/* Sheetflow Design System */
:root {
  /* Colors */
  --color-bg: #ffffff;
  --color-fg: #0f172a;
  /* Slate 900 */
  --color-muted: #64748b;
  /* Slate 500 */
  --color-border: #e2e8f0;
  /* Slate 200 */

  --color-primary: #0f172a;
  /* Deep Navy */
  --color-primary-fg: #ffffff;

  --color-accent: #f59e0b;
  /* Amber 500 */
  --color-accent-fg: #ffffff;

  --color-surface: #f8fafc;
  /* Slate 50 */

  /* Typography */
  --font-display: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;

  /* Spacing */
  --space-4: 1rem;
  --space-8: 2rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-24: 6rem;

  /* Layout */
  --container-width: 1200px;
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
}

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

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

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

a {
  text-decoration: none;
  color: inherit;
  transition: opacity 0.2s;
}

ul {
  list-style: none;
}

/* Utilities */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

.text-center {
  text-align: center;
}

.text-muted {
  color: var(--color-muted);
}

.text-accent {
  color: var(--color-accent);
}

.text-sm {
  font-size: 0.875rem;
}

.grid {
  display: grid;
  gap: var(--space-8);
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

/* Comparison Grid */
.comparison-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-8);
  max-width: 900px;
  margin: 0 auto;
}

.comparison-list li {
  margin-bottom: 1.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--color-border);
}

.comparison-list li:last-child {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

/* Components */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 1px solid transparent;
}

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

.btn-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(15, 23, 42, 0.15);
}

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

.btn-secondary:hover {
  background: var(--color-surface);
  border-color: var(--color-muted);
}

.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.125rem;
}

.badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: 100px;
  font-size: 0.875rem;
  font-weight: 600;
  background: #eff6ff;
  color: #2563eb;
  margin-bottom: var(--space-4);
}

.card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  transition: all 0.2s ease;
}

.bg-white {
  background: white;
}

.opacity-80 {
  opacity: 0.8;
}

.card:hover {
  border-color: var(--color-muted);
}

/* Navigation */
.nav {
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(12px);
  z-index: 100;
}

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

.logo {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.5rem;
  letter-spacing: -0.04em;
}

.nav-links {
  display: flex;
  gap: var(--space-8);
  font-weight: 500;
}

/* Hero */
.hero {
  padding: var(--space-24) 0 var(--space-16);
  text-align: center;
}

.hero h1 {
  font-size: clamp(3rem, 6vw, 5rem);
  line-height: 1.1;
  margin-bottom: var(--space-8);
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--color-muted);
  max-width: 600px;
  margin: 0 auto var(--space-8);
}

.hero-cta {
  display: flex;
  gap: var(--space-4);
  justify-content: center;
}

/* Problem / Solution */
.section {
  padding: var(--space-16) 0;
}

.section-header {
  text-align: center;
  margin-bottom: var(--space-12);
}

.section-header h2 {
  font-size: 2.5rem;
  margin-bottom: var(--space-4);
}

/* How It Works */
.step-card {
  position: relative;
  border: none;
  background: var(--color-surface);
}

.step-number {
  font-family: var(--font-display);
  font-size: 4rem;
  font-weight: 800;
  color: #e2e8f0;
  line-height: 1;
  margin-bottom: var(--space-4);
}

/* Features */
.feature-icon {
  width: 48px;
  height: 48px;
  background: var(--color-surface);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-4);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}

/* Pricing */
.pricing-card {
  display: flex;
  flex-direction: column;
}

.pricing-header {
  margin-bottom: var(--space-8);
}

.price {
  font-size: 3rem;
  font-weight: 800;
  font-family: var(--font-display);
}

.price span {
  font-size: 1rem;
  color: var(--color-muted);
  font-weight: 500;
}

.features-list li {
  margin-bottom: 0.75rem;
  padding-left: 1.5rem;
  position: relative;
}

.features-list li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--color-primary);
  font-weight: bold;
}

.btn-outline {
  width: 100%;
  margin-top: auto;
  border: 1px solid var(--color-border);
  padding: 1rem;
}

.btn-outline:hover {
  background: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

/* CTA */
.cta-section {
  background: var(--color-primary);
  color: white;
  padding: var(--space-24) 0;
  text-align: center;
}

.cta-section h2 {
  font-size: 3rem;
  margin-bottom: var(--space-4);
}

.cta-section p {
  color: rgba(255, 255, 255, 0.7);
  font-size: 1.25rem;
  margin-bottom: var(--space-8);
}

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

.btn-white:hover {
  background: rgba(255, 255, 255, 0.9);
}

/* Footer */
footer {
  padding: var(--space-12) 0;
  border-top: 1px solid var(--color-border);
  text-align: center;
  color: var(--color-muted);
}

/* Mobile Responsive */
@media (max-width: 768px) {
  :root {
    --space-8: 1.5rem;
    --space-12: 2rem;
    --space-16: 3rem;
    --space-24: 4rem;
  }

  .hero h1 {
    font-size: 2.5rem;
  }

  .nav-links {
    display: none;
  }

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