/* ==========================================================================
   Duc Dai Thanh Education Company — Corporate Site Styles
   ========================================================================== */

:root {
  --red: #b71c1c;
  --red-dark: #8e1515;
  --red-soft: #f8eaea;
  --green: #1b5e20;
  --green-dark: #124218;
  --green-soft: #e8f2e9;
  --gold: #c9a227;
  --gold-soft: #f7f1de;
  --ink: #1a1a1a;
  --muted: #5c5c5c;
  --line: #e6e0d6;
  --white: #ffffff;
  --paper: #faf8f5;
  --shadow: 0 10px 30px rgba(26, 26, 26, 0.08);
  --shadow-hover: 0 16px 40px rgba(183, 28, 28, 0.14);
  --radius: 16px;
  --radius-sm: 10px;
  --header-h: 72px;
  --wrap: 1120px;
  --font-display: "Literata", Georgia, serif;
  --font-body: "Be Vietnam Pro", sans-serif;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 12px);
}

body {
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--white);
  line-height: 1.65;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

ul,
ol {
  list-style: none;
}

button {
  font: inherit;
}

.wrap {
  width: min(100% - 2.5rem, var(--wrap));
  margin-inline: auto;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -100px;
  z-index: 1000;
  background: var(--red);
  color: var(--white);
  padding: 0.75rem 1rem;
  border-radius: 8px;
  font-weight: 600;
}

.skip-link:focus {
  top: 1rem;
}

/* --------------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.9rem 1.5rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  border: 2px solid transparent;
  transition:
    background 0.25s var(--ease),
    color 0.25s var(--ease),
    border-color 0.25s var(--ease),
    transform 0.25s var(--ease),
    box-shadow 0.25s var(--ease);
  cursor: pointer;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn:focus-visible {
  outline: 3px solid var(--gold);
  outline-offset: 3px;
}

.btn-primary {
  background: var(--red);
  color: var(--white);
  box-shadow: 0 8px 24px rgba(183, 28, 28, 0.28);
}

.btn-primary:hover {
  background: var(--red-dark);
  box-shadow: 0 12px 28px rgba(183, 28, 28, 0.35);
}

.btn-secondary {
  background: transparent;
  color: var(--green);
  border-color: var(--green);
}

.btn-secondary:hover {
  background: var(--green);
  color: var(--white);
}

.btn-nav {
  background: var(--green);
  color: var(--white);
  padding: 0.65rem 1.15rem;
  font-size: 0.85rem;
}

.btn-nav:hover {
  background: var(--green-dark);
}

.btn-card {
  background: var(--red-soft);
  color: var(--red);
  padding: 0.65rem 1.15rem;
  font-size: 0.85rem;
  margin-top: auto;
  align-self: flex-start;
}

.btn-card:hover {
  background: var(--red);
  color: var(--white);
}

/* --------------------------------------------------------------------------
   Header / Nav
   -------------------------------------------------------------------------- */

.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 200;
  height: var(--header-h);
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid transparent;
  transition:
    box-shadow 0.25s var(--ease),
    border-color 0.25s var(--ease);
}

.site-header.is-scrolled {
  border-bottom-color: var(--line);
  box-shadow: 0 4px 24px rgba(26, 26, 26, 0.06);
}

.nav {
  width: min(100% - 2rem, var(--wrap));
  margin-inline: auto;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
}

.nav-brand img {
  width: 44px;
  height: auto;
}

.nav-brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.nav-brand-name {
  font-weight: 800;
  font-size: 0.92rem;
  color: var(--red);
  letter-spacing: 0.01em;
}

.nav-brand-sub {
  font-size: 0.68rem;
  font-weight: 500;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.15rem;
  margin-left: auto;
}

.nav-links a {
  font-size: 0.84rem;
  font-weight: 500;
  color: var(--muted);
  padding: 0.5rem 0.75rem;
  border-radius: 999px;
  transition:
    color 0.2s,
    background 0.2s;
}

.nav-links a:hover,
.nav-links a.is-active {
  color: var(--red);
  background: var(--red-soft);
}

.nav-toggle {
  display: none;
  margin-left: auto;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--ink);
  border-radius: 2px;
  transition: 0.25s var(--ease);
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.mobile-menu {
  position: absolute;
  top: var(--header-h);
  left: 0;
  right: 0;
  background: var(--white);
  border-bottom: 1px solid var(--line);
  box-shadow: var(--shadow);
  padding: 1rem 1.25rem 1.5rem;
}

.mobile-menu[hidden] {
  display: none !important;
}

.mobile-menu ul {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.mobile-menu a {
  display: block;
  padding: 0.85rem 1rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  color: var(--ink);
}

.mobile-menu a:hover {
  background: var(--red-soft);
  color: var(--red);
}

/* --------------------------------------------------------------------------
   Hero
   -------------------------------------------------------------------------- */

.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  align-items: center;
  padding: calc(var(--header-h) + 2.5rem) 0 4rem;
  overflow: hidden;
  background:
    radial-gradient(ellipse 80% 60% at 85% 20%, rgba(201, 162, 39, 0.14), transparent 55%),
    radial-gradient(ellipse 70% 50% at 10% 80%, rgba(27, 94, 32, 0.1), transparent 50%),
    linear-gradient(165deg, #fffdf9 0%, #f4efe6 45%, #eef5ef 100%);
}

.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.hero-glow {
  position: absolute;
  width: 50%;
  height: 60%;
  right: -5%;
  top: 10%;
  background: radial-gradient(circle, rgba(183, 28, 28, 0.08), transparent 70%);
  animation: glowPulse 8s ease-in-out infinite;
}

.hero-illustration {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0.95;
}

.illu-book {
  animation: floatY 7s ease-in-out infinite;
  transform-origin: center;
}

.illu-pencil {
  animation: floatY 9s ease-in-out infinite reverse;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 720px;
}

.hero-logo {
  width: 120px;
  height: auto;
  margin-bottom: 1.25rem;
  filter: drop-shadow(0 8px 16px rgba(183, 28, 28, 0.15));
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 5.5vw, 4rem);
  font-weight: 700;
  line-height: 1.12;
  color: var(--red);
  letter-spacing: -0.02em;
  margin-bottom: 0.85rem;
}

.hero-subtitle {
  font-size: clamp(1.05rem, 2vw, 1.25rem);
  font-weight: 600;
  color: var(--green);
  margin-bottom: 1rem;
}

.hero-lead {
  font-size: 1.05rem;
  color: var(--muted);
  max-width: 34rem;
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
}

/* --------------------------------------------------------------------------
   Sections shared
   -------------------------------------------------------------------------- */

.section {
  padding: 6rem 0;
}

.section-intro {
  max-width: 640px;
  margin-bottom: 3rem;
}

.eyebrow {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 0.75rem;
}

.eyebrow-light {
  color: #e8c96a;
}

.section-intro h2,
.brand-title-row h2 {
  font-family: var(--font-display);
  font-size: clamp(1.9rem, 3.5vw, 2.75rem);
  font-weight: 700;
  line-height: 1.2;
  color: var(--ink);
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}

.section-lead {
  font-size: 1.05rem;
  color: var(--muted);
}

/* --------------------------------------------------------------------------
   Company
   -------------------------------------------------------------------------- */

.section-company {
  background:
    linear-gradient(180deg, var(--white) 0%, var(--paper) 100%);
}

.company-grid {
  display: grid;
  grid-template-columns: 1.35fr 0.85fr;
  gap: 2.5rem;
  align-items: start;
}

.company-copy p {
  color: var(--muted);
  margin-bottom: 1.15rem;
}

.company-copy strong {
  color: var(--ink);
  font-weight: 700;
}

.company-points {
  margin-top: 1.5rem;
  display: grid;
  gap: 0.75rem;
}

.company-points li {
  position: relative;
  padding-left: 1.5rem;
  font-weight: 500;
  color: var(--ink);
}

.company-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 0.55rem;
  height: 0.55rem;
  border-radius: 50%;
  background: var(--red);
}

.company-aside {
  background:
    linear-gradient(160deg, var(--white), var(--gold-soft));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 2rem 1.75rem;
  text-align: center;
  box-shadow: var(--shadow);
}

.company-aside-logo {
  width: 130px;
  margin: 0 auto 1.25rem;
}

.company-aside-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--red);
  line-height: 1.3;
  margin-bottom: 0.4rem;
}

.company-aside-legal {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--muted);
  margin-bottom: 0.75rem;
}

.company-aside-tax {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--green);
  margin-bottom: 1rem;
}

.company-aside-note {
  font-size: 0.88rem;
  color: var(--muted);
  border-top: 1px solid var(--line);
  padding-top: 1rem;
}

/* --------------------------------------------------------------------------
   Brand
   -------------------------------------------------------------------------- */

.section-brand {
  background:
    radial-gradient(ellipse at 20% 0%, rgba(201, 162, 39, 0.18), transparent 50%),
    linear-gradient(135deg, #6d1212 0%, var(--red) 40%, #8a1a1a 100%);
  color: var(--white);
}

.brand-panel {
  display: grid;
  grid-template-columns: 1.4fr 0.9fr;
  gap: 2.5rem;
  align-items: center;
}

.brand-title-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.85rem 1rem;
  margin-bottom: 0.75rem;
}

.brand-title-row h2 {
  color: var(--white);
  margin-bottom: 0;
}

.brand-badge {
  display: inline-block;
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  background: rgba(201, 162, 39, 0.2);
  border: 1px solid var(--gold);
  color: #f0d78a;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.brand-association {
  font-weight: 600;
  color: #f0d78a;
  margin-bottom: 1.25rem;
}

.brand-body {
  color: rgba(255, 255, 255, 0.88);
  margin-bottom: 1rem;
  max-width: 36rem;
}

.brand-clarifier {
  color: rgba(255, 255, 255, 0.72);
  font-size: 0.95rem;
  border-left: 3px solid var(--gold);
  padding-left: 1rem;
  max-width: 36rem;
}

.brand-panel-visual {
  display: flex;
  justify-content: center;
}

.brand-mark {
  width: min(100%, 280px);
  aspect-ratio: 1;
  border-radius: 50%;
  background:
    radial-gradient(circle at 30% 25%, rgba(201, 162, 39, 0.35), transparent 55%),
    linear-gradient(160deg, var(--green-dark), var(--green));
  border: 3px solid var(--gold);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 1.5rem;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.25);
  animation: floatY 6s ease-in-out infinite;
}

.brand-mark-vn {
  font-size: 0.85rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.75);
  margin-bottom: 0.35rem;
}

.brand-mark-name {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  color: var(--white);
  line-height: 1.1;
  margin-bottom: 0.75rem;
}

.brand-mark-by {
  font-size: 0.72rem;
  font-weight: 600;
  color: #f0d78a;
  letter-spacing: 0.04em;
  max-width: 10rem;
  line-height: 1.4;
}

/* --------------------------------------------------------------------------
   Products
   -------------------------------------------------------------------------- */

.section-products {
  background: var(--paper);
}

.products-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.25rem;
}

.product-card {
  display: flex;
  flex-direction: column;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.75rem 1.5rem;
  box-shadow: var(--shadow);
  transition:
    transform 0.3s var(--ease),
    box-shadow 0.3s var(--ease),
    border-color 0.3s var(--ease);
}

.product-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-hover);
  border-color: rgba(183, 28, 28, 0.25);
}

.product-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: var(--red-soft);
  color: var(--red);
  display: grid;
  place-items: center;
  margin-bottom: 1.15rem;
}

.product-icon svg {
  width: 28px;
  height: 28px;
}

.product-card:nth-child(2) .product-icon {
  background: var(--green-soft);
  color: var(--green);
}

.product-card:nth-child(3) .product-icon {
  background: var(--gold-soft);
  color: #9a7a1a;
}

.product-card:nth-child(4) .product-icon {
  background: linear-gradient(135deg, var(--red-soft), var(--gold-soft));
  color: var(--red-dark);
}

.product-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.65rem;
  color: var(--ink);
}

.product-card p {
  font-size: 0.92rem;
  color: var(--muted);
  margin-bottom: 1.5rem;
  flex: 1;
}

/* --------------------------------------------------------------------------
   Why Choose Us
   -------------------------------------------------------------------------- */

.section-why {
  background:
    linear-gradient(180deg, var(--white), #f3f7f3);
}

.why-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem 2rem;
}

.why-item {
  padding: 0.5rem 0 1rem;
  border-top: 2px solid var(--line);
  transition: border-color 0.25s;
}

.why-item:hover {
  border-top-color: var(--red);
}

.why-num {
  display: block;
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--gold);
  letter-spacing: 0.08em;
  margin: 1rem 0 0.5rem;
}

.why-item h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.45rem;
  color: var(--ink);
}

.why-item p {
  font-size: 0.92rem;
  color: var(--muted);
}

/* --------------------------------------------------------------------------
   Timeline
   -------------------------------------------------------------------------- */

.section-timeline {
  background: var(--paper);
}

.timeline {
  position: relative;
  max-width: 720px;
  margin-inline: auto;
  padding-left: 1.5rem;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 0.35rem;
  bottom: 0.35rem;
  width: 2px;
  background: linear-gradient(180deg, var(--gold), var(--red), var(--green));
  border-radius: 2px;
}

.timeline-item {
  position: relative;
  padding-left: 2rem;
  padding-bottom: 2.5rem;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-marker {
  position: absolute;
  left: -1.5rem;
  top: 0.35rem;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--white);
  border: 3px solid var(--red);
  box-shadow: 0 0 0 4px rgba(183, 28, 28, 0.12);
}

.timeline-item:nth-child(1) .timeline-marker {
  border-color: var(--gold);
  box-shadow: 0 0 0 4px rgba(201, 162, 39, 0.15);
}

.timeline-item:nth-child(3) .timeline-marker {
  border-color: var(--green);
  box-shadow: 0 0 0 4px rgba(27, 94, 32, 0.15);
}

.timeline-label {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 0.35rem;
}

.timeline-content h3 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: var(--ink);
}

.timeline-content p {
  color: var(--muted);
}

/* --------------------------------------------------------------------------
   Contact
   -------------------------------------------------------------------------- */

.section-contact {
  background:
    radial-gradient(ellipse at 100% 0%, rgba(27, 94, 32, 0.08), transparent 45%),
    var(--white);
}

.contact-layout {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 2rem;
  align-items: stretch;
}

.contact-info {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 2rem;
}

.contact-dl {
  display: grid;
  gap: 1.35rem;
}

.contact-dl dt {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 0.3rem;
}

.contact-dl dd {
  font-weight: 600;
  color: var(--ink);
  line-height: 1.55;
}

.dd-note {
  display: block;
  font-weight: 500;
  font-size: 0.85rem;
  color: var(--muted);
  margin-top: 0.2rem;
}

.contact-phones {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.25rem;
}

.contact-phones a {
  color: var(--red);
  font-weight: 700;
  font-size: 1.1rem;
  transition: color 0.2s;
}

.contact-phones a:hover {
  color: var(--red-dark);
  text-decoration: underline;
}

.zalo-block {
  display: flex;
  align-items: center;
  gap: 1.15rem;
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
}

.zalo-link {
  flex-shrink: 0;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.zalo-link:hover {
  transform: scale(1.03);
  box-shadow: var(--shadow);
}

.zalo-link img {
  width: 120px;
  height: 120px;
}

.zalo-title {
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.zalo-desc {
  font-size: 0.88rem;
  color: var(--muted);
}

.contact-map {
  min-height: 100%;
}

.map-placeholder {
  height: 100%;
  min-height: 360px;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background:
    linear-gradient(135deg, rgba(27, 94, 32, 0.08), rgba(183, 28, 28, 0.06)),
    repeating-linear-gradient(
      -45deg,
      transparent,
      transparent 12px,
      rgba(26, 26, 26, 0.02) 12px,
      rgba(26, 26, 26, 0.02) 24px
    ),
    var(--paper);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 2rem;
  gap: 0.75rem;
}

.map-label {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.map-address {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--ink);
  max-width: 16rem;
  margin-bottom: 0.5rem;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */

.site-footer {
  background:
    linear-gradient(180deg, #1a0a0a, #0f0f0f);
  color: rgba(255, 255, 255, 0.85);
  padding: 4rem 0 2.5rem;
}

.footer-inner {
  text-align: center;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 2rem;
}

.footer-brand img {
  width: 72px;
  margin-bottom: 1rem;
  filter: brightness(1.05);
}

.footer-company {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 700;
  color: var(--white);
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
}

.footer-tagline {
  color: #e8c96a;
  font-weight: 500;
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.5rem 1.25rem;
  margin-bottom: 2rem;
}

.footer-nav a {
  font-size: 0.88rem;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.65);
  transition: color 0.2s;
}

.footer-nav a:hover {
  color: var(--gold);
}

.footer-copy {
  font-size: 0.82rem;
  color: rgba(255, 255, 255, 0.45);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 1.5rem;
}

/* --------------------------------------------------------------------------
   Motion / Reveal
   -------------------------------------------------------------------------- */

.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition:
    opacity 0.7s var(--ease),
    transform 0.7s var(--ease);
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

.hero-content .reveal:nth-child(1) {
  transition-delay: 0.05s;
}
.hero-content .reveal:nth-child(2) {
  transition-delay: 0.15s;
}
.hero-content .reveal:nth-child(3) {
  transition-delay: 0.25s;
}
.hero-content .reveal:nth-child(4) {
  transition-delay: 0.35s;
}
.hero-content .reveal:nth-child(5) {
  transition-delay: 0.45s;
}

.products-grid .reveal:nth-child(1) {
  transition-delay: 0.05s;
}
.products-grid .reveal:nth-child(2) {
  transition-delay: 0.12s;
}
.products-grid .reveal:nth-child(3) {
  transition-delay: 0.19s;
}
.products-grid .reveal:nth-child(4) {
  transition-delay: 0.26s;
}

.why-grid .reveal:nth-child(1) {
  transition-delay: 0.05s;
}
.why-grid .reveal:nth-child(2) {
  transition-delay: 0.1s;
}
.why-grid .reveal:nth-child(3) {
  transition-delay: 0.15s;
}
.why-grid .reveal:nth-child(4) {
  transition-delay: 0.2s;
}
.why-grid .reveal:nth-child(5) {
  transition-delay: 0.25s;
}
.why-grid .reveal:nth-child(6) {
  transition-delay: 0.3s;
}

@keyframes floatY {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-12px);
  }
}

@keyframes glowPulse {
  0%,
  100% {
    opacity: 0.7;
    transform: scale(1);
  }
  50% {
    opacity: 1;
    transform: scale(1.05);
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .illu-book,
  .illu-pencil,
  .brand-mark,
  .hero-glow {
    animation: none;
  }

  .btn:hover,
  .product-card:hover {
    transform: none;
  }
}

/* --------------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------------- */

@media (max-width: 1024px) {
  .products-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .company-grid,
  .brand-panel,
  .contact-layout {
    grid-template-columns: 1fr;
  }

  .brand-panel-visual {
    order: -1;
  }

  .brand-mark {
    width: 220px;
  }
}

@media (max-width: 860px) {
  .nav-links,
  .btn-nav {
    display: none;
  }

  .nav-toggle {
    display: flex;
  }

  .why-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  :root {
    --header-h: 64px;
  }

  .wrap {
    width: min(100% - 1.5rem, var(--wrap));
  }

  .section {
    padding: 4.5rem 0;
  }

  .hero {
    padding-top: calc(var(--header-h) + 1.75rem);
    min-height: auto;
    padding-bottom: 3.5rem;
  }

  .hero-logo {
    width: 96px;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-actions .btn {
    width: 100%;
  }

  .products-grid,
  .why-grid {
    grid-template-columns: 1fr;
  }

  .contact-info {
    padding: 1.5rem;
  }

  .zalo-block {
    flex-direction: column;
    align-items: flex-start;
  }

  .map-placeholder {
    min-height: 280px;
  }

  .footer-company {
    font-size: 1.45rem;
  }
}