/* ============================================================
   BASE — reset, typography, utilities
   ============================================================ */

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

html {
  -webkit-text-size-adjust: 100%;
  -moz-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  tab-size: 4;
}

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

body {
  margin: 0;
  font-family: var(--font-family-base);
  font-size: var(--fs-body);
  font-weight: var(--fw-regular);
  line-height: var(--lh-normal);
  color: var(--text-primary);
  background-color: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  transition: background-color var(--dur-base) var(--ease-in-out),
              color var(--dur-base) var(--ease-in-out);
  min-height: 100vh;
  min-height: 100dvh;
}

h1, h2, h3, h4, h5, h6, p, ul, ol, figure, blockquote, dl, dd {
  margin: 0;
}

ul, ol {
  padding: 0;
  list-style: none;
}

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

img {
  height: auto;
  border-radius: var(--radius-sm);
}

a {
  color: inherit;
  text-decoration: none;
}

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

button {
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

input, textarea, select {
  background-color: var(--card);
  border: var(--border-w) solid var(--border);
  color: var(--text-primary);
}

textarea { resize: vertical; }

:focus { outline: none; }
:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: var(--radius-xs);
}

::selection {
  background: var(--blue);
  color: #fff;
}

/* ============================================================
   TYPOGRAPHY
   ============================================================ */

h1, .h1 {
  font-size: var(--fs-h1);
  font-weight: var(--fw-bold);
  line-height: var(--lh-tight);
  letter-spacing: -0.01em;
  color: var(--text-primary);
}

h2, .h2 {
  font-size: var(--fs-h2);
  font-weight: var(--fw-bold);
  line-height: var(--lh-snug);
  letter-spacing: -0.005em;
  color: var(--text-primary);
}

h3, .h3 {
  font-size: var(--fs-h3);
  font-weight: var(--fw-semibold);
  line-height: var(--lh-snug);
  color: var(--text-primary);
}

h4, .h4 {
  font-size: var(--fs-h4);
  font-weight: var(--fw-semibold);
  line-height: var(--lh-snug);
  color: var(--text-primary);
}

.display {
  font-size: var(--fs-display);
  font-weight: var(--fw-extra);
  line-height: var(--lh-tight);
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

p {
  color: var(--text-primary);
  line-height: var(--lh-relaxed);
}

.lead {
  font-size: 1.125rem;
  color: var(--text-secondary);
  line-height: var(--lh-relaxed);
  max-width: 60ch;
}

.muted { color: var(--text-secondary); }
.dim   { color: var(--text-tertiary); }

.label {
  display: inline-block;
  font-size: var(--fs-label);
  font-weight: var(--fw-bold);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-tertiary);
  margin-bottom: var(--sp-3);
}

.section-title {
  font-size: var(--fs-h1);
  font-weight: var(--fw-bold);
  line-height: var(--lh-tight);
  letter-spacing: -0.01em;
  margin-bottom: var(--sp-4);
}

.section-subtitle {
  font-size: 1.125rem;
  color: var(--text-secondary);
  line-height: var(--lh-relaxed);
  max-width: 56ch;
  margin: 0 auto;
}

/* ============================================================
   LAYOUT UTILITIES
   ============================================================ */

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--sp-5);
}

@media (min-width: 768px) {
  .container { padding-inline: var(--sp-8); }
}

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

.section {
  padding-block: var(--sp-16);
}
@media (min-width: 768px) {
  .section { padding-block: var(--sp-20); }
}

.section--sm { padding-block: var(--sp-12); }
.section--xl { padding-block: var(--sp-24); }

.section-head {
  text-align: center;
  margin-bottom: var(--sp-12);
}
.section-head .label { margin-bottom: var(--sp-3); }

.grid {
  display: grid;
  gap: var(--sp-6);
}
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 1023px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 639px) {
  .grid-4, .grid-3, .grid-2 { grid-template-columns: 1fr; }
}

.stack       { display: flex; flex-direction: column; gap: var(--sp-4); }
.stack-sm    { display: flex; flex-direction: column; gap: var(--sp-2); }
.stack-lg    { display: flex; flex-direction: column; gap: var(--sp-8); }
.row         { display: flex; align-items: center; gap: var(--sp-3); flex-wrap: wrap; }
.row-tight   { display: flex; align-items: center; gap: var(--sp-2); flex-wrap: wrap; }
.center      { display: flex; align-items: center; justify-content: center; }
.between     { display: flex; align-items: center; justify-content: space-between; gap: var(--sp-4); }

.text-center { text-align: center; }
.text-left   { text-align: left; }

.divider {
  height: 1px;
  background-color: var(--border);
  width: 100%;
}

/* Skip link for keyboard users */
.skip-link {
  position: absolute;
  top: -100px;
  left: var(--sp-4);
  padding: var(--sp-3) var(--sp-4);
  background: var(--blue);
  color: #fff;
  border-radius: var(--radius-sm);
  z-index: var(--z-toast);
  transition: top var(--dur-base) var(--ease-out);
}
.skip-link:focus { top: var(--sp-4); }

/* Visually hidden but accessible to AT */
.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;
}

/* Spacing utilities */
.mt-0  { margin-top: 0 !important; }
.mt-2  { margin-top: var(--sp-2); }
.mt-3  { margin-top: var(--sp-3); }
.mt-4  { margin-top: var(--sp-4); }
.mt-6  { margin-top: var(--sp-6); }
.mt-8  { margin-top: var(--sp-8); }
.mt-12 { margin-top: var(--sp-12); }
.mb-2  { margin-bottom: var(--sp-2); }
.mb-3  { margin-bottom: var(--sp-3); }
.mb-4  { margin-bottom: var(--sp-4); }
.mb-6  { margin-bottom: var(--sp-6); }
.mb-8  { margin-bottom: var(--sp-8); }

/* No-scroll lock used by mobile drawer */
body.no-scroll { overflow: hidden; }