/* ===========================================
   Base Styles - Reset & Typography
   =========================================== */

/* Reset */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  overflow-x: hidden;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: var(--text-base);
  line-height: 1.7;
  color: var(--color-text-secondary);
  background-color: var(--color-bg-primary);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  padding-left: env(safe-area-inset-left);
  padding-right: env(safe-area-inset-right);
}

/* Skip to content */
.skip-link {
  position: absolute;
  top: -100%;
  left: 50%;
  transform: translateX(-50%);
  padding: 0.75rem 1.5rem;
  background: var(--color-accent-blue);
  color: white;
  border-radius: var(--radius-md);
  z-index: 9999;
  font-weight: 600;
  text-decoration: none;
}

.skip-link:focus {
  top: 1rem;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  color: var(--color-text-primary);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

h1 { font-size: var(--text-5xl); font-weight: 900; }
h2 { font-size: var(--text-3xl); font-weight: 800; }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); }

p {
  margin-bottom: 1rem;
}

p:last-child {
  margin-bottom: 0;
}

a {
  color: var(--color-accent-cyan);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-accent-blue);
}

/* Focus styles */
:focus-visible {
  outline: 2px solid var(--color-accent-blue);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* Selection */
::selection {
  background: rgba(59, 130, 246, 0.3);
  color: var(--color-text-primary);
}

/* Images */
img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* Lists */
ul, ol {
  list-style: none;
}

/* Monospace */
code, .mono {
  font-family: 'JetBrains Mono', 'Fira Code', monospace;
}

/* Utility: Gradient text */
.gradient-text {
  background: var(--gradient-hero);
  background-clip: text;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Section heading style */
.section-heading {
  text-align: center;
  margin-bottom: var(--space-3xl);
  position: relative;
}

.section-heading::after {
  content: '';
  display: block;
  width: 60px;
  height: 3px;
  margin-top: var(--space-md);
  margin-inline: auto;
  background: var(--gradient-primary);
  border-radius: 2px;
}