/* reset.css — the ~40 lines of normalize we actually need. */
*, *::before, *::after { box-sizing: border-box; }

html, body { height: 100%; }

/*
 * The app is a fixed 100vh grid; every pane scrolls inside itself, so the page
 * itself never should.
 */
body { overflow: hidden; }

/*
 * `hidden` sets display:none at the lowest specificity, so any class that sets
 * display — .viz__empty is display:flex — silently wins and the element stays
 * on screen. Every toggle in this app uses the hidden attribute, so it has to
 * actually win.
 */
[hidden] { display: none !important; }

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

ul[class], ol[class] { list-style: none; }

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

input, button, textarea, select {
  font: inherit;
  color: inherit;
  background: none;
  border: none;
}

button { cursor: pointer; }

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

code, pre, kbd, samp { font-family: var(--font-mono); }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/*
 * ── scrollbars ─────────────────────────────────────────────────────────────
 *
 * Every pane in this app scrolls inside itself, so the default scrollbar was
 * showing up a dozen times over: a grey rounded capsule in a grey trough, in an
 * interface that has no rounded corners and no grey troughs anywhere else.
 *
 * These follow the same rules as the rest of the surface — square, hairline
 * thin, drawn in theme tokens so they re-theme with everything else — and they
 * stay quiet until they are being used. Idle, the thumb is two steps above the
 * background and the track is not painted at all, so a pane that happens to
 * overflow reads as a single mark down its edge rather than a stripe. Hovering
 * the pane lifts it, hovering the bar lifts it again, dragging turns it the
 * accent colour.
 */

/* Firefox has no pseudo-elements for this; these two properties are the whole
   API it offers, and they get the same colours. */
* {
  scrollbar-width: thin;
  scrollbar-color: var(--scroll-thumb) transparent;
}

::-webkit-scrollbar { width: 10px; height: 10px; }

/* No trough, no corner block — the pane's own background shows through. */
::-webkit-scrollbar-track,
::-webkit-scrollbar-corner { background: transparent; }

::-webkit-scrollbar-thumb {
  /* background-color, not the `background` shorthand: the shorthand would reset
     background-clip and the inset below would be lost. */
  background-color: var(--scroll-thumb);
  /* A transparent border plus padding-box clipping leaves a 6px bar inside a
     10px gutter, which is a rule rather than a capsule. */
  border: 2px solid transparent;
  background-clip: padding-box;
}

/* Brighten for whoever is actually reaching for it. */
:hover::-webkit-scrollbar-thumb { background-color: var(--scroll-thumb-live); }
::-webkit-scrollbar-thumb:hover { background-color: var(--fg-2); }
::-webkit-scrollbar-thumb:active { background-color: var(--accent); }

/* No stepper arrows at the ends. Chrome only draws them when they are given a
   size, but Edge on Windows will, and one OS-blue triangle undoes the lot. */
::-webkit-scrollbar-button { display: none; width: 0; height: 0; }

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