/* ===========================================
   Kairos AI — Corporate Website
   Style: Warm, Friendly, Professional
   =========================================== */

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

:root {
  /* Brand Colors — warm amber palette */
  --amber-50: #FFFBEB;
  --amber-100: #FEF3C7;
  --amber-200: #FDE68A;
  --amber-300: #FCD34D;
  --amber-400: #FBBF24;
  --amber-500: #F59E0B;
  --amber-600: #D97706;
  --amber-700: #B45309;

  /* Neutrals */
  --gray-50: #F9FAFB;
  --gray-100: #F3F4F6;
  --gray-200: #E5E7EB;
  --gray-300: #D1D5DB;
  --gray-400: #9CA3AF;
  --gray-500: #6B7280;
  --gray-600: #4B5563;
  --gray-700: #374151;
  --gray-800: #1F2937;
  --gray-900: #111827;

  /* Semantic */
  --text-primary: var(--gray-800);
  --text-secondary: var(--gray-600);
  --text-muted: var(--gray-400);
  --bg-primary: #FFFFFF;
  --bg-secondary: var(--gray-50);
  --brand: var(--amber-500);
  --brand-dark: var(--amber-600);
  --brand-light: var(--amber-100);

  /* Typography */
  --font: 'Noto Sans TC', -apple-system, BlinkMacSystemFont, sans-serif;

  /* Spacing */
  --section-py: 120px;

  /* Transitions */
  --ease: cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font);
  color: var(--text-primary);
  background: var(--bg-primary);
  line-height: 1.7;
  overflow-x: hidden;
}

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

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

/* --- Container --- */
.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

/* --- Navigation --- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 16px 0;
  transition: all 0.4s var(--ease);
}

.nav.scrolled {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 1px 20px rgba(0, 0, 0, 0.06);
  padding: 10px 0;
}

.nav-inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav-logo-icon {
  width: 38px;
  height: 38px;
  background: linear-gradient(135deg, var(--amber-400), var(--amber-600));
  color: white;
  font-weight: 900;
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
}

.nav-logo-text {
  font-weight: 700;
  font-size: 18px;
  color: var(--text-primary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 36px;
}

.nav-link {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.3s var(--ease);
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--brand);
  transition: width 0.3s var(--ease);
  border-radius: 1px;
}

.nav-link:hover {
  color: var(--text-primary);
}

.nav-link:hover::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all 0.3s var(--ease);
}

/* --- Hero --- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  padding: 120px 24px 80px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
}

.hero-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.4;
  animation: orbFloat 20s ease-in-out infinite;
}

.hero-orb-1 {
  width: 600px;
  height: 600px;
  background: var(--amber-200);
  top: -10%;
  right: -10%;
  animation-delay: 0s;
}

.hero-orb-2 {
  width: 400px;
  height: 400px;
  background: var(--amber-100);
  bottom: -5%;
  left: -5%;
  animation-delay: -7s;
}

.hero-orb-3 {
  width: 300px;
  height: 300px;
  background: #FDE68A;
  top: 40%;
  left: 30%;
  animation-delay: -14s;
}

@keyframes orbFloat {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(30px, -30px) scale(1.05); }
  66% { transform: translate(-20px, 20px) scale(0.95); }
}

.hero-content {
  position: relative;
  text-align: center;
  max-width: 720px;
  animation: heroFadeIn 1s var(--ease) forwards;
  opacity: 0;
  transform: translateY(30px);
}

@keyframes heroFadeIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 18px;
  background: var(--amber-50);
  border: 1px solid var(--amber-200);
  border-radius: 100px;
  font-size: 14px;
  font-weight: 500;
  color: var(--amber-700);
  margin-bottom: 28px;
}

.hero-badge-dot {
  width: 8px;
  height: 8px;
  background: var(--amber-500);
  border-radius: 50%;
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

.hero-title {
  font-size: clamp(36px, 6vw, 60px);
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin-bottom: 24px;
}

.hero-highlight {
  background: linear-gradient(135deg, var(--amber-400), var(--amber-600));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(16px, 2vw, 19px);
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: 40px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 600;
  font-family: var(--font);
  cursor: pointer;
  transition: all 0.3s var(--ease);
  border: none;
}

.btn-primary {
  background: linear-gradient(135deg, var(--amber-400), var(--amber-500));
  color: white;
  box-shadow: 0 4px 20px rgba(245, 158, 11, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(245, 158, 11, 0.4);
}

.btn-outline {
  background: transparent;
  color: var(--text-secondary);
  border: 1.5px solid var(--gray-200);
}

.btn-outline:hover {
  border-color: var(--amber-300);
  color: var(--amber-700);
  background: var(--amber-50);
}

/* --- Hero Scroll Hint --- */
.hero-scroll-hint {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  opacity: 0.5;
  animation: scrollHint 2s ease-in-out infinite;
}

.hero-scroll-hint span {
  font-size: 13px;
  color: var(--text-muted);
  font-weight: 500;
}

.hero-scroll-arrow {
  width: 20px;
  height: 20px;
  border-right: 2px solid var(--text-muted);
  border-bottom: 2px solid var(--text-muted);
  transform: rotate(45deg);
}

@keyframes scrollHint {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(8px); }
}

/* --- Sections --- */
.section {
  padding: var(--section-py) 0;
}

.section-header {
  text-align: center;
  margin-bottom: 64px;
}

.section-tag {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.15em;
  color: var(--amber-600);
  margin-bottom: 12px;
}

.section-title {
  font-size: clamp(28px, 4vw, 42px);
  font-weight: 800;
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}

.section-desc {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto;
}

/* --- About Section --- */
.about {
  background: var(--bg-secondary);
}

.about-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.about-card {
  background: white;
  border-radius: 20px;
  padding: 40px 32px;
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.04);
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.about-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.08);
}

.about-card-icon {
  width: 52px;
  height: 52px;
  background: var(--amber-50);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--amber-600);
}

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

.about-card-title {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 12px;
}

.about-card-text {
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-secondary);
}

/* --- Product Section --- */
.product-hero {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
}

.product-hero-visual {
  display: flex;
  justify-content: center;
}

/* Phone Mockup */
.phone-mockup {
  width: 280px;
  background: var(--gray-900);
  border-radius: 36px;
  padding: 12px;
  box-shadow:
    0 30px 80px rgba(0, 0, 0, 0.15),
    0 0 0 1px rgba(255, 255, 255, 0.1) inset;
}

.phone-screen {
  background: white;
  border-radius: 26px;
  overflow: hidden;
  aspect-ratio: 9 / 16.5;
  display: flex;
  flex-direction: column;
}

.phone-status-bar {
  display: flex;
  justify-content: space-between;
  padding: 12px 20px 8px;
  font-size: 12px;
  font-weight: 600;
  color: var(--gray-700);
}

.phone-app {
  flex: 1;
  padding: 16px 20px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.phone-greeting {
  font-size: 20px;
  font-weight: 700;
  color: var(--gray-800);
}

.phone-chips {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.phone-chip {
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
  background: var(--gray-100);
  color: var(--gray-600);
}

.phone-chip.active {
  background: var(--amber-500);
  color: white;
}

.phone-card {
  background: white;
  border: 1.5px solid var(--gray-200);
  border-radius: 16px;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
}

.phone-card-rating {
  font-size: 13px;
  font-weight: 600;
  color: var(--amber-600);
}

.phone-card-name {
  font-size: 18px;
  font-weight: 700;
}

.phone-card-desc {
  font-size: 12px;
  line-height: 1.6;
  color: var(--gray-500);
}

.phone-card-info {
  display: flex;
  gap: 12px;
  font-size: 12px;
  color: var(--gray-500);
  margin-top: auto;
}

.phone-btn {
  background: linear-gradient(135deg, var(--amber-400), var(--amber-500));
  color: white;
  text-align: center;
  padding: 14px;
  border-radius: 14px;
  font-size: 15px;
  font-weight: 700;
}

/* Product Text */
.product-hero-title {
  font-size: clamp(28px, 3.5vw, 38px);
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 20px;
}

.text-amber {
  color: var(--amber-600);
}

.product-hero-desc {
  font-size: 17px;
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: 36px;
}

.product-stats {
  display: flex;
  gap: 40px;
}

.product-stat {
  display: flex;
  flex-direction: column;
}

.product-stat-num {
  font-size: 36px;
  font-weight: 900;
  color: var(--amber-500);
  line-height: 1;
}

.product-stat-label {
  font-size: 14px;
  color: var(--text-muted);
  margin-top: 4px;
}

/* --- Features --- */
.features {
  background: var(--bg-secondary);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: white;
  border-radius: 20px;
  padding: 36px 28px;
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease);
  box-shadow: 0 2px 16px rgba(0, 0, 0, 0.03);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.08);
}

.feature-icon {
  width: 56px;
  height: 56px;
  background: var(--amber-50);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--amber-600);
}

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

.feature-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 10px;
}

.feature-desc {
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-secondary);
}

/* --- CTA Section --- */
.cta {
  padding: 80px 0;
}

.cta-card {
  background: linear-gradient(135deg, var(--amber-50) 0%, var(--amber-100) 100%);
  border-radius: 28px;
  padding: 72px 48px;
  text-align: center;
  border: 1px solid var(--amber-200);
}

.cta-title {
  font-size: clamp(24px, 3vw, 32px);
  font-weight: 800;
  margin-bottom: 16px;
}

.cta-desc {
  font-size: 18px;
  color: var(--text-secondary);
  margin-bottom: 36px;
}

.cta-badges {
  display: flex;
  gap: 20px;
  justify-content: center;
  flex-wrap: wrap;
}

.store-badge {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 28px;
  background: white;
  border-radius: 14px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  transition: transform 0.3s var(--ease);
}

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

.store-badge svg {
  flex-shrink: 0;
}

.store-badge-sub {
  display: block;
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 500;
}

.store-badge-main {
  display: block;
  font-size: 16px;
  font-weight: 700;
}

/* --- Contact Section --- */
.contact-info {
  display: flex;
  gap: 32px;
  justify-content: center;
  flex-wrap: wrap;
}

.contact-card {
  background: white;
  border-radius: 20px;
  padding: 40px 48px;
  text-align: center;
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.04);
  min-width: 280px;
}

.contact-icon {
  margin-bottom: 16px;
  color: var(--amber-600);
  display: flex;
  justify-content: center;
}

.contact-label {
  font-size: 14px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 8px;
}

.contact-value {
  font-size: 17px;
  font-weight: 600;
  color: var(--text-primary);
}

.contact-value-en {
  font-size: 14px;
  color: var(--text-muted);
  margin-top: 4px;
}

a.contact-value {
  color: var(--amber-600);
  transition: color 0.3s;
}

a.contact-value:hover {
  color: var(--amber-700);
}

/* --- Footer --- */
.footer {
  padding: 40px 0;
  border-top: 1px solid var(--gray-100);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.footer-brand-text {
  font-weight: 700;
  font-size: 16px;
}

.footer-copy {
  font-size: 13px;
  color: var(--text-muted);
}

/* --- Reveal Animation --- */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* --- Responsive --- */
@media (max-width: 900px) {
  :root {
    --section-py: 80px;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .product-hero {
    grid-template-columns: 1fr;
    gap: 48px;
    text-align: center;
  }

  .product-hero-visual {
    order: -1;
  }

  .product-stats {
    justify-content: center;
  }

  .features-grid {
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }

  .footer-inner {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }
}

@media (max-width: 640px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: white;
    flex-direction: column;
    padding: 20px 24px;
    gap: 16px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    border-radius: 0 0 16px 16px;
  }

  .nav-links.open {
    display: flex;
  }

  .nav-toggle {
    display: flex;
  }

  .hero {
    padding: 100px 24px 60px;
    min-height: auto;
  }

  .hero-title {
    font-size: 32px;
  }

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

  .cta-card {
    padding: 48px 24px;
  }

  .contact-info {
    flex-direction: column;
    align-items: center;
  }

  .phone-mockup {
    width: 240px;
  }
}