:root {
  --bg: #0a0a0f;
  --bg-elevated: #12121a;
  --bg-card: #16161f;
  --fg: #e8e8ed;
  --fg-muted: #8888a0;
  --fg-dim: #55556a;
  --accent: #00e599;
  --accent-glow: rgba(0, 229, 153, 0.15);
  --accent-dim: #00b377;
  --waveform: #6c5ce7;
  --waveform-glow: rgba(108, 92, 231, 0.2);
  --signal: #ff6b6b;
  --border: rgba(255,255,255,0.06);
  --mono: 'JetBrains Mono', monospace;
  --sans: 'Space Grotesk', sans-serif;
  --radius: 16px;
  --radius-sm: 10px;
}

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

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

.hero::before {
  content: '';
  position: absolute;
  top: -200px;
  left: 50%;
  transform: translateX(-50%);
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -100px;
  right: -200px;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--waveform-glow) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

.hero-content { position: relative; z-index: 1; max-width: 820px; }

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 100px;
  font-family: var(--mono);
  font-size: 0.8rem;
  color: var(--accent);
  letter-spacing: 0.05em;
  margin-bottom: 2rem;
}

.hero-tag .dot {
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.8); }
}

.hero h1 {
  font-size: clamp(2.8rem, 7vw, 5.5rem);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
}

.hero h1 .highlight {
  background: linear-gradient(135deg, var(--accent) 0%, #00d4aa 50%, var(--waveform) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-sub {
  font-size: clamp(1.05rem, 2vw, 1.3rem);
  color: var(--fg-muted);
  max-width: 560px;
  margin: 0 auto 2.5rem;
  line-height: 1.7;
}

.hero-demo {
  display: flex;
  flex-direction: column;
  gap: 12px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  max-width: 480px;
  margin: 0 auto;
  text-align: left;
  font-family: var(--mono);
  font-size: 0.85rem;
}

.demo-line {
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

.demo-label {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 2px 8px;
  border-radius: 4px;
  white-space: nowrap;
  font-weight: 500;
  min-width: 48px;
  text-align: center;
}

.demo-label.ai {
  background: var(--accent-glow);
  color: var(--accent);
  border: 1px solid rgba(0, 229, 153, 0.2);
}

.demo-label.caller {
  background: var(--waveform-glow);
  color: #a29bfe;
  border: 1px solid rgba(108, 92, 231, 0.2);
}

.demo-label.you {
  background: rgba(255, 107, 107, 0.1);
  color: var(--signal);
  border: 1px solid rgba(255, 107, 107, 0.2);
}

.demo-text { color: var(--fg-muted); line-height: 1.5; }

.demo-divider {
  border: none;
  border-top: 1px dashed var(--border);
  margin: 4px 0;
}

.demo-action {
  color: var(--fg-dim);
  font-style: italic;
  font-size: 0.78rem;
  padding-left: 58px;
}

/* ===== HOW ===== */
.how {
  padding: 6rem 2rem;
  max-width: 1100px;
  margin: 0 auto;
}

.how h2 {
  font-size: clamp(1.4rem, 3vw, 1.8rem);
  font-weight: 600;
  margin-bottom: 3rem;
  color: var(--fg);
  text-align: center;
}

.how-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2px;
  background: var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.how-step {
  background: var(--bg-elevated);
  padding: 2.5rem 2rem;
  position: relative;
}

.step-num {
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--accent);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 1rem;
}

.how-step h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
}

.how-step p {
  color: var(--fg-muted);
  font-size: 0.92rem;
  line-height: 1.6;
}

/* ===== FEATURES ===== */
.features {
  padding: 6rem 2rem;
  max-width: 1100px;
  margin: 0 auto;
}

.features h2 {
  font-size: clamp(1.4rem, 3vw, 1.8rem);
  font-weight: 600;
  margin-bottom: 1rem;
  text-align: center;
}

.features-sub {
  text-align: center;
  color: var(--fg-muted);
  margin-bottom: 3rem;
  font-size: 1.05rem;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 2rem;
  transition: border-color 0.3s ease;
}

.feature-card:hover {
  border-color: rgba(0, 229, 153, 0.2);
}

.feature-icon {
  font-size: 1.6rem;
  margin-bottom: 1rem;
  display: block;
}

.feature-card h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.feature-card p {
  color: var(--fg-muted);
  font-size: 0.9rem;
  line-height: 1.6;
}

/* ===== SPECS ===== */
.specs {
  padding: 5rem 2rem;
  max-width: 900px;
  margin: 0 auto;
}

.specs h2 {
  font-size: clamp(1.4rem, 3vw, 1.8rem);
  font-weight: 600;
  margin-bottom: 2.5rem;
  text-align: center;
}

.spec-row {
  display: flex;
  justify-content: space-between;
  padding: 1.2rem 0;
  border-bottom: 1px solid var(--border);
}

.spec-row:last-child { border-bottom: none; }

.spec-key {
  color: var(--fg-muted);
  font-size: 0.92rem;
}

.spec-val {
  font-weight: 500;
  font-size: 0.92rem;
  text-align: right;
  color: var(--fg);
}

.spec-val .accent { color: var(--accent); }

/* ===== CLOSING ===== */
.closing {
  padding: 8rem 2rem;
  text-align: center;
  position: relative;
}

.closing::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 600px;
  height: 400px;
  background: radial-gradient(circle, var(--waveform-glow) 0%, transparent 70%);
  pointer-events: none;
}

.closing-content { position: relative; z-index: 1; max-width: 640px; margin: 0 auto; }

.closing h2 {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 1.5rem;
}

.closing p {
  color: var(--fg-muted);
  font-size: 1.1rem;
  line-height: 1.7;
}

/* ===== FOOTER ===== */
footer {
  padding: 3rem 2rem;
  text-align: center;
  border-top: 1px solid var(--border);
}

footer p {
  color: var(--fg-dim);
  font-size: 0.82rem;
  font-family: var(--mono);
}

/* ===== MOBILE ===== */
@media (max-width: 768px) {
  .how-grid { grid-template-columns: 1fr; }
  .feature-grid { grid-template-columns: 1fr; }
  .spec-row { flex-direction: column; gap: 4px; }
  .spec-val { text-align: left; }
  .hero-demo { margin: 0 1rem; }
}

@media (max-width: 480px) {
  .hero { padding: 1.5rem; min-height: 90vh; }
  .hero-demo { padding: 16px; }
  .how-step { padding: 1.5rem; }
  .feature-card { padding: 1.5rem; }
}