/* ==========================================================================
   21st Template Systems — core.css
   Base + components. Every value comes from tokens (ds/themes.css).
   Class names mirror shadcn/ui component names so markup ports to React 1:1.
   ========================================================================== */

/* ---------- 1. Base ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--background);
  color: var(--foreground);
  font-family: var(--font-sans);
  font-size: var(--text-body);
  line-height: 1.6;
  word-break: keep-all;
  overflow-wrap: anywhere;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img, svg, video { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button, input, select, textarea { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--ring); outline-offset: 2px; }
::selection { background: color-mix(in srgb, var(--primary) 22%, transparent); }
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 1ms !important; transition-duration: 1ms !important; scroll-behavior: auto !important; }
}

/* ---------- 2. Typography ---------- */
.display-2xl, .display-xl, .h1, .h2 {
  font-family: var(--font-display);
  font-weight: var(--display-weight);
  letter-spacing: var(--display-tracking);
  line-height: var(--display-leading);
  margin: 0;
  text-wrap: balance;
}
.display-2xl { font-size: var(--text-display-2xl); }
.display-xl { font-size: var(--text-display-xl); }
.h1 { font-size: var(--text-h1); }
.h2 { font-size: var(--text-h2); line-height: calc(var(--display-leading) + 0.06); }
.h3 { font-size: var(--text-h3); font-weight: 600; letter-spacing: -0.015em; line-height: 1.35; margin: 0; }
.lead { font-size: var(--text-lead); color: var(--muted-foreground); line-height: 1.6; margin: 0; text-wrap: pretty; }
.small { font-size: var(--text-small); }
.xs { font-size: var(--text-xs); }
.muted { color: var(--muted-foreground); }
.mono { font-family: var(--font-mono); font-size: 0.8125em; letter-spacing: 0; }
.tabular { font-variant-numeric: tabular-nums; }
.kicker { font-family: var(--font-mono); font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted-foreground); }
/* accent word: Instrument Serif italic (cobalt/folio), serif italic (serif) … */
.em { font-synthesis: none; font-family: var(--font-accent); font-style: var(--accent-style); font-weight: var(--accent-weight); color: var(--primary); letter-spacing: -0.01em; }
.line-muted { display: block; color: var(--muted-foreground); }
.text-brand { color: var(--brand); }

/* ---------- 3. Layout primitives ---------- */
.container { width: min(100% - 2 * var(--gutter, clamp(1rem, 4vw, 2rem)), var(--container-xl)); margin-inline: auto; }
.container-wide { width: min(100% - 2 * clamp(1rem, 4vw, 2rem), var(--container-2xl)); margin-inline: auto; }
.container-narrow { width: min(100% - 2 * clamp(1rem, 4vw, 2rem), var(--container-md)); margin-inline: auto; }
.section { padding-block: clamp(3.5rem, 2rem + 6vw, 7.5rem); }
.section-head { display: grid; gap: 1rem; max-width: 44rem; margin-bottom: clamp(2rem, 1.5rem + 2vw, 3.5rem); }
.section-head.center { margin-inline: auto; text-align: center; justify-items: center; }
.stack { display: grid; gap: var(--gap, 1rem); }
.row { display: flex; flex-wrap: wrap; align-items: center; gap: var(--gap, 0.75rem); }
.divider { height: 1px; background: var(--border); border: 0; margin: 0; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* ---------- 4. Button ---------- */
.btn {
  --_h: 2.5rem;
  display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem;
  height: var(--_h); padding-inline: 1.05rem;
  border-radius: var(--radius-btn);
  border: 1px solid transparent;
  font-size: 0.875rem; font-weight: var(--btn-weight);
  text-transform: var(--btn-case); letter-spacing: var(--btn-tracking);
  white-space: nowrap; cursor: pointer; user-select: none;
  transition: background-color var(--duration-fast) var(--ease-standard), color var(--duration-fast) var(--ease-standard),
    border-color var(--duration-fast) var(--ease-standard), transform var(--duration-fast) var(--ease-standard), box-shadow var(--duration-fast);
}
.btn:active { transform: translateY(1px) scale(0.99); }
.btn:disabled, .btn[aria-disabled="true"] { opacity: 0.5; pointer-events: none; }
.btn svg { width: 1em; height: 1em; flex: none; }
.btn-sm { --_h: 2rem; padding-inline: 0.8rem; font-size: 0.8125rem; }
.btn-lg { --_h: 3rem; padding-inline: 1.4rem; font-size: 0.9375rem; }
.btn-icon { width: var(--_h); padding: 0; }
.btn-primary { background: var(--primary); color: var(--primary-foreground); }
.btn-primary:hover { background: color-mix(in srgb, var(--primary) 88%, var(--foreground)); }
.btn-secondary { background: var(--card); color: var(--foreground); border-color: var(--border); box-shadow: var(--shadow-sm); }
.btn-secondary:hover { background: var(--accent); }
.btn-outline { background: transparent; color: var(--foreground); border-color: var(--input); }
.btn-outline:hover { background: var(--accent); color: var(--accent-foreground); }
.btn-ghost { background: transparent; color: var(--foreground); }
.btn-ghost:hover { background: var(--accent); color: var(--accent-foreground); }
.btn-brand { background: var(--brand); color: var(--brand-foreground); }
.btn-brand:hover { background: color-mix(in srgb, var(--brand) 88%, var(--foreground)); }
.btn-destructive { background: var(--destructive); color: var(--destructive-foreground); }
.btn-link { background: none; height: auto; padding: 0; color: var(--primary); text-transform: none; letter-spacing: 0; }
.btn-link:hover { text-decoration: underline; text-underline-offset: 3px; }
.btn .spinner { width: 1em; height: 1em; border-radius: 50%; border: 2px solid currentColor; border-right-color: transparent; animation: spin 0.7s linear infinite; }
.btn.is-loading { pointer-events: none; opacity: 0.85; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------- 5. Badge / eyebrow / kbd ---------- */
.badge {
  display: inline-flex; align-items: center; gap: 0.35rem;
  height: 1.375rem; padding-inline: 0.55rem;
  border-radius: 999px; border: 1px solid transparent;
  font-size: 0.75rem; font-weight: 500; line-height: 1; white-space: nowrap;
  background: var(--primary); color: var(--primary-foreground);
}
.badge-secondary { background: var(--secondary); color: var(--secondary-foreground); }
.badge-outline { background: transparent; color: var(--foreground); border-color: var(--border); }
.badge-soft { background: var(--accent); color: var(--accent-foreground); }
.badge-success { background: color-mix(in srgb, var(--success) 14%, var(--card)); color: color-mix(in srgb, var(--success) 70%, var(--foreground)); }
.badge-warning { background: color-mix(in srgb, var(--warning) 22%, var(--card)); color: color-mix(in srgb, var(--warning) 45%, var(--foreground)); }
.badge-destructive { background: color-mix(in srgb, var(--destructive) 13%, var(--card)); color: color-mix(in srgb, var(--destructive) 80%, var(--foreground)); }
.badge .dot { width: 6px; height: 6px; border-radius: 50%; background: currentColor; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 0.5rem;
  padding: 0.3rem 0.75rem 0.3rem 0.4rem;
  border: 1px solid var(--border); border-radius: 999px; background: var(--card);
  font-size: 0.8125rem; color: var(--muted-foreground); box-shadow: var(--shadow-sm);
}
.eyebrow b { font-weight: 500; color: var(--foreground); }
.eyebrow .badge { height: 1.25rem; font-size: 0.6875rem; }
.eyebrow svg { width: 14px; height: 14px; }
.kbd { font-family: var(--font-mono); font-size: 0.6875rem; padding: 0.1rem 0.35rem; border: 1px solid var(--border); border-bottom-width: 2px; border-radius: 4px; background: var(--muted); color: var(--muted-foreground); }

/* ---------- 6. Form controls ---------- */
.field { display: grid; gap: 0.4rem; }
.label { font-size: 0.875rem; font-weight: 500; }
.hint { font-size: 0.8125rem; color: var(--muted-foreground); }
.input, .textarea, .select {
  width: 100%; min-height: 2.5rem; padding: 0.55rem 0.8rem;
  background: var(--card); color: var(--foreground);
  border: 1px solid var(--input); border-radius: calc(var(--radius) - 2px);
  font-size: 0.9375rem;
  transition: border-color var(--duration-fast), box-shadow var(--duration-fast);
}
.input::placeholder, .textarea::placeholder { color: color-mix(in srgb, var(--muted-foreground) 75%, transparent); }
.input:focus, .textarea:focus, .select:focus { outline: none; border-color: var(--ring); box-shadow: 0 0 0 3px color-mix(in srgb, var(--ring) 22%, transparent); }
.textarea { min-height: 6rem; resize: vertical; line-height: 1.5; }
.select { appearance: none; padding-right: 2.25rem; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='none' stroke='%23888' stroke-width='2' viewBox='0 0 24 24'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 0.7rem center; }
.field.is-invalid .input, .field.is-invalid .textarea { border-color: var(--destructive); }
.field.is-invalid .input:focus { box-shadow: 0 0 0 3px color-mix(in srgb, var(--destructive) 20%, transparent); }
.field .error { display: none; font-size: 0.8125rem; color: var(--destructive); }
.field.is-invalid .error { display: block; }
.input-group { display: flex; gap: 0.5rem; }
.input-group .input { flex: 1; min-width: 0; }
.check { display: inline-flex; align-items: center; gap: 0.55rem; font-size: 0.9375rem; cursor: pointer; min-height: 2rem; }
.check input { accent-color: var(--primary); width: 1rem; height: 1rem; margin: 0; }
.switch { position: relative; display: inline-flex; align-items: center; gap: 0.6rem; cursor: pointer; font-size: 0.9375rem; min-height: 2rem; }
.switch input { position: absolute; opacity: 0; width: 1px; height: 1px; }
.switch .track { width: 2.25rem; height: 1.3rem; border-radius: 999px; background: var(--input); position: relative; transition: background var(--duration-base) var(--ease-standard); flex: none; }
.switch .track::after { content: ""; position: absolute; top: 2px; left: 2px; width: calc(1.3rem - 4px); height: calc(1.3rem - 4px); border-radius: 50%; background: var(--card); box-shadow: var(--shadow-sm); transition: transform var(--duration-base) var(--ease-spring); }
.switch input:checked + .track { background: var(--primary); }
.switch input:checked + .track::after { transform: translateX(0.95rem); }
.switch input:focus-visible + .track { outline: 2px solid var(--ring); outline-offset: 2px; }
.segmented { display: inline-flex; padding: 3px; gap: 2px; background: var(--muted); border: 1px solid var(--border); border-radius: calc(var(--radius-btn) + 3px); }
.segmented button { border: 0; background: none; height: 2rem; padding-inline: 0.9rem; border-radius: var(--radius-btn); font-size: 0.8125rem; font-weight: 500; color: var(--muted-foreground); cursor: pointer; }
.segmented button[aria-pressed="true"] { background: var(--card); color: var(--foreground); box-shadow: var(--shadow-sm); }

/* ---------- 7. Card ---------- */
.card { background: var(--card); color: var(--card-foreground); border: 1px solid var(--border); border-radius: var(--radius-card); }
.card-body { padding: clamp(1.1rem, 1rem + 0.6vw, 1.5rem); display: grid; gap: 0.6rem; }
.card-header { padding: 1rem 1.25rem; border-bottom: 1px solid var(--border); display: flex; align-items: center; justify-content: space-between; gap: 1rem; }
.card-raised { box-shadow: var(--shadow-md); }
.card-interactive { transition: border-color var(--duration-base), transform var(--duration-base) var(--ease-out), box-shadow var(--duration-base); }
.card-interactive:hover { border-color: color-mix(in srgb, var(--foreground) 22%, var(--border)); transform: translateY(-2px); box-shadow: var(--shadow-md); }
.icon-tile { width: 2.25rem; height: 2.25rem; border-radius: calc(var(--radius) - 2px); display: grid; place-items: center; background: var(--accent); color: var(--accent-foreground); }
.icon-tile svg { width: 18px; height: 18px; }

/* ---------- 8. Tabs ---------- */
.tabs { display: grid; gap: 1rem; }
.tab-list { display: inline-flex; gap: 2px; padding: 3px; background: var(--muted); border-radius: calc(var(--radius) + 2px); border: 1px solid var(--border); width: max-content; max-width: 100%; overflow-x: auto; }
.tab { border: 0; background: none; height: 2rem; padding-inline: 0.85rem; border-radius: calc(var(--radius) - 1px); font-size: 0.8125rem; font-weight: 500; color: var(--muted-foreground); cursor: pointer; white-space: nowrap; transition: color var(--duration-fast); }
.tab:hover { color: var(--foreground); }
.tab[aria-selected="true"] { background: var(--card); color: var(--foreground); box-shadow: var(--shadow-sm); }
.tab-panel[hidden] { display: none; }
.tab-panel { animation: fade-in var(--duration-base) var(--ease-out); }
.tab-list.underline { background: none; border: 0; border-bottom: 1px solid var(--border); border-radius: 0; padding: 0; gap: 1.25rem; width: 100%; }
.tab-list.underline .tab { border-radius: 0; padding-inline: 0; height: 2.5rem; box-shadow: none; background: none; border-bottom: 2px solid transparent; margin-bottom: -1px; }
.tab-list.underline .tab[aria-selected="true"] { border-color: var(--foreground); }
@keyframes fade-in { from { opacity: 0; transform: translateY(4px); } }

/* ---------- 9. Avatar ---------- */
.avatar { width: 2.25rem; height: 2.25rem; border-radius: 50%; display: grid; place-items: center; flex: none; font-size: 0.8125rem; font-weight: 600; color: var(--foreground); background: var(--secondary); border: 2px solid var(--card); overflow: hidden; }
.avatar-sm { width: 1.75rem; height: 1.75rem; font-size: 0.6875rem; }
.avatar-stack { display: flex; }
.avatar-stack .avatar + .avatar { margin-left: -0.55rem; }
.avatar.c1 { background: color-mix(in srgb, var(--chart-1) 22%, var(--card)); }
.avatar.c2 { background: color-mix(in srgb, var(--chart-2) 30%, var(--card)); }
.avatar.c3 { background: color-mix(in srgb, var(--chart-3) 30%, var(--card)); }
.avatar.c4 { background: color-mix(in srgb, var(--chart-4) 40%, var(--card)); }

/* ---------- 10. Accordion ---------- */
.accordion { border-top: 1px solid var(--border); }
.accordion details { border-bottom: 1px solid var(--border); }
.accordion summary { list-style: none; cursor: pointer; display: flex; justify-content: space-between; align-items: center; gap: 1rem; padding: 1.1rem 0; font-weight: 500; font-size: 1rem; }
.accordion summary::-webkit-details-marker { display: none; }
.accordion summary::after { content: ""; width: 10px; height: 10px; flex: none; border-right: 1.5px solid currentColor; border-bottom: 1.5px solid currentColor; transform: rotate(45deg) translate(-2px, -2px); transition: transform var(--duration-base) var(--ease-out); opacity: 0.6; }
.accordion details[open] summary::after { transform: rotate(-135deg) translate(-2px, -2px); }
.accordion .acc-body { padding: 0 0 1.2rem; color: var(--muted-foreground); max-width: 40rem; animation: fade-in var(--duration-base) var(--ease-out); }

/* ---------- 11. Dialog / sheet ---------- */
.dialog { border: 1px solid var(--border); border-radius: calc(var(--radius-card) + 2px); padding: 0; width: min(92vw, 28rem); background: var(--popover); color: var(--popover-foreground); box-shadow: var(--shadow-lg); }
.dialog::backdrop { background: color-mix(in srgb, var(--foreground) 35%, transparent); backdrop-filter: blur(2px); }
.dialog[open] { animation: pop-in var(--duration-base) var(--ease-out); }
.dialog .dialog-body { padding: 1.5rem; display: grid; gap: 1rem; }
.dialog .dialog-foot { padding: 1rem 1.5rem; border-top: 1px solid var(--border); display: flex; justify-content: flex-end; gap: 0.5rem; background: var(--muted); border-radius: 0 0 inherit inherit; }
@keyframes pop-in { from { opacity: 0; transform: translateY(8px) scale(0.98); } }
.sheet { position: fixed; inset: 0 0 0 auto; width: min(86vw, 22rem); background: var(--popover); border-left: 1px solid var(--border); z-index: 60; transform: translateX(100%); transition: transform var(--duration-slow) var(--ease-out); padding: 1.25rem; display: grid; align-content: start; gap: 0.25rem; }
.sheet.open { transform: none; box-shadow: var(--shadow-lg); }
.sheet a { padding: 0.8rem 0.25rem; border-bottom: 1px solid var(--border); font-size: 1.0625rem; }
.scrim { position: fixed; inset: 0; background: color-mix(in srgb, var(--foreground) 30%, transparent); z-index: 55; opacity: 0; pointer-events: none; transition: opacity var(--duration-base); }
.scrim.open { opacity: 1; pointer-events: auto; }

/* ---------- 12. Toast ---------- */
.toast-region { position: fixed; z-index: 80; bottom: 1rem; right: 1rem; left: 1rem; display: grid; justify-items: end; gap: 0.5rem; pointer-events: none; }
.toast { pointer-events: auto; display: flex; gap: 0.75rem; align-items: flex-start; width: min(100%, 22rem); padding: 0.85rem 1rem; background: var(--popover); color: var(--popover-foreground); border: 1px solid var(--border); border-radius: var(--radius-card); box-shadow: var(--shadow-lg); font-size: 0.875rem; animation: toast-in var(--duration-slow) var(--ease-spring); }
.toast b { display: block; font-weight: 600; }
.toast .t-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--success); margin-top: 0.4rem; flex: none; }
.toast.leaving { animation: toast-out var(--duration-base) var(--ease-standard) forwards; }
@keyframes toast-in { from { opacity: 0; transform: translateY(12px) scale(0.97); } }
@keyframes toast-out { to { opacity: 0; transform: translateX(16px); } }

/* ---------- 13. Tooltip ---------- */
[data-tip] { position: relative; }
[data-tip]::after { content: attr(data-tip); position: absolute; bottom: calc(100% + 8px); left: 50%; translate: -50% 4px; padding: 0.3rem 0.55rem; border-radius: 6px; background: var(--foreground); color: var(--background); font-size: 0.75rem; white-space: nowrap; opacity: 0; pointer-events: none; transition: opacity var(--duration-fast), translate var(--duration-fast); text-transform: none; letter-spacing: 0; font-weight: 500; z-index: 5; }
[data-tip]:hover::after, [data-tip]:focus-visible::after { opacity: 1; translate: -50% 0; }

/* ---------- 14. Table ---------- */
.table-wrap { overflow-x: auto; border: 1px solid var(--border); border-radius: var(--radius-card); background: var(--card); }
.table { width: 100%; border-collapse: collapse; font-size: 0.875rem; font-variant-numeric: tabular-nums; }
.table th { text-align: left; font-weight: 500; color: var(--muted-foreground); font-size: 0.8125rem; padding: 0.7rem 1rem; border-bottom: 1px solid var(--border); white-space: nowrap; }
.table td { padding: 0.75rem 1rem; border-bottom: 1px solid var(--border); white-space: nowrap; }
.table tr:last-child td { border-bottom: 0; }
.table tbody tr { transition: background var(--duration-fast); }
.table tbody tr:hover { background: color-mix(in srgb, var(--muted) 60%, transparent); }

/* ---------- 15. Site navigation (product nav, not doc nav) ---------- */
.site-nav { position: sticky; top: 0; z-index: 40; background: color-mix(in srgb, var(--background) 82%, transparent); backdrop-filter: saturate(1.4) blur(12px); -webkit-backdrop-filter: saturate(1.4) blur(12px); border-bottom: 1px solid transparent; transition: border-color var(--duration-base); }
.site-nav.scrolled { border-bottom-color: var(--border); }
.site-nav .nav-inner { display: flex; align-items: center; gap: 1.5rem; height: 4rem; }
.site-nav .logo { display: inline-flex; align-items: center; gap: 0.5rem; font-weight: 600; letter-spacing: -0.02em; font-size: 1.0625rem; white-space: nowrap; }
.site-nav .logo-mark { width: 1.5rem; height: 1.5rem; flex: none; }
.site-nav .nav-links { display: none; gap: 0.25rem; margin-inline: auto; }
.site-nav .nav-links a { padding: 0.45rem 0.75rem; font-size: 0.875rem; color: var(--muted-foreground); border-radius: var(--radius-btn); transition: color var(--duration-fast), background var(--duration-fast); }
.site-nav .nav-links a:hover, .site-nav .nav-links a[aria-current="page"] { color: var(--foreground); background: var(--accent); }
.site-nav .nav-actions { display: flex; align-items: center; gap: 0.5rem; margin-left: auto; }
.site-nav .nav-actions .hide-sm { display: none; }
.site-nav .menu-btn { display: inline-flex; }
@media (min-width: 900px) {
  .site-nav .nav-links { display: flex; }
  .site-nav .nav-actions { margin-left: 0; }
  .site-nav .nav-actions .hide-sm { display: inline-flex; }
  .site-nav .menu-btn { display: none; }
}
/* floating pill variant (portfolio) */
.site-nav.float { background: none; backdrop-filter: none; -webkit-backdrop-filter: none; border: 0; padding-top: 0.9rem; }
.site-nav.float .nav-inner { height: auto; justify-content: center; }
.site-nav.float .pill { display: inline-flex; align-items: center; gap: 0.15rem; padding: 0.3rem; border: 1px solid var(--border); border-radius: 999px; background: color-mix(in srgb, var(--card) 85%, transparent); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); box-shadow: var(--shadow-sm); max-width: 100%; overflow-x: auto; }
.site-nav.float .pill a { padding: 0.4rem 0.8rem; border-radius: 999px; font-size: 0.8125rem; color: var(--muted-foreground); white-space: nowrap; }
.site-nav.float .pill a[aria-current="page"] { background: var(--secondary); color: var(--foreground); font-weight: 500; }
.site-nav.float .pill a:hover { color: var(--foreground); }

/* ---------- 16. Utility: reveal on scroll ---------- */
.reveal { opacity: 0; transform: translateY(14px); transition: opacity var(--duration-story) var(--ease-out), transform var(--duration-story) var(--ease-out); transition-delay: calc(var(--i, 0) * 70ms); }
.reveal.in { opacity: 1; transform: none; }
.no-js .reveal { opacity: 1; transform: none; }