/* ===================================================
   FULLDOT — AI Training Service Page
   ai-training.css
   =================================================== */

/* ---------- 0. CSS Custom Properties ---------- */
:root {
  --accent: #d15b27;
  --accent-light: #fb923c;
  --accent-glow: rgba(209, 91, 39, .35);
  --bg-white: #fafaf9;
  --bg-dark: #0a0a0a;
  --bg-warm: #f6f1eb;
  --ink-blue: #0f1923;
  --ink-warm: #1a1510;
  --text-primary: #1a1a1a;
  --text-secondary: #555;
  --text-invert: #f5f5f5;
  --border-light: #e5e2dd;
  --border-dark: rgba(255, 255, 255, .08);
  --font-serif: 'Playfair Display', serif;
  --font-sans: 'Outfit', 'Noto Sans TC', sans-serif;
  --ease-out: cubic-bezier(.16, 1, .3, 1);
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-pill: 100px;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, .06);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, .08);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, .12);
  --nav-h: 64px;
}

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  color: var(--text-primary);
  background: var(--bg-white);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

ul,
ol {
  list-style: none;
}

button {
  font: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

/* ---------- 2. Skip Link ---------- */
.skip-link {
  position: absolute;
  top: -100%;
  left: 16px;
  z-index: 9999;
  padding: 8px 18px;
  background: var(--accent);
  color: #fff;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: .875rem;
  transition: top .2s var(--ease-out);
}

.skip-link:focus {
  top: 12px;
}

/* ---------- 3. Focus Styles ---------- */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

:focus:not(:focus-visible) {
  outline: none;
}

/* ---------- 4. Navbar ---------- */
.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  padding: 24px 48px;
  z-index: 1000;
  background: rgba(250, 250, 249, 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: padding .3s, box-shadow .3s;
}

.navbar.scrolled {
  padding: 16px 48px;
  box-shadow: 0 1px 0 rgba(0,0,0,0.08);
}

.nav-container {
  display: flex;
  align-items: center;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
}

.logo {
  flex-shrink: 0;
}

.logo-img {
  height: 36px;
  width: auto;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
  margin-left: auto;
}

.nav-link {
  font-size: .9rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color .25s;
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width .3s var(--ease-out);
}

.nav-link:hover,
.nav-link.active,
.nav-link[aria-current="page"] {
  color: var(--accent);
}

.nav-link:hover::after,
.nav-link.active::after,
.nav-link[aria-current="page"]::after {
  width: 100%;
}

.btn-contact {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding: 8px 20px;
  background: var(--accent);
  color: #fff !important;
  font-size: .85rem;
  font-weight: 600;
  border-radius: var(--radius-pill);
  transition: background .25s, transform .25s var(--ease-out);
}

.btn-contact::after {
  display: none !important;
}

.btn-contact:hover {
  background: #b84e20;
  transform: translateY(-1px);
}

/* ---- Menu Toggle ---- */
.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  margin-left: auto;
  width: 28px;
  padding: 4px 0;
}

.menu-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: transform .3s var(--ease-out), opacity .2s;
}

.menu-toggle.active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

/* ---- Mobile Menu ---- */
.mobile-menu {
  position: fixed;
  inset: 0;
  z-index: 999;
  background: var(--bg-warm);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity .35s var(--ease-out), visibility .35s;
}

.mobile-menu.active {
  opacity: 1;
  visibility: visible;
}

.mobile-menu-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
  padding: 2rem;
  width: 100%;
  max-width: 340px;
}

.mm-brand {
  text-align: center;
  margin-bottom: .5rem;
}

.mm-brand-en {
  display: block;
  font-family: var(--font-serif);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -.02em;
}

.mm-brand-zh {
  display: block;
  font-size: .8rem;
  color: var(--text-secondary);
  margin-top: .15rem;
}

.mm-nav {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: .5rem;
}

.mm-link {
  display: flex;
  align-items: center;
  gap: .85rem;
  padding: .85rem 1rem;
  border-radius: var(--radius-md);
  transition: background .2s;
}

.mm-link:hover {
  background: rgba(0, 0, 0, .04);
}

.mm-link-active {
  background: rgba(209, 91, 39, .08);
}

.mm-icon {
  width: 22px;
  height: 22px;
  color: var(--text-secondary);
  flex-shrink: 0;
}

.mm-link-active .mm-icon {
  color: var(--accent);
}

.mm-text {
  flex: 1;
}

.mm-label {
  display: block;
  font-size: .65rem;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--text-secondary);
}

.mm-title {
  display: block;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
}

.mm-link-active .mm-title {
  color: var(--accent);
}

.mm-arrow {
  width: 16px;
  height: 16px;
  color: var(--text-secondary);
  opacity: .4;
}

.mm-cta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  width: 100%;
  padding: .85rem;
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: background .2s;
}

.mm-cta:hover {
  background: #b84e20;
}

.mm-cta-icon {
  width: 18px;
  height: 18px;
}

.mm-footer {
  display: flex;
  align-items: center;
  gap: .75rem;
  font-size: .75rem;
  color: var(--text-secondary);
}

.mm-footer a {
  color: var(--accent);
}

.mm-footer-dot {
  width: 3px;
  height: 3px;
  border-radius: 50%;
  background: var(--text-secondary);
  opacity: .4;
}

/* ---------- 5. WebGL Container ---------- */
#webgl-container,
.webgl-container {
  position: fixed;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  transition: opacity .6s var(--ease-out);
}

.webgl-dark {
  mix-blend-mode: screen;
}

.webgl-light {
  mix-blend-mode: multiply;
}

/* ---------- 6. Shared Block Styles ---------- */
.at-block {
  padding: clamp(3rem, 8vw, 6rem) clamp(1.5rem, 5vw, 4rem);
}

.at-light {
  background: var(--bg-white);
}

.at-dark {
  background: var(--ink-blue);
  color: var(--text-invert);
}

.at-warm {
  background: var(--ink-warm);
  color: var(--text-invert);
}

.at-container {
  max-width: 1100px;
  margin: 0 auto;
}

/* Section Headers */
.at-section-head {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 3rem;
}

.at-counter {
  display: inline-block;
  font-family: var(--font-serif);
  font-style: italic;
  font-size: .8rem;
  color: var(--accent);
  margin-bottom: .5rem;
}

.at-counter-light {
  color: var(--accent-light);
}

.at-block-title {
  font-size: clamp(1.5rem, 3.5vw, 2.25rem);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -.01em;
}

.at-title-light {
  color: var(--text-invert);
}

.at-en {
  display: block;
  font-family: var(--font-serif);
  font-style: italic;
  font-weight: 400;
  font-size: .75rem;
  color: var(--text-secondary);
  letter-spacing: .1em;
  margin-top: .25rem;
}

.at-title-light .at-en {
  color: rgba(255, 255, 255, .35);
}

.at-block-desc {
  font-size: .95rem;
  color: var(--text-secondary);
  margin-top: .75rem;
  line-height: 1.7;
}

.at-desc-light {
  color: rgba(255, 255, 255, .55);
}

/* ---------- 7. Hero — .at-hero ---------- */
.at-hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding: calc(var(--nav-h) + 3rem) clamp(1.5rem, 5vw, 4rem) 4rem;
}

.at-hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.at-hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  animation: kenBurns 25s ease-in-out infinite alternate;
}

@keyframes kenBurns {
  0% {
    transform: scale(1) translate(0, 0);
  }
  100% {
    transform: scale(1.08) translate(-1%, -1%);
  }
}

.at-hero-overlay {
  position: absolute;
  inset: 0;
  z-index: 1;
  background:
    linear-gradient(180deg, rgba(10, 10, 10, .62) 0%, rgba(10, 10, 10, .35) 50%, rgba(10, 10, 10, .7) 100%),
    linear-gradient(135deg, rgba(209, 91, 39, .1) 0%, rgba(251, 146, 60, .08) 50%, rgba(15, 25, 35, .12) 100%);
}

.at-hero-inner {
  position: relative;
  z-index: 3;
  text-align: center;
  max-width: 800px;
  color: #fff;
}

.at-label {
  display: inline-block;
  font-size: .72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .15em;
  color: var(--accent-light);
  margin-bottom: 1rem;
}

.at-h1 {
  font-family: var(--font-sans);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: -.02em;
  margin-bottom: .5rem;
}

.at-h1-serif {
  display: block;
  font-family: var(--font-serif);
  font-style: italic;
  font-weight: 400;
  font-size: clamp(1rem, 2.5vw, 1.5rem);
  color: rgba(255, 255, 255, .6);
  margin-top: .25rem;
}

.at-hero-desc {
  font-size: clamp(.95rem, 1.8vw, 1.15rem);
  color: rgba(255, 255, 255, .75);
  margin-top: 1rem;
  line-height: 1.7;
}

.at-hero-tags {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: .6rem;
  margin-top: 1.5rem;
}

.at-tag-pill {
  display: inline-block;
  padding: 6px 16px;
  font-size: .8rem;
  font-weight: 500;
  color: rgba(255, 255, 255, .85);
  border: 1px solid rgba(255, 255, 255, .2);
  border-radius: var(--radius-pill);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: rgba(255, 255, 255, .06);
  transition: background .25s, border-color .25s;
}

.at-tag-pill:hover {
  background: rgba(255, 255, 255, .12);
  border-color: rgba(255, 255, 255, .35);
}

.at-hero-cta {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  margin-top: 2rem;
  padding: 14px 32px;
  background: var(--accent);
  color: #fff;
  font-size: 1rem;
  font-weight: 700;
  border-radius: var(--radius-pill);
  transition: background .25s, transform .25s var(--ease-out), box-shadow .25s;
}

.at-hero-cta:hover {
  background: #b84e20;
  transform: translateY(-2px);
  box-shadow: 0 8px 30px var(--accent-glow);
}

/* ---------- 8. Flow Timeline ---------- */
.at-flow-timeline {
  position: relative;
  max-width: 720px;
  margin: 0 auto;
  padding-left: 60px;
}

.at-flow-timeline::before {
  content: '';
  position: absolute;
  left: 19px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--border-light);
}

.flow-step {
  position: relative;
  display: flex;
  align-items: flex-start;
  gap: 1.25rem;
  padding-bottom: 2.5rem;
}

.flow-step:last-child {
  padding-bottom: 0;
}

.flow-marker {
  position: absolute;
  left: -60px;
  top: 0;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 1.05rem;
  font-weight: 700;
  flex-shrink: 0;
  z-index: 1;
  box-shadow: 0 0 0 4px var(--bg-white);
}

.flow-marker-end {
  position: absolute;
  left: -60px;
  top: 0;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: #22c55e;
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  flex-shrink: 0;
  z-index: 1;
  box-shadow: 0 0 0 4px var(--bg-white);
}

.flow-body {
  flex: 1;
}

.flow-body h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: .35rem;
}

.flow-body p {
  font-size: .9rem;
  color: var(--text-secondary);
  line-height: 1.65;
}

.flow-time {
  display: inline-block;
  margin-top: .5rem;
  padding: 3px 10px;
  font-size: .72rem;
  font-weight: 600;
  color: var(--accent);
  background: rgba(209, 91, 39, .08);
  border-radius: var(--radius-pill);
}

/* ---------- 9. AI Tools Grid ---------- */
.at-tools-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  max-width: 1100px;
  margin: 0 auto;
}

.at-tool-card {
  background: rgba(255, 255, 255, .04);
  border: 1px solid rgba(255, 255, 255, .07);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  transition: background .3s, border-color .3s, transform .35s var(--ease-out);
}

.at-tool-card:hover {
  background: rgba(255, 255, 255, .08);
  border-color: rgba(255, 255, 255, .15);
  transform: translateY(-4px);
}

.at-tool-icon {
  width: 40px;
  height: 40px;
  color: var(--accent-light);
  margin-bottom: 1rem;
}

.at-tool-icon svg {
  width: 100%;
  height: 100%;
}

.at-tool-tag {
  display: inline-block;
  font-size: .65rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .1em;
  color: var(--accent-light);
  margin-bottom: .5rem;
}

.at-tool-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: .45rem;
  line-height: 1.35;
  color: var(--text-invert);
}

.at-tool-card p {
  font-size: .85rem;
  color: rgba(255, 255, 255, .55);
  line-height: 1.65;
}

/* ---------- 10. Course Cards ---------- */
.at-courses-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  max-width: 1100px;
  margin: 0 auto;
}

.at-course-card {
  background: #fff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 2rem 1.75rem;
  transition: transform .35s var(--ease-out), box-shadow .35s;
  position: relative;
}

.at-course-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.at-course-featured {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px var(--accent), var(--shadow-md);
}

.at-course-featured::before {
  content: '最受歡迎';
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  padding: 4px 16px;
  background: var(--accent);
  color: #fff;
  font-size: .7rem;
  font-weight: 700;
  border-radius: var(--radius-pill);
  letter-spacing: .05em;
}

.at-course-badge {
  display: inline-block;
  padding: 4px 14px;
  font-size: .72rem;
  font-weight: 700;
  color: var(--accent);
  background: rgba(209, 91, 39, .08);
  border-radius: var(--radius-pill);
  margin-bottom: 1rem;
}

.at-course-title {
  font-size: 1.25rem;
  font-weight: 800;
  margin-bottom: .5rem;
  line-height: 1.3;
}

.at-course-desc {
  font-size: .88rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 1.25rem;
}

.at-course-list {
  margin-bottom: 1.25rem;
}

.at-course-list li {
  position: relative;
  font-size: .85rem;
  color: var(--text-secondary);
  padding-left: 1.1rem;
  padding-bottom: .4rem;
  line-height: 1.55;
}

.at-course-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: .5em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  opacity: .6;
}

.at-course-audience {
  display: inline-block;
  font-size: .75rem;
  font-weight: 600;
  color: var(--text-secondary);
  padding: 4px 12px;
  background: rgba(0, 0, 0, .04);
  border-radius: var(--radius-pill);
}

/* ---------- 11. Benefits Grid ---------- */
.at-benefits-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
  max-width: 900px;
  margin: 0 auto;
}

.at-benefit-item {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}

.at-benefit-icon {
  width: 42px;
  height: 42px;
  flex-shrink: 0;
  color: var(--accent-light);
}

.at-benefit-icon svg {
  width: 100%;
  height: 100%;
}

.at-benefit-text h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: .3rem;
  color: var(--text-invert);
}

.at-benefit-text p {
  font-size: .85rem;
  color: rgba(255, 255, 255, .55);
  line-height: 1.65;
}

/* ---------- 12. Instructor Stats ---------- */
.at-instructor-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  max-width: 1000px;
  margin: 0 auto;
}

.at-stat-card {
  text-align: center;
  padding: 2rem 1.25rem;
  background: #fff;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  transition: transform .35s var(--ease-out), box-shadow .35s;
}

.at-stat-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.at-stat-num {
  font-size: 3rem;
  font-weight: 900;
  color: var(--accent);
  line-height: 1.1;
  letter-spacing: -.03em;
}

.at-stat-unit {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--accent);
}

.at-stat-label {
  font-size: .88rem;
  color: var(--text-secondary);
  margin-top: .4rem;
}

.at-stat-card-wide {
  grid-column: 1 / -1;
  text-align: left;
  padding: 2rem 2.5rem;
  background: linear-gradient(135deg, rgba(209, 91, 39, .04) 0%, rgba(251, 146, 60, .02) 100%);
  border-color: rgba(209, 91, 39, .15);
}

.at-stat-text h3 {
  font-size: 1.15rem;
  font-weight: 800;
  margin-bottom: .5rem;
}

.at-stat-text p {
  font-size: .9rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.at-stat-text a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color .2s;
}

.at-stat-text a:hover {
  color: #b84e20;
}

/* ---------- 13. CTA Section ---------- */
.at-cta-section {
  position: relative;
  background: var(--ink-blue);
  color: var(--text-invert);
  text-align: center;
  padding: clamp(4rem, 10vw, 7rem) clamp(1.5rem, 5vw, 4rem);
  overflow: hidden;
}

.at-cta-section::after {
  content: '';
  position: absolute;
  bottom: -40%;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 400px;
  background: radial-gradient(ellipse, var(--accent-glow) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.at-cta-inner {
  position: relative;
  z-index: 1;
  max-width: 620px;
  margin: 0 auto;
}

.at-cta-label {
  display: inline-block;
  font-size: .72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .15em;
  color: var(--accent-light);
  margin-bottom: 1rem;
}

.at-cta-title {
  font-size: clamp(1.5rem, 3.5vw, 2.25rem);
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: .75rem;
}

.at-cta-desc {
  font-size: .95rem;
  color: rgba(255, 255, 255, .6);
  margin-bottom: 2rem;
  line-height: 1.7;
}

.at-cta-actions {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.cta-btn-primary {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  padding: 14px 32px;
  background: var(--accent);
  color: #fff;
  font-size: 1rem;
  font-weight: 700;
  border-radius: var(--radius-pill);
  transition: background .25s, transform .25s var(--ease-out), box-shadow .25s;
}

.cta-btn-primary:hover {
  background: #b84e20;
  transform: translateY(-2px);
  box-shadow: 0 8px 30px var(--accent-glow);
}

.cta-btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  padding: 13px 30px;
  background: transparent;
  color: #fff;
  font-size: 1rem;
  font-weight: 600;
  border: 1.5px solid rgba(255, 255, 255, .25);
  border-radius: var(--radius-pill);
  transition: border-color .25s, background .25s;
}

.cta-btn-secondary:hover {
  border-color: rgba(255, 255, 255, .5);
  background: rgba(255, 255, 255, .06);
}

.at-cta-links {
  margin-top: 1.75rem;
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
  font-size: .8rem;
  color: rgba(255, 255, 255, .35);
}

.at-cta-links a {
  color: rgba(255, 255, 255, .4);
  transition: color .2s;
}

.at-cta-links a:hover {
  color: var(--accent-light);
}

/* ============================================
   FOOTER — Controlled by global style.css
   DO NOT add footer rules here.
   ============================================ */

@media (max-width: 1024px) {
  .nav-links {
    display: none;
  }

  .menu-toggle {
    display: flex;
  }

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

  .at-courses-grid {
    grid-template-columns: 1fr;
    max-width: 480px;
    margin: 0 auto;
  }

  .at-benefits-grid {
    grid-template-columns: 1fr;
  }

  .at-instructor-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .footer-content {
    grid-template-columns: 1fr 1fr;
  }
}

/* ---------- 16. Responsive — 640px ---------- */
@media (max-width: 640px) {
  :root {
    --nav-h: 56px;
  }

  .at-hero {
    min-height: 90vh;
    padding-top: calc(var(--nav-h) + 2rem);
  }

  .at-h1 {
    font-size: clamp(1.6rem, 7vw, 2.2rem);
  }

  .at-tag-pill {
    font-size: .72rem;
    padding: 5px 12px;
  }

  .at-flow-timeline {
    padding-left: 50px;
  }

  .flow-marker,
  .flow-marker-end {
    left: -50px;
    width: 34px;
    height: 34px;
    font-size: .9rem;
  }

  .at-flow-timeline::before {
    left: 16px;
  }

  .at-tools-grid {
    grid-template-columns: 1fr;
  }

  .at-instructor-grid {
    grid-template-columns: 1fr;
  }

  .at-stat-num {
    font-size: 2.5rem;
  }

  .at-cta-actions {
    flex-direction: column;
  }

  .footer-content {
    grid-template-columns: 1fr;
  }
}

/* ---------- 17. Reduced Motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  .at-hero-bg img {
    animation: none;
  }

  .at-tool-card:hover,
  .at-course-card:hover,
  .at-stat-card:hover {
    transform: none;
  }

  .at-hero-cta:hover,
  .cta-btn-primary:hover,
  .btn-contact:hover {
    transform: none;
  }
}

/* ---------- 18. Forced Colors (High Contrast) ---------- */
@media (forced-colors: active) {
  .at-tag-pill,
  .flow-time,
  .at-course-badge,
  .at-course-audience {
    border: 1px solid CanvasText;
  }

  .flow-marker,
  .flow-marker-end {
    border: 2px solid CanvasText;
    forced-color-adjust: none;
  }

  .at-hero-overlay {
    background: rgba(0, 0, 0, .5);
  }

  .btn-contact,
  .at-hero-cta,
  .cta-btn-primary {
    border: 1px solid ButtonText;
  }

  .at-tool-card,
  .at-course-card,
  .at-stat-card {
    border: 1px solid CanvasText;
  }

  a:focus-visible,
  button:focus-visible {
    outline: 2px solid Highlight;
  }
}