/*
  FLIGHT TOOLS — SHARED STYLESHEET
  ─────────────────────────────────
  The one stylesheet every PHP page loads (via shared/head.php). Tool pages add
  their own small file on top ($extraCss) for what is specific to that tool.

  Sections: 1 Fonts · 2 Tokens · 3 Base · 4 Accessibility · 5 Layout · 6 Nav ·
            7 Footer · 8 Components (button, form, card, table, modal, badge,
            toggle, notice) · 9 Page furniture · 10 Error pages · 11 Utilities

  Breakpoints used across the site:  880px tablets · 720px nav collapses · 560px phones
*/

/* ── 1. Fonts (self-hosted, Latin subset; paths relative to this file so the folder can sit anywhere) ── */
@font-face { font-family: 'DM Sans'; font-style: normal; font-weight: 400; font-display: swap; src: url('fonts/dm-sans-latin-400.woff2') format('woff2'); unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD; }
@font-face { font-family: 'DM Sans'; font-style: normal; font-weight: 500; font-display: swap; src: url('fonts/dm-sans-latin-500.woff2') format('woff2'); unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD; }
@font-face { font-family: 'DM Sans'; font-style: normal; font-weight: 600; font-display: swap; src: url('fonts/dm-sans-latin-600.woff2') format('woff2'); unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD; }
@font-face { font-family: 'Space Grotesk'; font-style: normal; font-weight: 600; font-display: swap; src: url('fonts/space-grotesk-latin-600.woff2') format('woff2'); unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD; }
@font-face { font-family: 'Space Grotesk'; font-style: normal; font-weight: 700; font-display: swap; src: url('fonts/space-grotesk-latin-700.woff2') format('woff2'); unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD; }
@font-face { font-family: 'JetBrains Mono'; font-style: normal; font-weight: 400; font-display: swap; src: url('fonts/jetbrains-mono-latin-400.woff2') format('woff2'); unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD; }
@font-face { font-family: 'JetBrains Mono'; font-style: normal; font-weight: 500; font-display: swap; src: url('fonts/jetbrains-mono-latin-500.woff2') format('woff2'); unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD; }
@font-face { font-family: 'JetBrains Mono'; font-style: normal; font-weight: 600; font-display: swap; src: url('fonts/jetbrains-mono-latin-600.woff2') format('woff2'); unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD; }

/* ── 2. Tokens ── */
:root {
  /* surfaces */
  --bg:              #0a0a0d;
  --bg-elevated:     #101014;
  --surface:         #17171d;
  --surface-2:       #1e1e26;
  --border:          rgba(255,255,255,.08);
  --border-strong:   rgba(255,255,255,.16);

  /* ink */
  --ink:             #f2f1f7;
  --ink-muted:       rgba(242,241,247,.64);
  --ink-dim:         rgba(242,241,247,.40);

  /* accent */
  --accent:          #8b7fd6;
  --accent-strong:   #a89bef;
  --accent-soft:     rgba(139,127,214,.14);
  --accent-border:   rgba(139,127,214,.32);
  --accent-line:     rgba(139,127,214,.20);   /* hairlines and table rules */
  --accent-line-strong: rgba(139,127,214,.42);
  --accent-ink:      #100e1c;                 /* text on a solid accent fill */

  /* semantic */
  --success:         #74bf93;
  --success-soft:    rgba(116,191,147,.12);
  --warning:         #d9a75b;
  --warning-soft:    rgba(217,167,91,.12);
  --danger:          #d97088;
  --danger-soft:     rgba(217,112,136,.12);

  /* type */
  --font-display:    'Space Grotesk', system-ui, sans-serif;
  --font-body:       'DM Sans', system-ui, -apple-system, sans-serif;
  --font-mono:       'JetBrains Mono', ui-monospace, 'SF Mono', monospace;

  --text-2xs:  .6875rem;   /* 11px */
  --text-xs:   .75rem;     /* 12px */
  --text-sm:   .875rem;    /* 14px */
  --text-base: 1rem;       /* 16px */
  --text-lg:   1.125rem;
  --text-xl:   1.375rem;
  --text-2xl:  clamp(1.75rem, 2.4vw, 2.25rem);
  --text-3xl:  clamp(2.25rem, 3.6vw, 3rem);
  --text-hero: clamp(2.75rem, 6.2vw, 5.75rem);

  --tracking-tight:  -.01em;
  --tracking-wide:   .06em;
  --tracking-widest: .22em;

  /* spacing (4px base) */
  --space-1: .25rem;  --space-2: .5rem;  --space-3: .75rem;  --space-4: 1rem;
  --space-5: 1.5rem;  --space-6: 2rem;   --space-7: 3rem;    --space-8: 4rem;
  --space-9: 6rem;    --space-10: 8rem;

  /* shape and depth */
  --radius-sm:   8px;
  --radius-md:   12px;
  --radius-lg:   20px;
  --radius-full: 999px;
  --radius:      var(--radius-md);            /* default control radius */
  --shadow-sm:   0 1px 0 rgba(255,255,255,.03) inset, 0 8px 20px rgba(0,0,0,.28);
  --shadow-md:   0 1px 0 rgba(255,255,255,.04) inset, 0 20px 48px rgba(0,0,0,.4);
  --shadow-lg:   0 1px 0 rgba(255,255,255,.05) inset, 0 32px 80px rgba(0,0,0,.5);
  --shadow:      var(--shadow-sm);

  /* motion */
  --ease-out:       cubic-bezier(.16,.82,.26,1);
  --duration-fast:  .18s;
  --duration-base:  .32s;

  /* layout */
  --max-width:     1200px;
  --nav-height:    60px;
  --footer-height: 44px;
}

/* ── 3. Base ── */
*, *::before, *::after { box-sizing: border-box; }
html {
  min-height: 100%;
  background: var(--bg);
  color-scheme: dark;
  -webkit-text-size-adjust: 100%;
  scrollbar-width: thin;
  scrollbar-color: var(--accent-line) transparent;
}
body {
  margin: 0;
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
  overflow-x: clip;
}
main { flex: 1 0 auto; }
h1, h2, h3, h4 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.08;
  letter-spacing: var(--tracking-tight);
  color: var(--ink);
}
p { margin: 0; }
a { color: inherit; text-decoration: none; }
img, svg { max-width: 100%; display: block; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }
button, a { -webkit-tap-highlight-color: transparent; }
[hidden] { display: none !important; }
::selection { background: var(--accent-soft); color: var(--ink); }
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--accent-line); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--accent-border); }

/* ── 4. Accessibility ── */
:focus-visible { outline: 2px solid var(--accent-strong); outline-offset: 2px; }
.skip-link {
  position: absolute; left: var(--space-4); top: -120px; z-index: 200;
  padding: .6em 1em; border-radius: var(--radius-sm);
  background: var(--accent); color: var(--accent-ink);
  font-size: var(--text-sm); font-weight: 600;
}
.skip-link:focus { top: var(--space-3); }
.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;
}
/* Reduced motion, honoured on every page. The class is also set on <html> by
   shared/head.php so scripts can skip an animation instead of just shortening it. */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }
}

/* ── 5. Layout ── */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: clamp(20px, 4vw, 48px);
}
.section { padding-block: var(--space-9); }
.page    { padding-block: var(--space-7) var(--space-8); }   /* a tool page's <main> */
@media (max-width: 880px) { .section { padding-block: var(--space-8); } }
@media (max-width: 560px) { .section { padding-block: var(--space-7); } .page { padding-block: var(--space-6) var(--space-7); } }
.stack-4 { display: flex; flex-direction: column; gap: var(--space-4); }

/* ── 6. Nav ── */
.nav {
  position: sticky; top: 0; z-index: 60;
  height: var(--nav-height);
  display: flex; align-items: center;
  flex: none;
  background: rgba(10,10,13,.78);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
}
.nav-inner {
  width: 100%; max-width: var(--max-width); margin: 0 auto;
  padding-inline: clamp(20px, 4vw, 48px);
  display: flex; align-items: center; justify-content: space-between; gap: var(--space-5);
}
.nav-brand { display: flex; align-items: center; gap: var(--space-3); }
.brand-mark { width: 20px; height: 20px; color: var(--accent-strong); flex: none; }
.brand-word {
  font-family: var(--font-mono); font-size: var(--text-xs); font-weight: 600;
  letter-spacing: var(--tracking-widest); text-transform: uppercase; color: var(--ink);
}
.nav-links { display: flex; align-items: center; gap: clamp(20px, 3vw, 40px); }
.nav-links a {
  position: relative; padding: var(--space-2) 0;
  font-family: var(--font-mono); font-size: var(--text-2xs); font-weight: 500;
  letter-spacing: var(--tracking-wide); text-transform: uppercase; color: var(--ink-muted);
  transition: color var(--duration-fast) ease;
}
.nav-links a::after {
  content: ''; position: absolute; left: 0; right: 100%; bottom: 0; height: 1px;
  background: var(--accent-strong);
  transition: right var(--duration-base) var(--ease-out);
}
.nav-links a:hover, .nav-links a:focus-visible { color: var(--ink); }
.nav-links a:hover::after, .nav-links a:focus-visible::after { right: 0; }
.nav-links a[aria-current="page"] { color: var(--ink); }
.nav-links a[aria-current="page"]::after { right: 0; }
.nav-brand[aria-current="page"] .brand-word { color: var(--accent-strong); }
.nav-toggle {
  display: none; width: 40px; height: 40px; margin-right: -8px;
  align-items: center; justify-content: center;
  border-radius: var(--radius-sm); color: var(--ink-muted);
}
.nav-toggle svg { width: 22px; height: 22px; }
.nav-toggle:hover { color: var(--ink); }
@media (max-width: 720px) {
  .js .nav-toggle { display: inline-flex; }
  .js .nav-links {
    display: none; position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    padding: var(--space-2) clamp(20px, 4vw, 48px) var(--space-4);
    background: rgba(10,10,13,.97); border-bottom: 1px solid var(--border);
  }
  .js .nav[data-open] .nav-links { display: flex; }
  .js .nav-links a { padding: var(--space-3) 0; font-size: var(--text-xs); border-bottom: 1px solid var(--border); }
  .js .nav-links a:last-child { border-bottom: 0; }
  .js .nav-links a::after { display: none; }
  .js .nav-links a[aria-current="page"] { color: var(--accent-strong); }
}

/* ── 7. Footer ── */
.site-footer { flex: none; margin-top: auto; border-top: 1px solid var(--border); min-height: var(--footer-height); display: flex; align-items: center; }
.site-footer-inner {
  display: flex; justify-content: space-between; align-items: center;
  gap: var(--space-2) var(--space-5); flex-wrap: wrap; padding-block: var(--space-3);
  font-family: var(--font-mono); font-size: var(--text-2xs); letter-spacing: var(--tracking-wide); color: var(--ink-dim);
}
.site-footer small { font-size: inherit; }
.site-footer .admin-link { margin-left: var(--space-3); color: var(--ink-dim); transition: color var(--duration-fast) ease; }
.site-footer .admin-link:hover, .site-footer .admin-link:focus-visible { color: var(--ink-muted); text-decoration: underline; }

/* ── 8. Components ── */

/* Button: .btn + one of .btn-primary / .btn-ghost; .btn-sm / .btn-lg for size.
   .primary, .small and .btn-outline are the older names that JS-built markup still uses. */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2);
  padding: .65em 1.2em;
  border: 1px solid transparent; border-radius: var(--radius);
  background: transparent; color: var(--ink);
  font-family: var(--font-body); font-size: var(--text-sm); font-weight: 600; line-height: 1.2;
  white-space: nowrap; cursor: pointer;
  transition: background var(--duration-fast) ease, border-color var(--duration-fast) ease,
              color var(--duration-fast) ease, transform var(--duration-fast) var(--ease-out);
}
.btn:active { transform: scale(.98); }
.btn:disabled, .btn[aria-disabled="true"] { opacity: .5; cursor: not-allowed; transform: none; }
.btn-primary, .btn.primary { background: var(--accent); color: var(--accent-ink); }
.btn-primary:hover, .btn-primary:focus-visible, .btn.primary:hover { background: var(--accent-strong); }
.btn-ghost, .btn-outline { border-color: var(--border-strong); color: var(--ink); }
.btn-ghost:hover, .btn-ghost:focus-visible, .btn-outline:hover { border-color: var(--accent-border); background: var(--accent-soft); }
.btn-sm, .btn.small { padding: .4em .8em; font-size: var(--text-xs); }
.btn-lg { padding: .85em 1.6em; }

/* Forms */
.field { display: flex; flex-direction: column; gap: var(--space-2); }
.field label, .label {
  display: block; font-size: var(--text-xs); font-weight: 500; color: var(--ink-muted);
}
.input, .select {
  width: 100%; padding: .65em .85em;
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong); border-radius: var(--radius-sm);
  color: var(--ink); font-family: var(--font-body); font-size: var(--text-sm);
  font-variant-numeric: tabular-nums;
  transition: border-color var(--duration-fast) ease, background var(--duration-fast) ease;
}
.input:focus, .select:focus { border-color: var(--accent-border); background: var(--surface); }
.input:disabled, .select:disabled { opacity: .55; cursor: not-allowed; }
.input::placeholder { color: var(--ink-dim); }
.select {
  appearance: none; -webkit-appearance: none; cursor: pointer; padding-right: 2.2em;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6'%3E%3Cpath d='M1 1l4 4 4-4' stroke='%238b8b95' stroke-width='1.5' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat; background-position: right .85em center;
}
.select:focus { background-color: var(--surface); }
textarea.input { resize: vertical; line-height: 1.5; }

/* Card / panel: one surface, used for the outer card and for stand-alone panels */
.card, .panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
}

/* Table */
.table-wrap { overflow-x: auto; border: 1px solid var(--border); border-radius: var(--radius-md); background: var(--bg-elevated); }
.table { width: 100%; border-collapse: collapse; font-size: var(--text-sm); }
.table th {
  text-align: left; padding: var(--space-3);
  font-family: var(--font-mono); font-size: var(--text-2xs); font-weight: 500;
  letter-spacing: var(--tracking-wide); text-transform: uppercase; color: var(--ink-dim);
  border-bottom: 1px solid var(--border-strong);
}
.table td { padding: var(--space-3); border-bottom: 1px solid var(--border); color: var(--ink-muted); }
.table tr:last-child td { border-bottom: 0; }

/* Editable admin table (fleet roster, syllabus) */
table.admin { border-collapse: collapse; width: 100%; font-size: var(--text-sm); }
table.admin th, table.admin td { padding: .5em .6em; border-bottom: 1px solid var(--border); }
table.admin th {
  text-align: left; color: var(--ink-dim); font-family: var(--font-mono);
  font-size: var(--text-2xs); text-transform: uppercase; letter-spacing: var(--tracking-wide);
  position: sticky; top: 0; background: var(--surface);
}
table.admin input[type=text], table.admin input[type=number], table.admin select {
  width: 100%; background: var(--bg-elevated); border: 1px solid var(--border-strong);
  color: var(--ink); border-radius: 4px; padding: .35em .5em; font-size: var(--text-sm);
}
table.admin input[type=text], table.admin input[type=number] { font-family: var(--font-mono); }
table.admin tr.dirty td { background: var(--accent-soft); }

/* Modal: <div class="modal-backdrop" [.open]><div class="modal">…</div></div> */
.modal-backdrop {
  display: none; position: fixed; inset: 0; z-index: 100;
  align-items: center; justify-content: center; padding: var(--space-4);
  background: rgba(0,0,0,.74);
  backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
}
.modal-backdrop.open { display: flex; }
.modal {
  width: 100%; max-width: 440px; max-height: calc(100dvh - 2 * var(--space-4)); overflow: auto;
  background: var(--surface); border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg); box-shadow: var(--shadow-lg);
  animation: modal-in var(--duration-base) var(--ease-out);
}
@keyframes modal-in { from { transform: translateY(-12px) scale(.98); opacity: 0; } to { transform: none; opacity: 1; } }

/* Badge */
.badge {
  display: inline-flex; align-items: center; gap: var(--space-1);
  padding: .15em .65em; border-radius: var(--radius-full);
  border: 1px solid var(--accent-border); background: var(--accent-soft); color: var(--accent-strong);
  font-family: var(--font-mono); font-size: var(--text-2xs); font-weight: 500; line-height: 1.6;
  letter-spacing: var(--tracking-wide); text-transform: uppercase; white-space: nowrap;
}
.badge-success { border-color: rgba(116,191,147,.35); background: var(--success-soft); color: var(--success); }
.badge-warning { border-color: rgba(217,167,91,.35);  background: var(--warning-soft); color: var(--warning); }
.badge-danger  { border-color: rgba(217,112,136,.35); background: var(--danger-soft);  color: var(--danger); }

/* Toggle: segmented control. Children are buttons or links; the active one carries
   .active, aria-pressed="true" or aria-current="page". */
.toggle {
  display: inline-flex; overflow: hidden;
  border: 1px solid var(--border-strong); border-radius: var(--radius-sm);
  background: var(--bg-elevated);
}
.toggle > button, .toggle > a {
  display: inline-flex; align-items: center; justify-content: center;
  padding: .65em 1.1em;
  border: 0; border-left: 1px solid var(--border); background: transparent;
  color: var(--ink-muted); cursor: pointer; white-space: nowrap; text-decoration: none;
  font-family: var(--font-mono); font-size: var(--text-2xs); font-weight: 500;
  letter-spacing: var(--tracking-wide); text-transform: uppercase;
  transition: color var(--duration-fast) ease, background var(--duration-fast) ease;
}
.toggle > :first-child { border-left: 0; }
.toggle > button:hover, .toggle > a:hover { color: var(--ink); }
.toggle > .active, .toggle > [aria-pressed="true"], .toggle > [aria-current="page"] {
  background: var(--accent-soft); color: var(--accent-strong);
  box-shadow: inset 0 -2px 0 var(--accent-strong);
}
.toggle > :focus-visible { outline-offset: -2px; }

/* Notice: one inline message style for loading / empty / error / success states */
.notice {
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--border-strong); border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm); background: var(--surface);
  color: var(--ink-muted); font-size: var(--text-sm); line-height: 1.5;
}
.notice-error   { border-left-color: var(--danger);  background: var(--danger-soft);  color: var(--ink); }
.notice-success { border-left-color: var(--success); background: var(--success-soft); color: var(--ink); }
.notice-warning { border-left-color: var(--warning); background: var(--warning-soft); color: var(--ink); }

/* ── 9. Page furniture ── */
.eyebrow {
  display: inline-flex; align-items: center; gap: var(--space-2);
  font-family: var(--font-mono); font-size: var(--text-2xs); font-weight: 500;
  letter-spacing: var(--tracking-widest); text-transform: uppercase; color: var(--ink-dim);
}
.eyebrow::before {
  content: ''; width: 5px; height: 5px; flex: none; border-radius: var(--radius-full);
  background: var(--accent); box-shadow: 0 0 8px var(--accent-border);
}
.page-title { font-size: var(--text-3xl); margin-bottom: var(--space-2); }
.page-sub { max-width: 62ch; margin-bottom: var(--space-6); color: var(--ink-muted); }
.section-heading { font-size: var(--text-xl); margin-bottom: var(--space-3); }
.hint { color: var(--ink-dim); font-size: var(--text-xs); }
.status-line {
  min-height: 1.2em; margin-top: var(--space-4);
  font-family: var(--font-mono); font-size: var(--text-xs); color: var(--ink-dim);
}
.status-line.error { color: var(--danger); }
.status-line.ok { color: var(--success); }
.admin-toolbar { display: flex; align-items: center; gap: var(--space-4); flex-wrap: wrap; margin-bottom: var(--space-4); }
.icon-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 1.9em; height: 1.9em; line-height: 1;
  border: 1px solid var(--border-strong); border-radius: var(--radius-sm);
  color: var(--ink-muted); font-size: var(--text-base);
  transition: border-color var(--duration-fast) ease, color var(--duration-fast) ease, background var(--duration-fast) ease;
}
.icon-btn:hover, .icon-btn:focus-visible { border-color: var(--danger); color: var(--danger); background: var(--danger-soft); }

/* ── 10. Error pages (404 / 403 PHP, 500 static) ── */
.error-page {
  display: flex; flex-direction: column; align-items: flex-start; justify-content: center;
  gap: var(--space-4); min-height: 60vh; padding-block: var(--space-9);
}
.error-code { font-family: var(--font-mono); font-size: var(--text-sm); letter-spacing: var(--tracking-widest); color: var(--accent-strong); }
.error-page h1 { font-size: var(--text-3xl); }
.error-text { max-width: 52ch; color: var(--ink-muted); }
.error-actions { display: flex; gap: var(--space-3); flex-wrap: wrap; margin-top: var(--space-3); }

/* ── 11. Utilities ── */
.hidden { display: none !important; }
.font-mono { font-family: var(--font-mono); font-feature-settings: 'tnum' 1, 'zero' 1; }