/* Base: reset, type styles, buttons, links, focus, form basics, utilities.
   Colors and type values come from tokens.css roles. Never use --gist-* here
   except where a role does not exist. */

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

html {
  height: 100%;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  /* Page side gutter: 16px on phones to 64px at 1440, never inside the safe area. */
  --gutter-l: max(16px, var(--space-gutter), env(safe-area-inset-left, 0px));
  --gutter-r: max(16px, var(--space-gutter), env(safe-area-inset-right, 0px));
  /* Full-width bars (header, Home) use these as side padding so their edges
     meet the .wrap column on screens wider than the layout max. The % is the
     element's containing block, which is the full width for both. */
  --edge-l: max(var(--gutter-l), calc((100% - var(--size-layout-max)) / 2 + var(--gutter-l)));
  --edge-r: max(var(--gutter-r), calc((100% - var(--size-layout-max)) / 2 + var(--gutter-r)));
  --header-h: var(--size-header);
  --ease-out: var(--motion-ease-out);
  --ease-expo: var(--motion-ease-out-expo);
  --hover: 240ms;
}

body {
  height: 100%;
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-text);
  font-size: var(--type-body-size);
  line-height: var(--type-body-leading);
  font-weight: var(--type-body-weight);
  font-stretch: 100%;
  font-kerning: normal;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  overflow-x: clip;
}

img, svg, video, canvas, iframe { display: block; max-width: 100%; }
img { height: auto; }
button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; background: none; border: 0; padding: 0; }
h1, h2, h3, h4, p, ul, ol, dl, dd, figure, blockquote { margin: 0; }
ul[role="list"], ol[role="list"] { list-style: none; padding: 0; }
[hidden] { display: none !important; }

::selection { background: var(--color-selection-bg); color: var(--color-selection-text); }

/* Themed areas set their own ground, as type-and-color.md section 3 asks. */
[data-theme] { background: var(--color-bg); color: var(--color-text); }

/* ---------- Focus ---------- */
/* A 2 px ring that pulls into focus: it starts wide and clear and settles onto
   the control in 240 ms, like pulling focus on a lens. Orange on the dark
   grounds, navy on light. --focus-offset moves it per control. */
:focus { outline: none; }
:focus-visible {
  outline: var(--border-focus-width) solid var(--color-focus);
  outline-offset: var(--focus-offset, var(--border-focus-offset));
  animation: focus-pull 240ms var(--motion-ease-out);
}
@keyframes focus-pull {
  from { outline-offset: calc(var(--focus-offset, var(--border-focus-offset)) + 7px); outline-color: transparent; }
}
[tabindex="-1"]:focus-visible { outline: none; animation: none; }

.skip-link {
  position: fixed;
  top: 12px;
  left: var(--gutter-l);
  z-index: 200;
  padding: var(--space-3) var(--space-5);
  background: var(--color-action);
  color: var(--color-on-action);
  font-stretch: 125%;
  font-weight: 700;
  font-size: var(--type-label-size);
  letter-spacing: var(--type-label-tracking);
  text-transform: uppercase;
  text-decoration: none;
  border-radius: var(--radius-control);
  transform: translateY(-160%);
  transition: transform var(--motion-duration-base) var(--ease-out);
}
.skip-link:focus-visible { transform: none; outline-color: var(--gist-cream); }

/* ---------- Type styles ---------- */
.t-display-1, .t-display-2, .t-display-3 {
  font-family: var(--font-display);
  font-stretch: 125%;
  font-weight: 800;
  text-wrap: balance;
}
.t-display-1 { font-size: var(--type-display-1-size); letter-spacing: var(--type-display-1-tracking); line-height: var(--type-display-1-leading); }
.t-display-2 { font-size: var(--type-display-2-size); letter-spacing: var(--type-display-2-tracking); line-height: var(--type-display-2-leading); }
.t-display-3 { font-size: var(--type-display-3-size); letter-spacing: var(--type-display-3-tracking); line-height: var(--type-display-3-leading); }
.t-h1 { font-size: var(--type-heading-1-size); font-stretch: 112.5%; font-weight: 700; letter-spacing: var(--type-heading-1-tracking); line-height: var(--type-heading-1-leading); text-wrap: balance; }
.t-h2 { font-size: var(--type-heading-2-size); font-stretch: 112.5%; font-weight: 700; letter-spacing: var(--type-heading-2-tracking); line-height: var(--type-heading-2-leading); text-wrap: balance; }
.t-h3 { font-size: var(--type-heading-3-size); font-stretch: 100%; font-weight: 600; line-height: var(--type-heading-3-leading); text-wrap: balance; }
.t-h4 { font-size: var(--type-heading-4-size); font-stretch: 100%; font-weight: 600; line-height: var(--type-heading-4-leading); }
.t-lead { font-size: var(--type-body-lead-size); line-height: var(--type-body-lead-leading); max-width: var(--size-measure-lead); text-wrap: pretty; }
.t-body { font-size: var(--type-body-size); line-height: var(--type-body-leading); max-width: var(--size-measure); text-wrap: pretty; }
.t-small { font-size: var(--type-body-small-size); line-height: var(--type-body-small-leading); letter-spacing: var(--type-body-small-tracking); }
.t-label, .t-label-sm {
  font-stretch: 125%;
  font-weight: 700;
  text-transform: uppercase;
  line-height: 1.2;
}
.t-label { font-size: var(--type-label-size); letter-spacing: var(--type-label-tracking); }
.t-label-sm { font-size: var(--type-label-small-size); letter-spacing: var(--type-label-small-tracking); }
.t-muted { color: var(--color-text-muted); }
.t-accent { color: var(--color-accent-text); }
.t-num { font-variant-numeric: tabular-nums; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.9em;
  font-stretch: 125%;
  font-weight: 700;
  font-size: var(--type-label-size);
  letter-spacing: var(--type-label-tracking);
  text-transform: uppercase;
  line-height: 1.2;
  color: var(--color-accent-text);
}
.eyebrow::before {
  content: "";
  width: 28px;
  height: var(--border-strong);
  background: var(--color-accent);
}

.prose > * + * { margin-top: var(--space-stack); }
.prose p { max-width: var(--size-measure); text-wrap: pretty; }
strong, b { font-weight: 600; }

/* ---------- Links ---------- */
a { color: var(--color-link); }
.link {
  color: var(--color-link);
  text-decoration: underline;
  text-decoration-color: var(--color-link-underline);
  text-decoration-thickness: var(--border-link-underline);
  text-underline-offset: var(--border-link-underline-offset);
  transition: text-decoration-color var(--hover) var(--ease-out), color var(--hover) var(--ease-out);
}
.link:hover { text-decoration-color: var(--color-text); }

/* Arrow link: caps label. On hover the underline grows from the left and
   leaves to the right, and the arrow nudges. */
.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 0.75em;
  min-height: var(--size-touch-min);
  color: var(--color-text);
  text-decoration: none;
  font-stretch: 125%;
  font-weight: 700;
  font-size: var(--type-label-size);
  letter-spacing: var(--type-label-tracking);
  text-transform: uppercase;
  line-height: 1.3;
}
.link-arrow span { background: linear-gradient(var(--color-accent), var(--color-accent)) 100% 100% / 0 var(--border-strong) no-repeat; padding-bottom: 3px; transition: background-size var(--hover) var(--ease-out); }
.link-arrow:hover span { background-size: 100% var(--border-strong); background-position: 0 100%; }
.link-arrow svg { flex: none; width: 16px; height: 16px; transition: transform var(--hover) var(--ease-out); }
.link-arrow:hover svg { transform: translateX(4px); }

/* ---------- Buttons ---------- */
/* Hover: a fill wipes in from the left and leaves to the right (the site's
   transition language in miniature), 280 ms. The arrow nudges. */
.btn {
  --btn-bg: transparent;
  --btn-fg: var(--color-text);
  --btn-border: transparent;
  --btn-fill: rgb(var(--gist-cream-rgb) / 0.1);
  position: relative;
  isolation: isolate;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.85em;
  min-height: var(--size-control);
  padding: 0 var(--space-5);
  border: var(--border-hairline) solid var(--btn-border);
  border-radius: var(--radius-control);
  background: var(--btn-bg);
  color: var(--btn-fg);
  font-stretch: 125%;
  font-weight: 700;
  font-size: var(--type-label-size);
  letter-spacing: var(--type-label-tracking);
  text-transform: uppercase;
  line-height: 1;
  text-decoration: none;
  white-space: nowrap;
  transition:
    background-color var(--hover) var(--ease-out),
    border-color 280ms var(--ease-out),
    color 280ms var(--ease-out),
    transform var(--motion-duration-instant) var(--ease-out);
  -webkit-tap-highlight-color: transparent;
}
.btn::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  border-radius: inherit;
  background: var(--btn-fill);
  transform: scaleX(0);
  transform-origin: right center;
  transition: transform 280ms var(--ease-out);
}
@media (hover: hover) {
  .btn:hover { color: var(--btn-fg-hover, var(--btn-fg)); border-color: var(--btn-border-hover, var(--btn-border)); }
  .btn:hover::before { transform: scaleX(1); transform-origin: left center; }
}
@media (prefers-reduced-motion: reduce) {
  .btn::before { transform: none; opacity: 0; transition-property: opacity; }
  .btn:hover::before { opacity: 1; }
}
.btn:active { transform: translateY(1px); }
@media (max-width: 520px) {
  .btn { white-space: normal; text-align: center; line-height: 1.25; padding-block: var(--space-2); max-width: 100%; }
}
.btn svg { width: 16px; height: 16px; flex: none; transition: transform var(--hover) var(--ease-out); }
.btn:hover svg { transform: translateX(4px); }
.btn--primary { --btn-bg: var(--color-action); --btn-fg: var(--color-on-action); --btn-border: var(--color-action); --btn-fill: var(--color-action-hover); --btn-border-hover: var(--color-action-hover); }
.btn--secondary { --btn-fg: var(--color-text); --btn-border: rgb(var(--gist-cream-rgb) / 0.55); --btn-fill: var(--gist-cream); --btn-fg-hover: var(--gist-ink); --btn-border-hover: var(--gist-cream); }
.btn--ghost { --btn-fg: var(--color-text); padding: 0 var(--space-3); }
.btn--sm { min-height: 40px; padding: 0 var(--space-4); }
[data-theme="light"] .btn--secondary { --btn-border: var(--color-text); --btn-fill: var(--gist-navy); --btn-fg-hover: var(--gist-cream); --btn-border-hover: var(--gist-navy); }

/* ---------- Copy-to-clipboard email ---------- */
.email {
  display: inline-flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2) var(--space-3);
}
.email__addr {
  font-stretch: 100%;
  font-weight: 600;
  user-select: all;
  -webkit-user-select: all;
  word-break: break-all;
}
.email__copy {
  display: inline-flex;
  align-items: center;
  gap: 0.5em;
  min-height: 36px;
  min-width: var(--size-touch-min);
  padding: 0 var(--space-3);
  border: var(--border-hairline) solid var(--color-line-strong);
  border-radius: var(--radius-control);
  font-stretch: 125%;
  font-weight: 700;
  font-size: var(--type-label-small-size);
  letter-spacing: var(--type-label-small-tracking);
  text-transform: uppercase;
  transition: border-color var(--hover) var(--ease-out), background-color var(--hover) var(--ease-out);
}
.email__copy:hover { border-color: var(--color-text); background: rgb(var(--gist-cream-rgb) / 0.06); }
.email__copy svg { width: 14px; height: 14px; }
.email__copy[data-state="done"] { border-color: var(--color-accent); }

/* ---------- Utilities ---------- */
.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}
.wrap {
  width: 100%;
  max-width: var(--size-layout-max);
  margin-inline: auto;
  padding-left: var(--gutter-l);
  padding-right: var(--gutter-r);
}
.hairline { border: 0; border-top: var(--border-hairline) solid var(--color-line); margin: 0; }