/*
 * Neuro Academy — Reference_Prototype (Session 2)
 * Surface: marketing-landing
 * Mobile-first responsive, dark-first, glass morphism.
 */

/* ============================================================
   RESET & BASE
   ============================================================ */
*,
*::before,
*::after {
  box-sizing: border-box;
}

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

html,
body {
  margin: 0;
  padding: 0;
}

body {
  background: var(--na-color-surface);
  color: var(--na-color-on-surface);
  font-family: var(--na-font-sans);
  font-size: var(--na-text-body-md);
  line-height: var(--na-leading-relaxed);
  font-weight: var(--na-weight-regular);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
}

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

a {
  color: var(--na-color-primary-300);
  text-decoration: none;
  transition: color var(--na-motion-fast) var(--na-ease-out);
}

a:hover {
  color: var(--na-color-primary-500);
}

a:focus-visible,
button:focus-visible,
[role="button"]:focus-visible,
.na-interactive:focus-visible {
  outline: 2px solid var(--na-color-focus);
  outline-offset: 2px;
  border-radius: var(--na-radius-sm);
}

button {
  font-family: inherit;
  font-size: inherit;
  cursor: pointer;
  border: 0;
  background: transparent;
  color: inherit;
}

h1, h2, h3, h4 {
  margin: 0;
  font-weight: var(--na-weight-semibold);
  letter-spacing: var(--na-tracking-snug);
  line-height: var(--na-leading-snug);
}

p {
  margin: 0;
}

ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

::selection {
  background: var(--na-color-primary-500);
  color: var(--na-color-neutral-0);
}

/* ============================================================
   AURORA BACKGROUND — dynamic, travelling orbs (purple/indigo/blue)
   ============================================================ */
.na-bg-aurora {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  overflow: hidden;
}

/* Each orb travels across the viewport in its own orbital loop.
   Palette is constrained to purple / indigo / blue family. */
.na-bg-aurora__orb {
  position: absolute;
  top: 0;
  left: 0;
  border-radius: 50%;
  filter: blur(90px);
  mix-blend-mode: screen;
  will-change: transform, opacity;
}

.na-bg-aurora__orb--1 {
  /* Deep blue */
  width: 56vw;
  height: 56vw;
  background: radial-gradient(circle at 35% 35%,
    #3D5BD9 0%,
    transparent 62%);
  opacity: 0.65;
  animation: aurora-travel-1 22s cubic-bezier(0.45, 0, 0.55, 1) infinite,
             aurora-pulse-a 9s ease-in-out infinite;
}

.na-bg-aurora__orb--2 {
  /* Violet / purple */
  width: 64vw;
  height: 64vw;
  background: radial-gradient(circle at 50% 50%,
    #7A3FE4 0%,
    transparent 65%);
  opacity: 0.55;
  animation: aurora-travel-2 28s cubic-bezier(0.42, 0, 0.58, 1) infinite,
             aurora-pulse-b 11s ease-in-out infinite;
}

.na-bg-aurora__orb--3 {
  /* Indigo */
  width: 48vw;
  height: 48vw;
  background: radial-gradient(circle at 50% 50%,
    #5B5BFF 0%,
    transparent 60%);
  opacity: 0.55;
  animation: aurora-travel-3 19s cubic-bezier(0.45, 0, 0.55, 1) infinite,
             aurora-pulse-a 7s 2s ease-in-out infinite;
}

.na-bg-aurora__orb--4 {
  /* Bright blue */
  width: 42vw;
  height: 42vw;
  background: radial-gradient(circle at 50% 50%,
    #6E8BFF 0%,
    transparent 65%);
  opacity: 0.50;
  animation: aurora-travel-4 25s cubic-bezier(0.42, 0, 0.58, 1) infinite,
             aurora-pulse-b 8s 4s ease-in-out infinite;
}

/* Conic sweep crossing the viewport diagonally */
.na-bg-aurora__sweep {
  position: absolute;
  inset: -20%;
  background:
    conic-gradient(from 0deg at 50% 50%,
      transparent 0deg,
      rgba(91, 91, 255, 0.18) 60deg,
      rgba(122, 63, 228, 0.18) 140deg,
      transparent 220deg,
      rgba(110, 139, 255, 0.18) 300deg,
      transparent 360deg);
  filter: blur(70px);
  opacity: 0.65;
  mix-blend-mode: screen;
  animation: aurora-sweep 18s linear infinite;
  will-change: transform;
}

/* Subtle grain shimmer */
.na-bg-aurora__grain {
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(rgba(255, 255, 255, 0.06) 1px, transparent 1px);
  background-size: 3px 3px;
  opacity: 0.18;
  mix-blend-mode: overlay;
  animation: aurora-shimmer 4s ease-in-out infinite;
}

.na-bg-stars {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    radial-gradient(1px 1px at 20% 30%, rgba(255, 255, 255, 0.6) 50%, transparent 100%),
    radial-gradient(1px 1px at 70% 60%, rgba(255, 255, 255, 0.5) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 40% 80%, rgba(255, 255, 255, 0.7) 50%, transparent 100%),
    radial-gradient(1px 1px at 90% 20%, rgba(255, 255, 255, 0.55) 50%, transparent 100%),
    radial-gradient(1px 1px at 10% 70%, rgba(255, 255, 255, 0.45) 50%, transparent 100%),
    radial-gradient(1px 1px at 55% 15%, rgba(255, 255, 255, 0.5) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 80% 90%, rgba(255, 255, 255, 0.6) 50%, transparent 100%),
    radial-gradient(1px 1px at 30% 50%, rgba(255, 255, 255, 0.4) 50%, transparent 100%);
  background-size: 800px 800px;
  animation: aurora-twinkle 6s ease-in-out infinite;
}

[data-theme="light"] .na-bg-aurora__orb--1,
[data-theme="light"] .na-bg-aurora__orb--2 {
  opacity: 0.38;
}
[data-theme="light"] .na-bg-aurora__orb--3,
[data-theme="light"] .na-bg-aurora__orb--4 {
  opacity: 0.30;
}
[data-theme="light"] .na-bg-aurora__grain {
  mix-blend-mode: multiply;
  opacity: 0.10;
}
[data-theme="light"] .na-bg-stars { display: none; }

/* === Travelling keyframes ===
   Orbs drift through the viewport in continuous orbital paths.
   Coordinates are origin-anchored at top-left (0,0) so translate values
   place the orb's top-left corner; combined with the orb's vw size this
   gives a wrap-around feel across the whole screen.                  */

@keyframes aurora-travel-1 {
  0%   { transform: translate(-25vw, -20vh) scale(1); }
  20%  { transform: translate(60vw, -10vh) scale(1.10); }
  40%  { transform: translate(70vw, 50vh) scale(1.18); }
  60%  { transform: translate(20vw, 70vh) scale(1.05); }
  80%  { transform: translate(-30vw, 40vh) scale(1.12); }
  100% { transform: translate(-25vw, -20vh) scale(1); }
}

@keyframes aurora-travel-2 {
  0%   { transform: translate(70vw, 60vh) scale(1); }
  20%  { transform: translate(-10vw, 70vh) scale(1.10); }
  40%  { transform: translate(-30vw, 10vh) scale(1.18); }
  60%  { transform: translate(40vw, -20vh) scale(1.05); }
  80%  { transform: translate(80vw, 20vh) scale(1.14); }
  100% { transform: translate(70vw, 60vh) scale(1); }
}

@keyframes aurora-travel-3 {
  0%   { transform: translate(40vw, -10vh) scale(1) rotate(0deg); }
  25%  { transform: translate(80vw, 35vh) scale(1.10) rotate(45deg); }
  50%  { transform: translate(35vw, 75vh) scale(1.18) rotate(90deg); }
  75%  { transform: translate(-10vw, 30vh) scale(1.06) rotate(135deg); }
  100% { transform: translate(40vw, -10vh) scale(1) rotate(180deg); }
}

@keyframes aurora-travel-4 {
  0%   { transform: translate(-15vw, 50vh) scale(1); }
  25%  { transform: translate(30vw, 70vh) scale(1.08); }
  50%  { transform: translate(75vw, 20vh) scale(1.16); }
  75%  { transform: translate(40vw, -15vh) scale(1.04); }
  100% { transform: translate(-15vw, 50vh) scale(1); }
}

@keyframes aurora-pulse-a {
  0%, 100% { opacity: 0.45; }
  50%      { opacity: 0.75; }
}

@keyframes aurora-pulse-b {
  0%, 100% { opacity: 0.35; }
  50%      { opacity: 0.65; }
}

@keyframes aurora-sweep {
  0%   { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

@keyframes aurora-shimmer {
  0%, 100% { opacity: 0.14; }
  50%      { opacity: 0.26; }
}

@keyframes aurora-twinkle {
  0%, 100% { opacity: 0.85; transform: translate3d(0, 0, 0); }
  50%      { opacity: 1;    transform: translate3d(0, -3px, 0); }
}

@media (prefers-reduced-motion: reduce) {
  .na-bg-aurora__orb,
  .na-bg-aurora__sweep,
  .na-bg-aurora__grain,
  .na-bg-stars {
    animation: none !important;
  }
}

/* ============================================================
   GLASS PRESETS
   ============================================================ */
.glass-soft,
.glass-medium,
.glass-strong {
  background-color: var(--na-color-glass-tint);
  border: 1px solid var(--na-color-glass-border);
  border-radius: var(--na-radius-lg);
  padding: var(--na-space-lg);
  box-shadow:
    inset 0 1px 0 var(--na-color-glass-highlight),
    var(--na-elev-3);
  transition: transform var(--na-motion-medium) var(--na-ease-out),
              box-shadow var(--na-motion-medium) var(--na-ease-out);
}

.glass-soft {
  -webkit-backdrop-filter: blur(var(--na-blur-sm)) saturate(140%);
  backdrop-filter: blur(var(--na-blur-sm)) saturate(140%);
}

.glass-medium {
  -webkit-backdrop-filter: blur(var(--na-blur-md)) saturate(160%);
  backdrop-filter: blur(var(--na-blur-md)) saturate(160%);
  box-shadow:
    inset 0 1px 0 var(--na-color-glass-highlight),
    var(--na-elev-4);
}

.glass-strong {
  -webkit-backdrop-filter: blur(var(--na-blur-lg)) saturate(180%);
  backdrop-filter: blur(var(--na-blur-lg)) saturate(180%);
  box-shadow:
    inset 0 1.5px 0 var(--na-color-glass-highlight),
    var(--na-elev-5);
}

@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .glass-soft, .glass-medium, .glass-strong {
    background-color: var(--na-color-surface-raised);
  }
}

@media (prefers-reduced-transparency: reduce) {
  .glass-soft, .glass-medium, .glass-strong {
    -webkit-backdrop-filter: blur(0);
    backdrop-filter: blur(0);
    background-color: var(--na-color-surface-raised);
  }
}

/* ============================================================
   LAYOUT — CONTAINER
   ============================================================ */
.na-container {
  width: 100%;
  margin-inline: auto;
  padding-inline: var(--na-space-lg);
}

@media (min-width: 768px) {
  .na-container {
    max-width: var(--na-container-tablet);
    padding-inline: var(--na-space-xl);
  }
}

@media (min-width: 1024px) {
  .na-container {
    max-width: var(--na-container-desktop);
    padding-inline: var(--na-space-2xl);
  }
}

/* ============================================================
   HEADER / TOP NAV
   ============================================================ */
.na-header {
  position: sticky;
  top: 0;
  z-index: 100;
  padding-block: var(--na-space-md);
  background: linear-gradient(180deg, var(--na-color-surface) 30%, transparent 100%);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
}

.na-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--na-space-md);
}

.na-brand {
  display: inline-flex;
  align-items: center;
  gap: var(--na-space-sm);
  color: var(--na-color-on-surface);
  font-weight: var(--na-weight-bold);
  letter-spacing: var(--na-tracking-snug);
  font-size: var(--na-text-body-md);
}

.na-brand__mark {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

.na-brand__name {
  display: inline-flex;
  flex-direction: column;
  line-height: 1.1;
}

.na-brand__sub {
  font-size: 10px;
  font-weight: var(--na-weight-medium);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--na-color-primary-300);
}

.na-nav-top {
  display: none;
}

@media (min-width: 1024px) {
  .na-nav-top {
    display: flex;
    gap: var(--na-space-xl);
  }
  .na-nav-top a {
    color: var(--na-color-on-surface-muted);
    font-weight: var(--na-weight-medium);
    font-size: var(--na-text-body-sm);
    padding: var(--na-space-sm) var(--na-space-md);
    border-radius: var(--na-radius-pill);
    transition: color var(--na-motion-fast) var(--na-ease-out),
                background var(--na-motion-fast) var(--na-ease-out);
  }
  .na-nav-top a:hover {
    color: var(--na-color-on-surface);
    background: var(--na-color-glass-tint);
  }
}

.na-header__actions {
  display: flex;
  align-items: center;
  gap: var(--na-space-sm);
}

/* ============================================================
   ICON BUTTON
   ============================================================ */
.na-icon-button {
  width: 44px;
  height: 44px;
  min-width: 44px;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--na-radius-pill);
  background: var(--na-color-glass-tint);
  border: 1px solid var(--na-color-glass-border);
  color: var(--na-color-on-surface);
  transition: background var(--na-motion-fast) var(--na-ease-out),
              transform var(--na-motion-fast) var(--na-ease-out);
}

.na-icon-button:hover {
  background: var(--na-color-glass-highlight);
}

.na-icon-button:active {
  transform: scale(0.96);
}

.na-icon-button svg {
  width: 20px;
  height: 20px;
  stroke: currentColor;
}

.na-icon-button [data-theme-icon-light] { display: none; }
[data-theme="light"] .na-icon-button [data-theme-icon-dark] { display: none; }
[data-theme="light"] .na-icon-button [data-theme-icon-light] { display: inline-block; }

/* ============================================================
   BUTTON
   ============================================================ */
.na-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--na-space-sm);
  min-height: 44px;
  padding: var(--na-space-md) var(--na-space-xl);
  border-radius: var(--na-radius-pill);
  font-weight: var(--na-weight-semibold);
  font-size: var(--na-text-body-md);
  letter-spacing: var(--na-tracking-snug);
  text-decoration: none;
  transition: transform var(--na-motion-fast) var(--na-ease-out),
              box-shadow var(--na-motion-fast) var(--na-ease-out),
              background var(--na-motion-fast) var(--na-ease-out);
}

.na-button--primary {
  background: linear-gradient(135deg,
    var(--na-color-primary-500) 0%,
    var(--na-color-accent-500) 100%);
  color: var(--na-color-neutral-0);
  box-shadow: 0 4px 18px 0 rgba(110, 139, 255, 0.45);
}

.na-button--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 26px 0 rgba(110, 139, 255, 0.55);
  color: var(--na-color-neutral-0);
}

.na-button--primary:active {
  transform: translateY(0);
}

.na-button--ghost {
  background: var(--na-color-glass-tint);
  border: 1px solid var(--na-color-glass-border);
  color: var(--na-color-on-surface);
  -webkit-backdrop-filter: blur(var(--na-blur-sm));
  backdrop-filter: blur(var(--na-blur-sm));
}

.na-button--ghost:hover {
  background: var(--na-color-glass-highlight);
  color: var(--na-color-on-surface);
}

.na-button svg {
  width: 18px;
  height: 18px;
  stroke: currentColor;
}

/* ============================================================
   BADGE / CHIP
   ============================================================ */
.na-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--na-space-xs);
  padding: var(--na-space-xs) var(--na-space-md);
  border-radius: var(--na-radius-pill);
  font-size: var(--na-text-caption);
  font-weight: var(--na-weight-medium);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  background: var(--na-color-glass-tint);
  border: 1px solid var(--na-color-glass-border);
  color: var(--na-color-on-surface-muted);
}

.na-badge--primary {
  color: var(--na-color-primary-300);
  border-color: rgba(143, 168, 255, 0.35);
}

.na-badge__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--na-color-success-500);
  box-shadow: 0 0 0 4px rgba(46, 194, 126, 0.18);
}

/* ============================================================
   HERO
   ============================================================ */
.na-hero {
  position: relative;
  padding-block: var(--na-space-3xl) var(--na-space-2xl);
}

.na-hero__inner {
  display: grid;
  gap: var(--na-space-2xl);
  align-items: center;
}

@media (min-width: 1024px) {
  .na-hero {
    padding-block: var(--na-space-4xl) var(--na-space-3xl);
  }
  .na-hero__inner {
    grid-template-columns: 1.05fr 0.95fr;
    gap: var(--na-space-3xl);
  }
}

.na-hero__badge {
  display: inline-flex;
}

.na-hero__title {
  margin-block: var(--na-space-lg) var(--na-space-md);
  font-size: clamp(2rem, 6vw + 0.5rem, var(--na-text-display));
  line-height: var(--na-leading-tight);
  letter-spacing: var(--na-tracking-tight);
  font-weight: var(--na-weight-bold);
}

.na-hero__title em {
  font-style: normal;
  background: linear-gradient(135deg,
    var(--na-color-primary-300) 0%,
    var(--na-color-accent-300) 50%,
    var(--na-color-secondary-300) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.na-hero__lede {
  font-size: var(--na-text-body-lg);
  line-height: var(--na-leading-relaxed);
  color: var(--na-color-on-surface-muted);
  max-width: 56ch;
  margin-bottom: var(--na-space-xl);
}

.na-hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--na-space-md);
}

.na-hero__stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--na-space-md);
  margin-top: var(--na-space-2xl);
  padding-top: var(--na-space-xl);
  border-top: 1px solid var(--na-color-glass-border);
}

.na-stat__value {
  display: block;
  font-size: var(--na-text-heading-sm);
  font-weight: var(--na-weight-bold);
  color: var(--na-color-on-surface);
  letter-spacing: var(--na-tracking-tight);
  line-height: 1.1;
}

.na-stat__label {
  display: block;
  margin-top: var(--na-space-xs);
  font-size: var(--na-text-caption);
  color: var(--na-color-on-surface-muted);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.na-hero__visual {
  position: relative;
  aspect-ratio: 1 / 1;
  max-width: 560px;
  margin-inline: auto;
  width: 100%;
}

.na-hero__orbit {
  position: absolute;
  inset: 0;
}

.na-hero__card {
  position: absolute;
  bottom: 8%;
  left: 50%;
  transform: translateX(-50%);
  width: min(86%, 360px);
  padding: var(--na-space-lg);
  display: flex;
  align-items: center;
  gap: var(--na-space-md);
}

.na-hero__card-icon {
  width: 48px;
  height: 48px;
  flex-shrink: 0;
  border-radius: var(--na-radius-md);
  background: linear-gradient(135deg,
    var(--na-color-primary-500),
    var(--na-color-accent-500));
  display: grid;
  place-items: center;
  color: var(--na-color-neutral-0);
}

.na-hero__card-icon svg {
  width: 24px;
  height: 24px;
  stroke: currentColor;
}

.na-hero__card-title {
  font-size: var(--na-text-body-md);
  font-weight: var(--na-weight-semibold);
  color: var(--na-color-on-surface);
  margin-bottom: 2px;
}

.na-hero__card-meta {
  font-size: var(--na-text-caption);
  color: var(--na-color-on-surface-muted);
  letter-spacing: 0.04em;
}

/* ============================================================
   SECTION — FEATURES
   ============================================================ */
.na-section {
  padding-block: var(--na-space-3xl);
}

@media (min-width: 1024px) {
  .na-section {
    padding-block: var(--na-space-4xl);
  }
}

.na-section__head {
  max-width: 720px;
  margin-bottom: var(--na-space-2xl);
}

.na-section__eyebrow {
  display: inline-block;
  font-size: var(--na-text-caption);
  font-weight: var(--na-weight-semibold);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--na-color-primary-300);
  margin-bottom: var(--na-space-md);
}

.na-section__title {
  font-size: clamp(1.75rem, 3.2vw + 0.5rem, var(--na-text-heading-lg));
  letter-spacing: var(--na-tracking-tight);
  margin-bottom: var(--na-space-md);
}

.na-section__lede {
  color: var(--na-color-on-surface-muted);
  font-size: var(--na-text-body-md);
  line-height: var(--na-leading-relaxed);
}

.na-grid {
  display: grid;
  gap: var(--na-space-lg);
}

.na-grid--features {
  grid-template-columns: 1fr;
}

@media (min-width: 600px) {
  .na-grid--features {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .na-grid--features {
    grid-template-columns: repeat(4, 1fr);
  }
}

.na-feature {
  padding: var(--na-space-xl);
  display: flex;
  flex-direction: column;
  gap: var(--na-space-md);
  height: 100%;
}

.na-feature__icon {
  width: 48px;
  height: 48px;
  border-radius: var(--na-radius-md);
  display: grid;
  place-items: center;
  background: var(--na-color-glass-tint);
  border: 1px solid var(--na-color-glass-border);
  color: var(--na-color-primary-300);
}

.na-feature__icon svg {
  width: 24px;
  height: 24px;
  stroke: currentColor;
}

.na-feature__title {
  font-size: var(--na-text-body-lg);
  font-weight: var(--na-weight-semibold);
  color: var(--na-color-on-surface);
}

.na-feature__desc {
  color: var(--na-color-on-surface-muted);
  font-size: var(--na-text-body-sm);
  line-height: var(--na-leading-relaxed);
}

/* ============================================================
   PILLARS (4 paradigms)
   ============================================================ */
.na-pillars {
  display: grid;
  gap: var(--na-space-md);
}

@media (min-width: 768px) {
  .na-pillars {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .na-pillars {
    grid-template-columns: repeat(4, 1fr);
  }
}

.na-pillar {
  padding: var(--na-space-xl);
  position: relative;
  overflow: hidden;
}

.na-pillar::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--na-color-primary-500), transparent);
  opacity: 0.6;
}

.na-pillar__num {
  font-family: var(--na-font-mono);
  font-size: var(--na-text-caption);
  font-weight: var(--na-weight-medium);
  color: var(--na-color-on-surface-muted);
  letter-spacing: 0.1em;
  margin-bottom: var(--na-space-md);
}

.na-pillar__title {
  font-size: var(--na-text-body-lg);
  font-weight: var(--na-weight-semibold);
  color: var(--na-color-on-surface);
  margin-bottom: var(--na-space-sm);
}

.na-pillar__desc {
  color: var(--na-color-on-surface-muted);
  font-size: var(--na-text-body-sm);
  line-height: var(--na-leading-relaxed);
}

/* ============================================================
   COURSES PREVIEW
   ============================================================ */
.na-courses {
  display: grid;
  gap: var(--na-space-lg);
}

@media (min-width: 768px) {
  .na-courses {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .na-courses {
    grid-template-columns: repeat(3, 1fr);
  }
}

.na-course {
  padding: 0;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.na-course__cover {
  aspect-ratio: 16 / 9;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--na-color-glass-border);
}

.na-course__cover svg {
  width: 100%;
  height: 100%;
}

.na-course__body {
  padding: var(--na-space-lg);
  display: flex;
  flex-direction: column;
  gap: var(--na-space-sm);
  flex: 1;
}

.na-course__meta {
  display: flex;
  gap: var(--na-space-sm);
  flex-wrap: wrap;
  font-size: var(--na-text-caption);
  color: var(--na-color-on-surface-muted);
  letter-spacing: 0.04em;
}

.na-course__title {
  font-size: var(--na-text-body-lg);
  font-weight: var(--na-weight-semibold);
  color: var(--na-color-on-surface);
}

.na-course__desc {
  color: var(--na-color-on-surface-muted);
  font-size: var(--na-text-body-sm);
  line-height: var(--na-leading-relaxed);
  flex: 1;
}

.na-course__progress {
  height: 6px;
  border-radius: var(--na-radius-pill);
  background: var(--na-color-glass-tint);
  overflow: hidden;
  margin-top: var(--na-space-sm);
}

.na-course__progress-fill {
  display: block;
  height: 100%;
  background: linear-gradient(90deg,
    var(--na-color-primary-500),
    var(--na-color-accent-500));
  border-radius: inherit;
}

/* ============================================================
   CTA BANNER
   ============================================================ */
.na-cta {
  padding: clamp(var(--na-space-2xl), 6vw, var(--na-space-4xl));
  text-align: center;
  position: relative;
  overflow: hidden;
}

.na-cta::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 20%, var(--na-color-primary-500) 0%, transparent 40%),
    radial-gradient(circle at 80% 80%, var(--na-color-accent-500) 0%, transparent 40%);
  opacity: 0.18;
  z-index: -1;
}

.na-cta__title {
  font-size: clamp(1.75rem, 4vw + 0.5rem, var(--na-text-heading-lg));
  letter-spacing: var(--na-tracking-tight);
  margin-bottom: var(--na-space-md);
}

.na-cta__lede {
  color: var(--na-color-on-surface-muted);
  font-size: var(--na-text-body-md);
  margin-inline: auto;
  margin-bottom: var(--na-space-xl);
  max-width: 56ch;
}

.na-cta__actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--na-space-md);
}

/* ============================================================
   FOOTER
   ============================================================ */
.na-footer {
  padding-block: var(--na-space-2xl) var(--na-space-xl);
  border-top: 1px solid var(--na-color-glass-border);
  margin-top: var(--na-space-2xl);
}

.na-footer__inner {
  display: grid;
  gap: var(--na-space-xl);
}

@media (min-width: 768px) {
  .na-footer__inner {
    grid-template-columns: 1.4fr repeat(3, 1fr);
  }
}

.na-footer__intro p {
  color: var(--na-color-on-surface-muted);
  font-size: var(--na-text-body-sm);
  line-height: var(--na-leading-relaxed);
  margin-top: var(--na-space-md);
  max-width: 38ch;
}

.na-footer__col-title {
  font-size: var(--na-text-caption);
  font-weight: var(--na-weight-semibold);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--na-color-on-surface);
  margin-bottom: var(--na-space-md);
}

.na-footer__list a {
  display: inline-block;
  color: var(--na-color-on-surface-muted);
  font-size: var(--na-text-body-sm);
  padding-block: var(--na-space-xs);
  transition: color var(--na-motion-fast) var(--na-ease-out);
}

.na-footer__list a:hover {
  color: var(--na-color-on-surface);
}

.na-footer__bottom {
  margin-top: var(--na-space-xl);
  padding-top: var(--na-space-lg);
  border-top: 1px solid var(--na-color-glass-border);
  display: flex;
  flex-wrap: wrap;
  gap: var(--na-space-md);
  justify-content: space-between;
  font-size: var(--na-text-caption);
  color: var(--na-color-on-surface-dim);
}

/* ============================================================
   BOTTOM FLOATING NAV (mobile)
   ============================================================ */
.na-bottom-floating {
  position: fixed;
  left: 50%;
  bottom: max(var(--na-space-md), env(safe-area-inset-bottom, 0px));
  transform: translateX(-50%);
  z-index: 90;
  display: flex;
  gap: var(--na-space-2xs);
  padding: var(--na-space-xs);
  border-radius: var(--na-radius-pill);
  background: var(--na-color-glass-tint);
  border: 1px solid var(--na-color-glass-border);
  -webkit-backdrop-filter: blur(var(--na-blur-md)) saturate(160%);
  backdrop-filter: blur(var(--na-blur-md)) saturate(160%);
  box-shadow: var(--na-elev-4);
}

.na-bottom-floating__item {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: var(--na-radius-pill);
  color: var(--na-color-on-surface-muted);
  transition: color var(--na-motion-fast) var(--na-ease-out),
              background var(--na-motion-fast) var(--na-ease-out);
}

.na-bottom-floating__item:hover,
.na-bottom-floating__item[aria-current="page"] {
  color: var(--na-color-on-surface);
  background: var(--na-color-glass-highlight);
}

.na-bottom-floating__item svg {
  width: 22px;
  height: 22px;
  stroke: currentColor;
}

@media (min-width: 1024px) {
  .na-bottom-floating { display: none; }
}

/* ============================================================
   HELPERS
   ============================================================ */
.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;
}

[hidden] { display: none !important; }

/* ============================================================
   REDUCED MOTION
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0ms !important;
    scroll-behavior: auto !important;
  }
}