/* =========================================
   KARTINO — Landing Page Styles
   ========================================= */

/* --- Palette Variables --- */
:root {
  --primary: #E07A5F;
  --primary-dark: #c9614a;
  --secondary: #81B29A;
  --highlight: #F2CC8F;
  --bg: #F4F1DE;
  --bg-alt: #efe9d0;
  --text: #3D405B;
  --text-light: rgba(61,64,91,0.6);
  --card-bg: #ffffff;
  --card-shadow: rgba(61,64,91,0.08);
  --hero-gradient: linear-gradient(160deg, #F4F1DE 0%, #f7ede2 50%, #fdf6ee 100%);
  --primary-glow: rgba(224,122,95,0.18);
  --secondary-glow: rgba(129,178,154,0.15);
  --nav-bg: rgba(244,241,222,0.85);
  --border-subtle: rgba(61,64,91,0.06);
}

/* Palette Themes */
.palette-mediterranean {
  --primary: #00B4D8; --primary-dark: #0096b7; --secondary: #48CAE4; --highlight: #F4D35E;
  --bg: #FFFCF2; --bg-alt: #f0f8ff; --text: #023047; --text-light: rgba(2,48,71,0.55);
  --card-bg: #fff; --card-shadow: rgba(2,48,71,0.06);
  --hero-gradient: linear-gradient(160deg, #FFFCF2 0%, #e8f8ff 50%, #f0fbff 100%);
  --primary-glow: rgba(0,180,216,0.15); --secondary-glow: rgba(72,202,228,0.12);
  --nav-bg: rgba(255,252,242,0.85); --border-subtle: rgba(2,48,71,0.06);
}
.palette-sunset {
  --primary: #FF6B6B; --primary-dark: #e55555; --secondary: #FFA07A; --highlight: #FFD93D;
  --bg: #FFF8E7; --bg-alt: #fff0d6; --text: #2D3436; --text-light: rgba(45,52,54,0.55);
  --card-bg: #fff; --card-shadow: rgba(45,52,54,0.06);
  --hero-gradient: linear-gradient(160deg, #FFF8E7 0%, #fff0e0 50%, #fff5e8 100%);
  --primary-glow: rgba(255,107,107,0.15); --secondary-glow: rgba(255,160,122,0.12);
  --nav-bg: rgba(255,248,231,0.85); --border-subtle: rgba(45,52,54,0.06);
}
.palette-aurora {
  --primary: #7B2FF7; --primary-dark: #6422cc; --secondary: #5390D9; --highlight: #6BCB77;
  --bg: #1B1B2F; --bg-alt: #222244; --text: #E0E0FF; --text-light: rgba(224,224,255,0.55);
  --card-bg: rgba(255,255,255,0.06); --card-shadow: rgba(0,0,0,0.25);
  --hero-gradient: linear-gradient(160deg, #1B1B2F 0%, #27274a 50%, #1f1f3a 100%);
  --primary-glow: rgba(123,47,247,0.2); --secondary-glow: rgba(83,144,217,0.15);
  --nav-bg: rgba(27,27,47,0.88); --border-subtle: rgba(255,255,255,0.06);
  --secondary-button-text: #43396f;
  --secondary-button-note-bg: rgba(123,47,247,0.1);
  --secondary-button-note-border: rgba(123,47,247,0.18);
  --secondary-button-note-text: #5f2ae2;
}


/* --- Reset & Base --- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  transition: background 0.5s ease, color 0.5s ease;
  overflow-x: hidden;
  line-height: 1.6;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
button { cursor: pointer; font-family: inherit; }


/* --- Scroll Animations --- */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.7s cubic-bezier(0.22,1,0.36,1), transform 0.7s cubic-bezier(0.22,1,0.36,1);
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }
.reveal-delay-5 { transition-delay: 0.5s; }


/* --- Navigation --- */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 40px;
  background: transparent;
  transition: background 0.4s ease, box-shadow 0.4s ease, padding 0.4s ease;
}
.nav.scrolled {
  background: rgba(244,241,222,0.45);
  backdrop-filter: blur(24px) saturate(1.4); -webkit-backdrop-filter: blur(24px) saturate(1.4);
  box-shadow: 0 1px 0 var(--border-subtle), 0 4px 20px rgba(61,64,91,0.04);
  padding: 12px 40px;
}
.nav-brand {
  display: flex; align-items: center; gap: 12px;
}
.nav-logo {
  width: 42px; height: 42px; border-radius: 12px;
  object-fit: cover;
  transition: transform 0.3s ease;
}
.nav-logo:hover { transform: scale(1.08) rotate(-3deg); }
.nav-brand-name {
  font-family: 'Outfit', sans-serif; font-weight: 700; font-size: 22px;
  color: var(--text); letter-spacing: -0.5px;
}
.nav-links {
  display: flex; align-items: center; gap: 32px;
  list-style: none;
}
.nav-links a {
  font-size: 15px; font-weight: 500; color: var(--text-light);
  transition: color 0.3s ease;
}
.nav-links a:hover { color: var(--text); }
.nav-cta,
.btn-primary,
.btn-secondary {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  isolation: isolate;
  overflow: hidden;
  transition:
    transform 0.28s cubic-bezier(0.22, 1, 0.36, 1),
    box-shadow 0.28s cubic-bezier(0.22, 1, 0.36, 1),
    border-color 0.28s ease,
    background 0.28s ease,
    color 0.28s ease;
}
.nav-cta > *,
.btn-primary > *,
.btn-secondary > * {
  transition:
    transform 0.32s cubic-bezier(0.22, 1, 0.36, 1),
    opacity 0.28s ease,
    background 0.28s ease,
    border-color 0.28s ease,
    box-shadow 0.28s ease;
}
.nav-cta::before,
.btn-primary::before,
.btn-secondary::before {
  content: '';
  position: absolute;
  inset: 1px;
  border-radius: inherit;
  pointer-events: none;
  transition:
    opacity 0.32s ease,
    transform 0.42s cubic-bezier(0.22, 1, 0.36, 1);
}
.btn-text,
.btn-note,
.btn-mark {
  position: relative;
  z-index: 1;
}
.nav-cta {
  padding: 8px 10px 8px 20px; border-radius: 999px; border: 1px solid rgba(255,255,255,0.18);
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 52%, #eb967d 100%);
  color: #fff;
  font-family: 'Outfit', sans-serif; font-weight: 600; font-size: 15px;
  box-shadow: 0 10px 30px rgba(224,122,95,0.22);
}
.nav-cta::before,
.btn-primary::before {
  background:
    linear-gradient(115deg, rgba(255,255,255,0.28) 0%, rgba(255,255,255,0.08) 32%, rgba(255,255,255,0) 58%),
    linear-gradient(180deg, rgba(255,255,255,0.08), rgba(255,255,255,0));
}
.nav-cta:hover {
  transform: translateY(-2px) scale(1.01);
  box-shadow: 0 16px 34px rgba(224,122,95,0.28);
}
.nav-cta:hover::before,
.btn-primary:hover::before {
  transform: translateX(10px);
}
.nav-mobile-toggle {
  display: none;
  background: none; border: none;
  width: 36px; height: 36px;
  flex-direction: column; justify-content: center; gap: 5px; align-items: center;
}
.nav-mobile-toggle span {
  display: block; width: 22px; height: 2px;
  background: var(--text); border-radius: 2px;
  transition: all 0.3s ease;
}


/* --- Hero --- */
.hero {
  min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  padding: 120px 40px 80px;
  background: var(--hero-gradient);
  position: relative; overflow: hidden;
}
.hero-container {
  display: flex; align-items: center; justify-content: space-between;
  max-width: 1200px; width: 100%; gap: 60px;
}
.hero-content { flex: 1; max-width: 600px; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 8px 18px; border-radius: 50px; font-size: 14px;
  font-weight: 500; margin-bottom: 28px;
  background: var(--primary-glow); color: var(--primary);
  border: 1px solid rgba(224,122,95,0.2);
}
.hero h1 {
  font-family: 'Outfit', sans-serif; font-weight: 800;
  font-size: clamp(40px, 5.5vw, 68px); line-height: 1.08;
  margin-bottom: 20px; letter-spacing: -2px;
}
.hero h1 .accent {
  color: var(--primary);
  position: relative;
}
.hero h1 .accent::after {
  content: '';
  position: absolute; bottom: 2px; left: 0; right: 0;
  height: 6px; background: var(--primary-glow);
  border-radius: 3px; z-index: -1;
}
.hero-sub {
  font-size: 18px; line-height: 1.7; color: var(--text-light);
  max-width: 480px; margin-bottom: 36px;
}
.hero-cta-group {
  display: flex; gap: 16px; flex-wrap: wrap; align-items: center;
}
.btn-primary {
  padding: 12px 14px 12px 28px; border-radius: 999px; border: 1px solid rgba(255,255,255,0.2);
  font-family: 'Outfit', sans-serif; font-weight: 600; font-size: 17px;
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 50%, #eb967d 100%);
  color: #fff;
  box-shadow: 0 18px 38px rgba(224,122,95,0.24), 0 6px 18px rgba(224,122,95,0.14);
}
.btn-primary:hover {
  transform: translateY(-3px) scale(1.01);
  box-shadow: 0 24px 44px rgba(224,122,95,0.3), 0 8px 24px rgba(224,122,95,0.18);
}
.btn-secondary {
  padding: 14px 18px 14px 24px; border-radius: 26px;
  font-family: 'Outfit', sans-serif; font-weight: 600; font-size: 17px;
  background: rgba(255,255,255,0.72); color: var(--secondary-button-text, var(--text));
  border: 1px solid rgba(61,64,91,0.1);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 14px 32px rgba(61,64,91,0.08), inset 0 1px 0 rgba(255,255,255,0.82);
}
.btn-secondary::before {
  background:
    linear-gradient(180deg, rgba(255,255,255,0.7) 0%, rgba(255,255,255,0.12) 100%),
    radial-gradient(circle at top right, rgba(242,204,143,0.32), rgba(242,204,143,0) 44%);
}
.btn-secondary:hover {
  border-color: rgba(224,122,95,0.24);
  transform: translateY(-3px);
  box-shadow: 0 20px 38px rgba(61,64,91,0.1), inset 0 1px 0 rgba(255,255,255,0.92);
}
.btn-secondary:hover::before {
  transform: translateY(-2px) scale(1.02);
}
.nav-cta:hover .btn-text,
.btn-primary:hover .btn-text {
  transform: translateX(-2px);
}
.btn-secondary:hover .btn-text {
  transform: translateX(-1px);
}
.nav-cta:focus-visible,
.btn-primary:focus-visible,
.btn-secondary:focus-visible {
  outline: none;
  box-shadow:
    0 0 0 4px rgba(242,204,143,0.35),
    0 16px 34px rgba(61,64,91,0.12);
}
.btn-mark {
  width: 42px;
  height: 42px;
  flex-shrink: 0;
  position: relative;
  border-radius: 16px;
  border: 1px solid rgba(255,255,255,0.2);
  background:
    radial-gradient(circle at 72% 28%, var(--highlight) 0 2px, transparent 3px),
    linear-gradient(180deg, rgba(255,255,255,0.26), rgba(255,255,255,0.08));
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.18);
  transform: rotate(0deg) translateX(0);
}
.btn-mark::before,
.btn-mark::after {
  content: '';
  position: absolute;
  border-radius: 5px;
  top: 11px;
  transform-origin: center;
  transition:
    transform 0.34s cubic-bezier(0.22, 1, 0.36, 1),
    box-shadow 0.28s ease,
    background 0.28s ease;
}
.btn-mark::before {
  left: 11px;
  width: 13px;
  height: 16px;
  background: rgba(255,255,255,0.72);
  transform: rotate(-16deg);
}
.btn-mark::after {
  left: 18px;
  width: 14px;
  height: 18px;
  background: linear-gradient(180deg, #ffffff 0%, #fff7ef 100%);
  transform: rotate(8deg);
  box-shadow: 0 6px 12px rgba(61,64,91,0.14);
}
.nav-cta:hover .btn-mark,
.btn-primary:hover .btn-mark {
  transform: rotate(6deg) translateX(2px) translateY(-1px);
}
.nav-cta:hover .btn-mark::before,
.btn-primary:hover .btn-mark::before {
  transform: translateX(-3px) rotate(-28deg);
}
.nav-cta:hover .btn-mark::after,
.btn-primary:hover .btn-mark::after {
  transform: translateX(3px) rotate(16deg);
  box-shadow: 0 9px 18px rgba(61,64,91,0.18);
}
.btn-note {
  padding: 6px 10px;
  border-radius: 999px;
  font-size: 11px;
  line-height: 1;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--secondary-button-note-text, var(--primary-dark));
  background: var(--secondary-button-note-bg, rgba(224,122,95,0.12));
  border: 1px solid var(--secondary-button-note-border, rgba(224,122,95,0.12));
}
.btn-secondary:hover .btn-note {
  transform: translateX(2px) translateY(-1px);
  background: var(--secondary-button-note-bg, rgba(224,122,95,0.18));
  border-color: var(--secondary-button-note-border, rgba(224,122,95,0.2));
  box-shadow: 0 6px 14px rgba(224,122,95,0.12);
}
.hero-character {
  flex: 0 0 auto;
  position: relative;
}
.hero-character img {
  width: 320px; height: auto;
  animation: heroFloat 4s ease-in-out infinite;
  filter: drop-shadow(0 20px 40px rgba(61,64,91,0.12));
}
.hero-speech {
  position: absolute; top: -10px; left: -40px;
  background: var(--card-bg); color: var(--text);
  padding: 10px 18px; border-radius: 20px 20px 4px 20px;
  font-family: 'Outfit', sans-serif; font-weight: 600; font-size: 16px;
  box-shadow: 0 4px 20px var(--card-shadow);
  animation: speechPop 0.5s cubic-bezier(0.34,1.56,0.64,1) 1.2s both;
  white-space: nowrap;
}
@keyframes heroFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-14px); }
}
@keyframes speechPop {
  from { opacity: 0; transform: scale(0.5) translateY(10px); }
  to { opacity: 1; transform: scale(1) translateY(0); }
}

/* Hero sparkle particles */
.sparkle-container {
  position: absolute; inset: 0; pointer-events: none; overflow: hidden;
}
.sparkle {
  position: absolute;
  width: 8px; height: 8px;
  background: var(--highlight);
  border-radius: 50%;
  opacity: 0;
  animation: sparkleFloat linear infinite;
}
.sparkle:nth-child(1) { left: 10%; top: 20%; animation-duration: 8s; animation-delay: 0s; }
.sparkle:nth-child(2) { left: 85%; top: 15%; animation-duration: 10s; animation-delay: 2s; width: 6px; height: 6px; background: var(--primary); }
.sparkle:nth-child(3) { left: 70%; top: 60%; animation-duration: 12s; animation-delay: 4s; width: 5px; height: 5px; background: var(--secondary); }
.sparkle:nth-child(4) { left: 25%; top: 75%; animation-duration: 9s; animation-delay: 1s; width: 7px; height: 7px; }
.sparkle:nth-child(5) { left: 50%; top: 30%; animation-duration: 11s; animation-delay: 3s; width: 4px; height: 4px; background: var(--primary); }
@keyframes sparkleFloat {
  0% { opacity: 0; transform: translateY(0) scale(0); }
  20% { opacity: 0.6; transform: translateY(-20px) scale(1); }
  80% { opacity: 0.4; transform: translateY(-80px) scale(0.8); }
  100% { opacity: 0; transform: translateY(-120px) scale(0); }
}


/* --- Features --- */
.features {
  padding: 100px 40px 120px;
  max-width: 1200px; margin: 0 auto;
}
.section-header {
  text-align: center; margin-bottom: 64px;
}
.section-header h2 {
  font-family: 'Outfit', sans-serif; font-weight: 700;
  font-size: clamp(28px, 4vw, 40px); margin-bottom: 14px; letter-spacing: -0.5px;
}
.section-header p {
  color: var(--text-light); font-size: 18px; max-width: 500px;
  margin: 0 auto; line-height: 1.6;
}
.features-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
}
.feature-card {
  background: var(--card-bg); border-radius: 20px; padding: 32px 28px;
  box-shadow: 0 2px 16px var(--card-shadow);
  transition: all 0.4s cubic-bezier(0.22,1,0.36,1);
  border: 1px solid var(--border-subtle);
  position: relative; overflow: hidden;
}
.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 40px var(--card-shadow);
}
.feature-icon {
  width: 52px; height: 52px; border-radius: 14px;
  display: flex; align-items: center; justify-content: center;
  font-size: 26px; margin-bottom: 18px;
  background: var(--primary-glow);
}
.feature-card h3 {
  font-family: 'Outfit', sans-serif; font-weight: 600;
  font-size: 19px; margin-bottom: 10px;
}
.feature-card p {
  color: var(--text-light); font-size: 15px; line-height: 1.65;
}
.feature-card .feature-sticker {
  position: absolute; bottom: -4px; right: -4px;
  width: 56px; height: 56px;
  opacity: 0.12;
  transition: opacity 0.4s ease, transform 0.4s ease;
  pointer-events: none;
}
.feature-card:hover .feature-sticker,
.feature-card.in-view .feature-sticker {
  opacity: 0.25;
  transform: translate(-8px, -8px) scale(1.9) rotate(-5deg);
}


/* --- How It Works (Chat Demo) --- */
.how-section {
  padding: 100px 40px 120px;
  background: var(--hero-gradient);
}
.how-container {
  max-width: 1200px; margin: 0 auto;
}
.how-layout {
  display: flex; align-items: flex-start; gap: 80px;
}
.how-text { flex: 1; padding-top: 40px; }
.how-steps {
  display: flex; flex-direction: column; gap: 36px; margin-top: 48px;
}
.how-step {
  display: flex; gap: 20px; align-items: flex-start;
}
.how-step-number {
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--primary); color: #fff;
  font-family: 'Outfit', sans-serif; font-weight: 700; font-size: 18px;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.how-step-content h4 {
  font-family: 'Outfit', sans-serif; font-weight: 600;
  font-size: 17px; margin-bottom: 4px;
}
.how-step-content p {
  color: var(--text-light); font-size: 15px; line-height: 1.6;
}

/* Chat Demo */
.chat-demo-wrapper { flex: 1; max-width: 420px; }
.chat-demo {
  background: #212121; border-radius: 20px; overflow: hidden;
  box-shadow: 0 20px 60px rgba(0,0,0,0.25);
  font-family: 'Inter', sans-serif;
}
.chat-header {
  display: flex; align-items: center; gap: 12px;
  padding: 14px 18px;
  background: #1a1a1a;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}
.chat-avatar {
  width: 36px; height: 36px; border-radius: 50%;
  object-fit: cover;
}
.chat-header-info {
  display: flex; flex-direction: column;
}
.chat-header-name {
  color: #fff; font-weight: 600; font-size: 14px;
}
.chat-header-status {
  color: rgba(255,255,255,0.4); font-size: 12px;
}
.chat-body {
  padding: 20px 16px; min-height: 380px;
  display: flex; flex-direction: column; gap: 10px;
}
.chat-msg {
  max-width: 85%; padding: 10px 14px;
  border-radius: 16px; font-size: 14px; line-height: 1.5;
  opacity: 0; transform: translateY(12px);
  transition: opacity 0.4s ease, transform 0.4s ease;
}
.chat-msg.visible {
  opacity: 1; transform: translateY(0);
}
.chat-msg.user {
  align-self: flex-end;
  background: #2B5278; color: #fff;
  border-bottom-right-radius: 4px;
}
.chat-msg.bot {
  align-self: flex-start;
  background: #2a2a2a; color: rgba(255,255,255,0.9);
  border-bottom-left-radius: 4px;
}
.chat-msg.bot.card {
  background: #2a2a2a; padding: 14px 16px;
  border: 1px solid rgba(255,255,255,0.08);
  border-radius: 16px;
}
.chat-card-flag { font-size: 12px; opacity: 0.5; margin-bottom: 4px; color: rgba(255,255,255,0.6); }
.chat-card-word {
  font-family: 'Outfit', sans-serif; font-weight: 700;
  font-size: 20px; color: var(--primary); margin-bottom: 4px;
}
.chat-card-def { font-size: 13px; color: rgba(255,255,255,0.7); margin-bottom: 10px; line-height: 1.5; }
.chat-card-example {
  font-size: 13px; font-style: italic;
  color: rgba(255,255,255,0.5); padding: 8px 12px;
  background: rgba(255,255,255,0.04); border-radius: 10px;
  line-height: 1.5;
}
.chat-buttons {
  display: flex; gap: 8px; margin-top: 8px;
}
.chat-btn {
  padding: 6px 14px; border-radius: 8px;
  font-size: 13px; font-weight: 500; border: none;
  cursor: default;
}
.chat-btn.save { background: rgba(129,178,154,0.2); color: #81B29A; }
.chat-btn.regen { background: rgba(242,204,143,0.15); color: #F2CC8F; }
.chat-typing {
  align-self: flex-start;
  display: flex; gap: 4px; padding: 12px 18px;
  background: #2a2a2a; border-radius: 16px;
  opacity: 0;
  transition: opacity 0.3s ease;
}
.chat-typing.visible { opacity: 1; }
.chat-typing span {
  width: 7px; height: 7px; border-radius: 50%;
  background: rgba(255,255,255,0.3);
  animation: typingDot 1.4s infinite;
}
.chat-typing span:nth-child(2) { animation-delay: 0.2s; }
.chat-typing span:nth-child(3) { animation-delay: 0.4s; }
@keyframes typingDot {
  0%, 100% { opacity: 0.3; transform: scale(1); }
  50% { opacity: 0.8; transform: scale(1.2); }
}
.chat-divider {
  text-align: center; color: rgba(255,255,255,0.25);
  font-size: 12px; padding: 8px 0;
  opacity: 0; transition: opacity 0.4s ease;
}
.chat-divider.visible { opacity: 1; }
.chat-footer {
  display: flex; align-items: center; justify-content: center;
  padding: 14px; border-top: 1px solid rgba(255,255,255,0.06);
}
.chat-replay {
  background: none; border: none; color: rgba(255,255,255,0.4);
  font-size: 13px; font-weight: 500; display: flex; align-items: center; gap: 6px;
  transition: color 0.3s ease; cursor: pointer;
}
.chat-replay:hover { color: rgba(255,255,255,0.7); }


/* --- Flashcard Preview --- */
.preview-section {
  padding: 100px 40px 200px;
  max-width: 800px; margin: 0 auto; text-align: center;
}
.flashcard-container {
  perspective: 1200px;
  margin-top: 48px;
}
.flashcard {
  position: relative; width: 100%; max-width: 480px; margin: 0 auto;
  transform-style: preserve-3d;
  transition: transform 0.15s ease-out;
}
.flashcard-front, .flashcard-back {
  background: var(--card-bg); border-radius: 20px;
  padding: 32px 28px; text-align: left;
  box-shadow: 0 8px 40px var(--card-shadow);
  border: 1px solid var(--border-subtle);
  backface-visibility: hidden;
}
.flashcard-back {
  position: absolute; inset: 0;
  transform: rotateY(180deg);
  display: flex; flex-direction: column; justify-content: center; align-items: center;
  text-align: center;
}
.fc-back-emoji { font-size: 48px; margin-bottom: 16px; }
.flashcard-back h3 {
  font-family: 'Outfit', sans-serif; font-weight: 700;
  font-size: 28px; color: var(--secondary); margin-bottom: 12px;
}
.flashcard-back p {
  color: var(--text-light); font-size: 16px; line-height: 1.6; max-width: 360px;
}
.fc-header {
  display: flex; align-items: center; gap: 10px; margin-bottom: 14px;
}
.fc-flag { font-size: 20px; }
.fc-type {
  font-size: 13px; font-weight: 600; text-transform: uppercase;
  color: var(--text-light); letter-spacing: 1px;
}
.fc-definition {
  font-size: 15px; line-height: 1.7; margin-bottom: 16px;
  color: var(--text); padding: 12px 16px;
  background: var(--primary-glow); border-radius: 12px;
}
.fc-divider {
  height: 2px; border-radius: 1px; margin-bottom: 16px;
  background: var(--highlight); opacity: 0.3;
}
.fc-row {
  display: flex; align-items: baseline; gap: 8px;
  margin-bottom: 8px; font-size: 15px; line-height: 1.6;
}
.fc-label {
  font-weight: 600; white-space: nowrap; flex-shrink: 0;
}
.fc-word {
  font-family: 'Outfit', sans-serif; font-weight: 700;
  font-size: 20px; color: var(--primary);
}
.fc-lang-note {
  font-style: italic; color: var(--text-light); font-size: 14px;
}
.fc-example {
  font-size: 15px; color: var(--text);
  padding: 14px 18px; border-radius: 12px; margin-top: 12px;
  background: var(--secondary-glow); line-height: 1.7;
}
.fc-example-trans {
  display: block; margin-top: 4px;
  opacity: 0.55; font-style: italic;
}
.flip-hint {
  margin-top: 20px; font-size: 14px; color: var(--text-light);
  display: flex; align-items: center; justify-content: center; gap: 6px;
  animation: hintPulse 2s ease-in-out infinite;
}
@keyframes hintPulse {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 1; }
}


/* --- Who Is It For --- */
.personas-section {
  padding: 100px 40px 120px;
  background: var(--hero-gradient);
}
.personas-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px;
  max-width: 1000px; margin: 0 auto;
}
.persona-card {
  text-align: center; padding: 40px 28px;
  background: var(--card-bg); border-radius: 20px;
  border: 1px solid var(--border-subtle);
  box-shadow: 0 2px 16px var(--card-shadow);
  transition: all 0.4s ease;
}
.persona-card:hover { transform: translateY(-4px); }
.persona-emoji {
  font-size: 40px; margin-bottom: 16px; display: block;
}
.persona-card h3 {
  font-family: 'Outfit', sans-serif; font-weight: 600;
  font-size: 18px; margin-bottom: 8px;
}
.persona-card p {
  color: var(--text-light); font-size: 15px; line-height: 1.6;
}


/* --- Trust / Social Proof --- */
.trust-section {
  padding: 60px 40px;
  max-width: 900px; margin: 0 auto;
}
.trust-row {
  display: flex; justify-content: center; gap: 40px; flex-wrap: wrap;
}
.trust-item {
  display: flex; align-items: center; gap: 10px;
  font-size: 15px; font-weight: 500; color: var(--text-light);
}
.trust-item span { font-size: 20px; }


/* --- Final CTA --- */
.final-cta {
  padding: 100px 40px 120px;
  text-align: center;
  background: linear-gradient(180deg, var(--bg) 0%, var(--bg-alt) 100%);
  position: relative;
}
.final-cta-character {
  width: 180px; height: auto; margin: 0 auto 32px;
  animation: heroFloat 4s ease-in-out infinite;
  filter: drop-shadow(0 12px 30px rgba(61,64,91,0.1));
}
.final-cta h2 {
  font-family: 'Outfit', sans-serif; font-weight: 700;
  font-size: clamp(28px, 4vw, 40px); margin-bottom: 14px; letter-spacing: -0.5px;
}
.final-cta p {
  color: var(--text-light); font-size: 17px; margin-bottom: 36px;
}


/* --- Footer --- */
.footer {
  padding: 48px 40px 32px;
  border-top: 1px solid var(--border-subtle);
}
.footer-top {
  display: flex; justify-content: space-between; align-items: flex-start;
  max-width: 1200px; margin: 0 auto 32px;
  flex-wrap: wrap; gap: 24px;
}
.footer-brand {
  display: flex; align-items: center; gap: 10px;
}
.footer-logo { width: 32px; height: 32px; border-radius: 8px; }
.footer-brand-name {
  font-family: 'Outfit', sans-serif; font-weight: 700; font-size: 18px;
}
.footer-links {
  display: flex; gap: 28px; list-style: none;
}
.footer-links a {
  font-size: 14px; color: var(--text-light);
  transition: color 0.3s ease;
}
.footer-links a:hover { color: var(--text); }
.footer-bottom {
  text-align: center;
  padding-top: 24px;
  border-top: 1px solid var(--border-subtle);
  max-width: 1200px; margin: 0 auto;
}
.footer-bottom p {
  font-size: 13px; color: var(--text-light);
}

/* Palette Easter Egg */
.palette-egg {
  display: flex; align-items: center; justify-content: center;
  gap: 12px; margin-top: 16px;
}
.palette-egg-label {
  font-size: 13px; color: var(--text-light);
  cursor: pointer; display: flex; align-items: center; gap: 6px;
  transition: color 0.3s ease;
}
.palette-egg-label:hover { color: var(--text); }
.palette-dots {
  display: flex; gap: 8px;
  max-width: 0; overflow: hidden; opacity: 0;
  transition: max-width 0.5s ease, opacity 0.4s ease;
}
.palette-dots.open {
  max-width: 200px; opacity: 1;
}
.palette-dot {
  width: 22px; height: 22px; border-radius: 50%;
  border: 2px solid transparent; cursor: pointer;
  transition: all 0.3s ease;
  flex-shrink: 0;
}
.palette-dot:hover { transform: scale(1.2); }
.palette-dot.active { border-color: var(--text); box-shadow: 0 0 0 2px var(--bg); }

/* Palette speech bubble */
.palette-speech {
  position: fixed; bottom: 80px; right: 24px;
  background: var(--card-bg); color: var(--text);
  padding: 10px 16px; border-radius: 16px 16px 4px 16px;
  font-family: 'Outfit', sans-serif; font-weight: 600; font-size: 14px;
  box-shadow: 0 4px 20px var(--card-shadow);
  opacity: 0; transform: scale(0.5);
  transition: all 0.4s cubic-bezier(0.34,1.56,0.64,1);
  pointer-events: none; z-index: 50;
}
.palette-speech.show {
  opacity: 1; transform: scale(1);
}


/* --- Floating Companion --- */
.floating-companion {
  position: fixed; bottom: 24px; right: 24px; z-index: 40;
  width: 56px; height: 56px;
  transition: all 0.5s cubic-bezier(0.22,1,0.36,1);
  opacity: 0; transform: translateY(20px);
  pointer-events: none;
}
.floating-companion.visible {
  opacity: 1; transform: translateY(0);
  pointer-events: auto;
}
.floating-companion img {
  width: 100%; height: 100%;
  filter: drop-shadow(0 4px 12px rgba(61,64,91,0.15));
  transition: transform 0.4s ease;
}
.floating-companion:hover img { transform: scale(1.1); }
.companion-dismiss {
  position: absolute; top: -6px; right: -6px;
  width: 20px; height: 20px; border-radius: 50%;
  background: var(--card-bg); border: 1px solid var(--border-subtle);
  color: var(--text-light); font-size: 11px;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer; opacity: 0;
  transition: opacity 0.3s ease;
}
.floating-companion:hover .companion-dismiss { opacity: 1; }


/* --- Responsive --- */
@media (max-width: 1024px) {
  .hero-container { flex-direction: column; text-align: center; }
  .hero-content { max-width: 100%; }
  .hero-sub { margin: 0 auto 36px; }
  .hero-cta-group { justify-content: center; }
  .hero-character img { width: 240px; }
  .hero-speech { left: auto; right: -20px; top: -10px; }
  .how-layout { flex-direction: column; align-items: center; }
  .how-text { text-align: center; padding-top: 0; }
  .chat-demo-wrapper { max-width: 100%; }
}

@media (max-width: 768px) {
  .nav { padding: 14px 20px; }
  .nav.scrolled { padding: 10px 20px; }
  .nav-links { display: none; }
  .nav-mobile-toggle { display: flex; }
  .nav-links.mobile-open {
    display: flex; flex-direction: column;
    position: absolute; top: 100%; left: 0; right: 0;
    background: var(--nav-bg);
    backdrop-filter: blur(20px);
    padding: 20px;
    box-shadow: 0 8px 30px var(--card-shadow);
    gap: 16px;
  }
  .hero { padding: 100px 20px 60px; min-height: auto; }
  .hero h1 { letter-spacing: -1px; }
  .features { padding: 80px 20px; }
  .features-grid { grid-template-columns: 1fr; gap: 16px; }
  .how-section { padding: 80px 20px; }
  .how-layout { gap: 40px; }
  .how-steps { gap: 24px; }
  .preview-section { padding: 80px 20px; }
  .personas-section { padding: 80px 20px; }
  .personas-grid { grid-template-columns: 1fr; gap: 16px; }
  .trust-row { gap: 20px; }
  .final-cta { padding: 80px 20px; }
  .final-cta-character { width: 140px; }
  .footer { padding: 32px 20px 24px; }
  .footer-top { flex-direction: column; align-items: center; text-align: center; }
  .footer-links { flex-wrap: wrap; justify-content: center; }
}

@media (max-width: 480px) {
  .hero-character img { width: 180px; }
  .btn-primary,
  .btn-secondary,
  .nav-cta { font-size: 16px; }
  .btn-primary { padding: 11px 12px 11px 24px; }
  .btn-secondary { padding: 13px 16px 13px 20px; }
  .btn-mark { width: 38px; height: 38px; }
  .chat-body { min-height: 320px; }
}