:root {
  --bg: #ffffff;
  --text: #000000;
  --text-muted: #666666;
  --border: #000000;
}

[data-theme="dark"] {
  --bg: #000000;
  --text: #ffffff;
  --text-muted: #999999;
  --border: #ffffff;
}

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

html {
  font-size: 16px;
}

body {
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  min-height: 100vh;
}

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 80px 40px;
}

/* Controls */
.controls {
  position: fixed;
  top: 24px;
  right: 24px;
  display: flex;
  gap: 8px;
  z-index: 100;
}

.ctrl-btn {
  width: 32px;
  height: 32px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
  font-size: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s;
}

.ctrl-btn:hover {
  background: var(--text);
  color: var(--bg);
}

.ctrl-btn svg {
  width: 16px;
  height: 16px;
}

/* Hero */
.hero {
  text-align: center;
  margin-bottom: 100px;
}

.hero h1 {
  font-size: 48px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 48px;
}

/* Flow Diagram */
.flow {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  margin-bottom: 32px;
}

.flow-box {
  width: 80px;
  height: 80px;
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.flow-box.logo {
  border: none;
  width: 100px;
  height: 100px;
}

.flow-box.logo img {
  width: 100%;
  height: 100%;
}

.flow-arrow {
  font-size: 24px;
  color: var(--text-muted);
}

/* Hero Text */
.hero-text .tagline {
  font-size: 18px;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.hero-text .subtitle {
  font-size: 14px;
  color: var(--text-muted);
}

/* Divider */
.divider {
  height: 1px;
  background: var(--border);
  margin: 60px 0;
}

/* Section Title */
.section-title {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 14px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 48px;
}

.section-title::before {
  content: '';
  width: 12px;
  height: 12px;
  background: var(--text);
}

/* Features */
.features {
  margin-bottom: 60px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 48px;
}

.feature h3 {
  font-size: 14px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 8px;
}

.feature p {
  font-size: 14px;
  color: var(--text-muted);
}

/* Install */
.install-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.install-step {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 12px;
}

.install-number {
  width: 24px;
  height: 24px;
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 700;
}

.install-text {
  font-size: 14px;
}

.install-text a {
  color: var(--text);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.install-text a:hover {
  opacity: 0.7;
}

/* Footer */
.footer {
  text-align: center;
  padding: 60px 0 40px;
  font-size: 12px;
  color: var(--text-muted);
}

/* Responsive */
@media (max-width: 768px) {
  .container {
    padding: 40px 24px;
  }
  
  .hero {
    margin-bottom: 60px;
  }
  
  .hero h1 {
    font-size: 36px;
    margin-bottom: 32px;
  }
  
  .flow {
    flex-direction: column;
    gap: 16px;
    margin-bottom: 24px;
  }
  
  .flow-arrow {
    transform: rotate(90deg);
  }
  
  .flow-box.logo {
    width: 80px;
    height: 80px;
  }
  
  .features-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  
  .divider {
    margin: 48px 0;
  }
  
  .install-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
}