/**
 * Base styles — reset, typography, accessibility
 */

*,
*::before,
*::after {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

img,
picture,
video,
canvas,
svg {
  display: block;
  max-width: 100%;
  height: auto;
}

input,
button,
textarea,
select {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
}

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

a:hover {
  color: var(--color-primary-dark);
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* Skip link for accessibility */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  padding: var(--space-2) var(--space-4);
  background: var(--color-primary);
  color: white;
  font-weight: var(--font-semibold);
  z-index: 9999;
  border-radius: var(--radius-md);
  transition: top var(--transition-base);
}

.skip-link:focus {
  top: var(--space-4);
}

/* Headings — semantic hierarchy */
h1, h2, h3, h4, h5, h6 {
  margin: 0 0 var(--space-4);
  font-family: var(--font-display);
  font-weight: var(--font-bold);
  line-height: var(--leading-tight);
  color: var(--color-text);
}

h1 { font-size: clamp(var(--text-3xl), 5vw, var(--text-5xl)); }
h2 { font-size: clamp(var(--text-2xl), 4vw, var(--text-4xl)); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }
h5, h6 { font-size: var(--text-base); }

p {
  margin: 0 0 var(--space-4);
  color: var(--color-text-muted);
}

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

/* Ensure sufficient contrast (WCAG) */
/* Utility: visually hidden but available to screen readers */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

@media (prefers-contrast: high) {
  :root {
    --color-text-muted: #2d3d45;
    --color-border: #b0bcc2;
  }
}