/* CSS Reset & Base Styles */

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--font-normal);
  line-height: var(--leading-normal);
  color: var(--text-primary);
  background-color: var(--bg-primary);
  min-height: 100vh;
  text-rendering: optimizeLegibility;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: var(--font-semibold);
  line-height: var(--leading-tight);
  color: var(--text-primary);
  letter-spacing: var(--tracking-tight);
}

h1 {
  font-size: var(--text-5xl);
  font-weight: var(--font-bold);
}

h2 {
  font-size: var(--text-4xl);
}

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

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

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

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

p {
  color: var(--text-secondary);
  line-height: var(--leading-relaxed);
}

/* Links */
a {
  color: var(--color-accent-400);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-accent-300);
}

a:focus-visible {
  outline: 2px solid var(--color-accent-500);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

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

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

/* Forms */
button, input, select, textarea {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
  color: inherit;
  background: transparent;
  border: none;
  outline: none;
}

button {
  cursor: pointer;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.5;
}

input::placeholder,
textarea::placeholder {
  color: var(--text-muted);
}

/* Tables */
table {
  border-collapse: collapse;
  width: 100%;
}

/* Code */
code, pre {
  font-family: var(--font-mono);
}

code {
  font-size: 0.875em;
  background-color: var(--bg-elevated);
  padding: 0.2em 0.4em;
  border-radius: var(--radius-sm);
}

pre {
  overflow-x: auto;
  background-color: var(--bg-elevated);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
}

pre code {
  background: none;
  padding: 0;
}

/* Selection */
::selection {
  background-color: var(--color-accent-500);
  color: var(--color-primary-950);
}

/* Scrollbar - Webkit */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
  background: var(--color-neutral-700);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-neutral-600);
}

/* Skip link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--color-accent-500);
  color: var(--color-primary-950);
  padding: var(--space-2) var(--space-4);
  z-index: var(--z-tooltip);
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 0;
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Focus visible */
:focus:not(:focus-visible) {
  outline: none;
}

/* Hidden utility */
.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;
}