/* Base Styles - Reset, Typography, and Foundational Elements */

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-regular);
  line-height: var(--line-height-normal);
  color: var(--color-text);
  background-color: var(--color-background);
  overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  color: var(--color-primary);
  margin-bottom: var(--spacing-md);
}

h1 {
  font-size: var(--font-size-4xl);
}

h2 {
  font-size: var(--font-size-3xl);
}

h3 {
  font-size: var(--font-size-2xl);
}

h4 {
  font-size: var(--font-size-xl);
}

h5 {
  font-size: var(--font-size-lg);
}

h6 {
  font-size: var(--font-size-base);
}

p {
  margin-bottom: var(--spacing-md);
}

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

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

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

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

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

/* Buttons */
button {
  font-family: inherit;
  font-size: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

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

/* Form Elements */
input,
textarea,
select {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
}

/* Utility Classes */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Skip to content link for accessibility */
.skip-to-content {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-primary);
  color: var(--color-background);
  padding: var(--spacing-sm) var(--spacing-md);
  text-decoration: none;
  z-index: var(--z-tooltip);
}

.skip-to-content:focus {
  top: 0;
}

/* Responsive Typography */
@media (max-width: 768px) {
  :root {
    --font-size-4xl: 39px;
    --font-size-3xl: 31px;
    --font-size-2xl: 25px;
  }
}

@media (max-width: 480px) {
  :root {
    --font-size-4xl: 31px;
    --font-size-3xl: 25px;
    --font-size-2xl: 20px;
  }
}