/* ============================================
   BASE STYLES — Reset, Fonts, Globals
   ============================================
   Rule 17: Accessibility — contrast, focus, hierarchy
   Rule 6: Typography — max 70 chars per line
   ============================================ */

/* ---- Font Imports ---- */
@import url('https://fonts.googleapis.com/css2?family=Instrument+Serif:ital@0;1&family=Inter:wght@400;500;600&display=swap');

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

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

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

/* ---- Selection ---- */
::selection {
  background: var(--color-selection);
  color: var(--color-text-primary);
}

/* ---- Scrollbar ---- */
::-webkit-scrollbar {
  width: 6px;
}

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

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

::-webkit-scrollbar-thumb:hover {
  background: var(--color-text-secondary);
}

/* ---- Accessibility: Skip Link ---- */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  padding: var(--space-3) var(--space-6);
  background: var(--color-accent);
  color: #fff;
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  border-radius: var(--radius-md);
  z-index: 9999;
  transition: top var(--duration-fast) var(--ease-out);
}

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

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

/* Remove outline for mouse users */
:focus:not(:focus-visible) {
  outline: none;
}

/* ---- Base Elements ---- */
h1, h2, h3, h4, h5, h6 {
  font-weight: var(--weight-regular);
  line-height: var(--leading-tight);
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--duration-fast) var(--ease-out);
}

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

ul, ol {
  list-style: none;
}

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

button {
  border: none;
  background: none;
  cursor: pointer;
  font-family: inherit;
  font-size: inherit;
  color: inherit;
}

input, textarea {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
  background: none;
  border: none;
  outline: none;
}

/* ---- Typography: Line Length (Rule 6) ---- */
p, .text-readable {
  max-width: 65ch;
}

/* ---- Utilities ---- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-6);
}

.container--narrow {
  max-width: var(--max-width-narrow);
}

.container--wide {
  max-width: var(--max-width-wide);
}

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

/* ---- Section Spacing ---- */
section {
  padding: var(--section-padding) 0;
  position: relative;
}

/* ---- Dot Grid Background (subtle) ---- */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: radial-gradient(circle, var(--color-text-tertiary) 0.5px, transparent 0.5px);
  background-size: 32px 32px;
  opacity: 0.12;
  pointer-events: none;
  z-index: 0;
}

body > * {
  position: relative;
  z-index: var(--z-base);
}