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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-system);
  font-size: 16px;
  line-height: 1.6;
  color: var(--ink-700);
  background: linear-gradient(180deg, var(--bg-gradient-start) 0%, var(--bg-gradient-mid) 50%, var(--bg-gradient-end) 100%);
  background-attachment: fixed;
  min-height: 100vh;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.container-narrow {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

h1, h2, h3, h4 {
  color: var(--ink-900);
  font-weight: 700;
  line-height: 1.2;
}

h1 {
  font-size: clamp(32px, 5vw, 48px);
  font-weight: 800;
  margin-bottom: var(--spacing-md);
}

h2 {
  font-size: clamp(24px, 4vw, 32px);
  margin-bottom: var(--spacing-sm);
}

h3 {
  font-size: 20px;
  margin-bottom: var(--spacing-xs);
}

p {
  margin-bottom: var(--spacing-sm);
  max-width: 65ch;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: opacity 0.2s;
}

a:hover {
  text-decoration: underline;
  opacity: 0.8;
}

a:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
  border-radius: 2px;
}

.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: var(--spacing-sm) 0;
  transition: box-shadow 0.3s;
}

.nav.scrolled {
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.nav-logo {
  font-size: 20px;
  font-weight: 700;
  color: var(--ink-900);
  text-decoration: none;
}

.nav-logo:hover {
  text-decoration: none;
  opacity: 1;
}

.nav-menu {
  display: flex;
  gap: var(--spacing-lg);
  align-items: center;
  list-style: none;
}

.nav-link {
  color: var(--ink-700);
  font-weight: 500;
  text-decoration: none;
  transition: color 0.2s;
}

.nav-link:hover {
  color: var(--primary);
  text-decoration: none;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 24px;
  cursor: pointer;
  color: var(--ink-900);
  padding: 8px;
}

@media (max-width: 768px) {
  .nav-toggle {
    display: block;
  }
  
  .nav-menu {
    position: fixed;
    top: 65px;
    right: -100%;
    width: 100%;
    max-width: 300px;
    background: white;
    flex-direction: column;
    align-items: flex-start;
    padding: var(--spacing-md);
    box-shadow: -4px 0 12px rgba(0, 0, 0, 0.1);
    transition: right 0.3s;
    height: calc(100vh - 65px);
  }
  
  .nav-menu.active {
    right: 0;
  }
  
  .nav-menu li {
    width: 100%;
    padding: var(--spacing-xs) 0;
  }
}

.footer {
  margin-top: var(--spacing-3xl);
  padding: var(--spacing-lg) 0;
  border-top: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.6);
}

.footer-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  flex-wrap: wrap;
  gap: var(--spacing-md);
}

.footer-left {
  color: var(--ink-500);
  font-size: 14px;
}

.footer-links {
  display: flex;
  gap: var(--spacing-md);
  list-style: none;
}

.footer-link {
  color: var(--ink-500);
  font-size: 14px;
  text-decoration: none;
}

.footer-link:hover {
  color: var(--primary);
}

@media (max-width: 640px) {
  .footer-container {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }
}