:root {
  --bg-color: #1a1a1a;
  --bg-surface: #242424;
  --bg-elevated: #2d2d2d;
  --text-primary: #e3e3e3;
  --text-secondary: #a3a3a3;
  --text-muted: #737373;
  --accent-primary: #7C3AED;   /* Obsidian Purple */
  --accent-hover: #8B5CF6;
  --border-color: rgba(255, 255, 255, 0.1);
  --font-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 24px;
}

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

body {
  font-family: var(--font-base);
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  text-decoration: none;
  color: var(--text-primary);
}

.container {
  max-width: 1000px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Nav */
.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 32px 0;
}

.nav-links {
  display: flex;
  gap: 24px;
}

.nav-links a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  transition: color 0.2s ease;
}

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

.logo {
  font-weight: 600;
  font-size: 1.125rem;
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo-icon {
  width: 24px;
  height: 24px;
  background-color: var(--accent-primary);
  border-radius: 4px;
}

/* Hero */
.hero {
  padding: 80px 0 60px;
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}

.hero h1 {
  font-size: 3.5rem;
  line-height: 1.1;
  font-weight: 700;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
}

.hero p {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: 40px;
  font-weight: 400;
}

.btn-group {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 60px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  font-weight: 500;
  font-size: 1rem;
  transition: all 0.2s ease;
  cursor: pointer;
  border: 1px solid transparent;
}

.btn-primary {
  background-color: var(--accent-primary);
  color: #fff;
}

.btn-primary:hover {
  background-color: var(--accent-hover);
}

.btn-secondary {
  background-color: transparent;
  color: var(--text-primary);
  border-color: var(--border-color);
}

.btn-secondary:hover {
  background-color: rgba(255, 255, 255, 0.05);
}

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

/* Feature Split Sections */
.split-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  margin: 100px 0;
}

.split-section.reverse {
  direction: rtl;
}

.split-section.reverse > * {
  direction: ltr;
}

.split-content h2 {
  font-size: 2.5rem;
  margin-bottom: 16px;
  line-height: 1.2;
}

.split-content p {
  color: var(--text-secondary);
  font-size: 1.125rem;
  margin-bottom: 24px;
}

.split-image {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  aspect-ratio: 4/3;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
}

/* Demo Block (Like Obsidian's text demo) */
.demo-block {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 40px;
  margin-bottom: 80px;
}

.demo-block .badge {
  display: inline-block;
  padding: 4px 12px;
  background: rgba(124, 58, 237, 0.15);
  color: var(--accent-hover);
  border-radius: 100px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 16px;
}

.demo-block p {
  font-size: 1.125rem;
  color: var(--text-primary);
  line-height: 1.7;
}

.highlight {
  background-color: rgba(124, 58, 237, 0.3);
  border-bottom: 2px solid var(--accent-primary);
  padding: 0 4px;
}

/* Core Features */
.features-header {
  text-align: center;
  margin-bottom: 60px;
}

.features-header h2 {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 32px;
}

.feature-item {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  padding: 32px;
  border-radius: var(--radius-md);
}

.feature-item h3 {
  font-size: 1.25rem;
  margin-bottom: 12px;
  color: var(--accent-hover);
}

.feature-item p {
  color: var(--text-secondary);
}

.feature-item ul {
  list-style: none;
  margin-top: 16px;
  color: var(--text-secondary);
}

.feature-item ul li::before {
  content: "•";
  color: var(--text-primary);
  font-weight: bold;
  display: inline-block; 
  width: 1em;
  margin-left: -1em;
}

.feature-item ul li {
  padding-left: 1em;
  margin-bottom: 8px;
}

/* Newsletter CTA */
.cta-section {
  text-align: center;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 60px 24px;
  margin: 100px 0;
}

.cta-section h2 {
  font-size: 2rem;
  margin-bottom: 16px;
}

.cta-section p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: 32px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* Footer */
footer {
  border-top: 1px solid var(--border-color);
  padding: 60px 0 40px;
  text-align: center;
  color: var(--text-secondary);
}

.footer-nav {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-bottom: 24px;
}

@media (max-width: 768px) {
  .split-section {
    grid-template-columns: 1fr;
  }
  .hero h1 {
    font-size: 2.5rem;
  }
}