  position: relative;
}
.post-card.post-coming .post-img::after {
  content: '';
  position: absolute; inset: 0;
  background: linear-gradient(135deg, rgba(17,24,39,.1), rgba(17,24,39,.22));
  pointer-events: none;
}
.post-badge {
  display: inline-block;
  padding: 3px 10px;
  background: linear-gradient(135deg, var(--amber-2), var(--amber));
  color: var(--white);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
  border-radius: 99px;
  box-shadow: 0 2px 8px rgba(249,115,22,.3);
}

/* =====================================================
   VIEW TRANSITIONS (progressive enhancement)
   ===================================================== */
@view-transition { navigation: auto; }
::view-transition-old(root), ::view-transition-new(root) {
  animation-duration: .35s;
  animation-timing-function: var(--ease-ios);
}

/* =====================================================
   TYPOGRAPHY POLISH
   ===================================================== */
h1, h2, h3 { text-wrap: balance; }
p, li { text-wrap: pretty; }

/* =====================================================
   FORM UX — inline validation visual feedback
   ===================================================== */
.rfq-wrap input:user-invalid,
.rfq-wrap select:user-invalid,
.rfq-wrap textarea:user-invalid {
  border-color: var(--crimson);
}
.rfq-wrap button[disabled] {
  opacity: .6; cursor: wait;
}

/* =====================================================
   PRINT STYLES
   ===================================================== */
@media print {
  .site-header, .float-btns, .scroll-progress, .cta-band, .site-footer,
  .skip-link, .menu-toggle, .nav-cta { display: none !important; }
  body { background: white; color: black; }
  a { color: black; text-decoration: underline; }
  section { padding: 20px 0; page-break-inside: avoid; }
  h1, h2, h3 { page-break-after: avoid; }
  .hero-page { padding: 20px 0 !important; min-height: auto !important; }
  .hero-page::before, .hero-page::after { display: none !important; }
}