:root {
  --void: #0B0D17;
  --void-soft: #121528;
  --nebula: #7C3AED;
  --pulse: #EC4899;
  --aurora: #06B6D4;
  --star: #F8FAFC;
  --star-dim: rgba(248, 250, 252, 0.6);
  --glass: rgba(255, 255, 255, 0.06);
  --glass-border: rgba(255, 255, 255, 0.12);
  --radius: 24px;
  --transition: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Outfit', 'Noto Sans TC', sans-serif;
  background: var(--void);
  color: var(--star);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.6;
}

#starfield {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: -2;
  pointer-events: none;
}

.aurora {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(circle at 20% 30%, rgba(124, 58, 237, 0.22) 0%, transparent 45%),
    radial-gradient(circle at 80% 70%, rgba(236, 72, 153, 0.16) 0%, transparent 45%),
    radial-gradient(circle at 50% 50%, rgba(6, 182, 212, 0.10) 0%, transparent 55%);
  filter: blur(40px);
  animation: aurora-breathe 12s ease-in-out infinite alternate;
}

@keyframes aurora-breathe {
  0% { transform: scale(1) rotate(0deg); opacity: 0.8; }
  100% { transform: scale(1.15) rotate(3deg); opacity: 1; }
}

.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 2rem;
  position: relative;
}

.hero__content {
  max-width: 880px;
  animation: fade-up 1s var(--transition) both;
}

.eyebrow {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  color: var(--aurora);
  margin-bottom: 1.25rem;
  border: 1px solid var(--glass-border);
  padding: 0.5rem 1rem;
  border-radius: 999px;
  background: var(--glass);
  backdrop-filter: blur(10px);
}

.hero__title {
  font-size: clamp(4rem, 15vw, 10rem);
  font-weight: 900;
  line-height: 0.9;
  letter-spacing: -0.04em;
  margin-bottom: 1.5rem;
}

.hero__title .line {
  display: block;
}

.hero__title .line--accent {
  background: linear-gradient(135deg, var(--nebula) 0%, var(--pulse) 50%, var(--aurora) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  filter: drop-shadow(0 0 40px rgba(124, 58, 237, 0.4));
}

.hero__subtitle {
  font-size: clamp(1.1rem, 2.5vw, 1.5rem);
  font-weight: 300;
  color: var(--star-dim);
  max-width: 640px;
  margin: 0 auto 2.5rem;
}

.hero__actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.9rem 2rem;
  border-radius: 999px;
  font-weight: 700;
  text-decoration: none;
  transition: transform var(--transition), box-shadow var(--transition);
  cursor: pointer;
  border: none;
  font-size: 1rem;
}

.btn:hover {
  transform: translateY(-3px);
}

.btn--primary {
  background: linear-gradient(135deg, var(--nebula), var(--pulse));
  color: white;
  box-shadow: 0 10px 40px rgba(124, 58, 237, 0.35);
}

.btn--primary:hover {
  box-shadow: 0 14px 50px rgba(236, 72, 153, 0.45);
}

.btn--ghost {
  background: var(--glass);
  color: var(--star);
  border: 1px solid var(--glass-border);
  backdrop-filter: blur(10px);
}

.btn--ghost:hover {
  background: rgba(255, 255, 255, 0.12);
}

.hero__scroll {
  position: absolute;
  bottom: 2.5rem;
  left: 50%;
  transform: translateX(-50%);
  width: 26px;
  height: 42px;
  border: 2px solid var(--glass-border);
  border-radius: 999px;
  display: flex;
  justify-content: center;
  padding-top: 8px;
}

.hero__scroll span {
  width: 4px;
  height: 8px;
  background: var(--star);
  border-radius: 999px;
  animation: scroll-bounce 1.6s ease-in-out infinite;
}

@keyframes scroll-bounce {
  0%, 100% { transform: translateY(0); opacity: 1; }
  50% { transform: translateY(10px); opacity: 0.4; }
}

.section {
  padding: 8rem 2rem;
  position: relative;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
}

.section__title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 900;
  text-align: center;
  margin-bottom: 3rem;
  letter-spacing: -0.02em;
}

.section__desc {
  text-align: center;
  color: var(--star-dim);
  margin-top: -2rem;
  margin-bottom: 3rem;
  font-size: 1.1rem;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.card {
  background: var(--glass);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  padding: 2rem;
  backdrop-filter: blur(16px);
  transition: transform var(--transition), box-shadow var(--transition);
}

.card:hover {
  transform: translateY(-8px);
  box-shadow: 0 20px 60px rgba(124, 58, 237, 0.2);
}

.swatch {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--swatch);
  margin-bottom: 1.25rem;
  box-shadow: 0 0 30px var(--swatch);
}

.card h3 {
  font-size: 1.35rem;
  margin-bottom: 0.5rem;
}

.card p {
  color: var(--star-dim);
  font-weight: 300;
}

.draw {
  padding-bottom: 6rem;
}

#interactive-canvas {
  width: 100%;
  height: 420px;
  border-radius: var(--radius);
  background: var(--glass);
  border: 1px solid var(--glass-border);
  backdrop-filter: blur(10px);
  cursor: crosshair;
  touch-action: none;
}

.footer {
  text-align: center;
  padding: 3rem 2rem;
  color: var(--star-dim);
  font-size: 0.9rem;
  border-top: 1px solid var(--glass-border);
}

@keyframes fade-up {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 640px) {
  .hero__actions {
    flex-direction: column;
    align-items: center;
  }
  .btn {
    width: 100%;
    max-width: 280px;
  }
  .section {
    padding: 5rem 1.5rem;
  }
}