/* ============================================================
   PERLIN STUDIO — Signal Chamber stylesheet
   Grounded in the Kuro Signal Protocol palette (near-black ground,
   phosphor/circuit/spectre signals), reduced to the four hues that
   match Perlin Studio's existing brand (cyan / violet / green / near-
   black). System fonts only — no external CDN.
   ============================================================ */

:root {
  /* ----- Surfaces (the chamber) ----- */
  --bg:        #060709;  /* outermost — void-050 */
  --panel:     #0b0d11;  /* sidebar + main panel */
  --panel-2:   #11141a;  /* inset blocks, sub-sections */
  --panel-3:   #181c24;  /* hovered surfaces */

  /* ----- Borders ----- */
  --border:        #3a414c;  /* hairline, lifted for resting visibility */
  --border-strong: #474f5c;
  --border-input:  #343b45;
  --border-focus:  rgba(57, 255, 122, 0.55);

  /* ----- Foreground ----- */
  --text:      #e8e4d8;  /* pearl */
  --text-dim:  #828a97;
  --text-faint:#7e8694;  /* AA on panel-2 (>=4.5:1), still below text-dim */

  /* ----- Signals (brand-aligned) ----- */
  --accent:        #39ff7a;            /* phosphor / brand green */
  --accent-2:      #2bd965;            /* hover/press */
  --accent-text:   #39ff7a;            /* accent as small text (dark: same) */
  --accent-soft:   rgba(57,255,122,0.10);
  --accent-glow:   rgba(57,255,122,0.40);
  --accent-fg:     #06170c;            /* readable text on phosphor */

  --circuit:       #4ac8d8;            /* cyan / brand */
  --circuit-soft:  rgba(74,200,216,0.14);
  --spectre:       #a878ff;            /* violet / brand */
  --spectre-soft:  rgba(168,120,255,0.16);
  --danger:        #d4203a;            /* crimson */
  --danger-soft:   rgba(212,32,58,0.18);

  /* ----- System ----- */
  --radius:    10px;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-pill: 999px;
  --gap:       14px;
  --gap-sm:    8px;

  /* Type scale — consolidated from ad-hoc literals (<=0.5px snaps). The 16px
     touch-input size stays a literal: it's a functional iOS-zoom threshold,
     not a type-scale step. */
  --fs-2xs:  10px;
  --fs-xs:   10.5px;
  --fs-sm:   11px;
  --fs-md:   12px;
  --fs-base: 14px;
  --fs-xl:   17px;

  --font-sans: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
               "Inter", "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  --font-mono: ui-monospace, "SF Mono", "JetBrains Mono", "Cascadia Mono",
               Menlo, Consolas, monospace;

  --tracking-caps: 0.14em;
  --tracking-tight: -0.015em;

  --shadow-card: 0 1px 0 0 rgba(255,255,255,0.025) inset,
                 0 8px 24px -16px rgba(0,0,0,0.7);
  --glow-focus:  0 0 0 2px var(--border-focus);

  --dur: 140ms;
  --ease: cubic-bezier(0.2, 0.8, 0.2, 1);
}

/* Light tokens apply when (system is light AND user hasn't forced dark)
   OR when user has explicitly chosen light. The :not() lets an explicit
   override beat the media query on light systems. */
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) {
    --bg:        #f3f0e6;   /* bone */
    --panel:     #fbf9f3;
    --panel-2:   #ece8dc;
    --panel-3:   #e3decf;

    --border:        #bdb5a0;
    --border-strong: #a89e85;
    --border-input:  #c6bfac;
    --border-focus:  rgba(30, 160, 75, 0.55);

    --text:      #181c24;
    --text-dim:  #5a6170;
    --text-faint:#5f6670;

    /* Light-theme accent: darken phosphor for AA contrast on bone */
    --accent:      #1ea84a;
    --accent-2:    #157a36;
    --accent-text: #13702f;
    --accent-soft: rgba(30,168,74,0.10);
    --accent-glow: rgba(30,168,74,0.30);
    --accent-fg:   #ffffff;

    --circuit:     #117a87;
    --circuit-soft:rgba(17,122,135,0.14);
    --spectre:     #6e3acf;
    --spectre-soft:rgba(110,58,207,0.16);
    --danger:      #b8132c;
    --danger-soft: rgba(184,19,44,0.14);

    --shadow-card: 0 1px 0 0 rgba(255,255,255,0.6) inset,
                   0 8px 24px -16px rgba(20,15,5,0.18);
  }
}
:root[data-theme="light"] {
  --bg:        #f3f0e6;
  --panel:     #fbf9f3;
  --panel-2:   #ece8dc;
  --panel-3:   #e3decf;

  --border:        #bdb5a0;
  --border-strong: #a89e85;
  --border-input:  #c6bfac;
  --border-focus:  rgba(30, 160, 75, 0.55);

  --text:      #181c24;
  --text-dim:  #5a6170;
  --text-faint:#5f6670;

  --accent:      #1ea84a;
  --accent-2:    #157a36;
  --accent-text: #13702f;
  --accent-soft: rgba(30,168,74,0.10);
  --accent-glow: rgba(30,168,74,0.30);
  --accent-fg:   #ffffff;

  --circuit:     #117a87;
  --circuit-soft:rgba(17,122,135,0.14);
  --spectre:     #6e3acf;
  --spectre-soft:rgba(110,58,207,0.16);
  --danger:      #b8132c;
  --danger-soft: rgba(184,19,44,0.14);

  --shadow-card: 0 1px 0 0 rgba(255,255,255,0.6) inset,
                 0 8px 24px -16px rgba(20,15,5,0.18);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: var(--fs-base);
  line-height: 1.5;
  color-scheme: dark;
  accent-color: var(--accent);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
@media (prefers-color-scheme: light) {
  html:not([data-theme="dark"]), html:not([data-theme="dark"]) body { color-scheme: light; }
}
html[data-theme="light"], html[data-theme="light"] body { color-scheme: light; }
html[data-theme="dark"],  html[data-theme="dark"]  body { color-scheme: dark; }

/* ============================================================
   TOPBAR
   ============================================================ */
.topbar {
  position: relative;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 28px 14px;
  border-bottom: 1px solid var(--border);
}
/* Decorative <perlin-noise> behind the header, dimmed by a scrim so the
   brand and chips stay legible. The element handles reduced-motion (still
   frame) and pauses when off-screen on its own. */
.topbar-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  opacity: 0.35;
  pointer-events: none;
}
.topbar::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  background: var(--bg);
  opacity: 0.58;
  pointer-events: none;
}
.topbar > .brand,
.topbar > .topbar-meta,
.topbar > .theme-toggle {
  position: relative;
  z-index: 2;
}
.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: inherit;
  text-decoration: none;
}
.brand-mark {
  display: inline-flex;
  width: 32px; height: 32px;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 0 0 1px var(--border), 0 0 16px -4px rgba(168,120,255,0.35);
}
.brand-text { display: flex; flex-direction: column; gap: 1px; }
.brand-eyebrow {
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: var(--tracking-caps);
  color: var(--text-faint);
}
.brand-title {
  font-family: var(--font-sans);
  font-size: var(--fs-xl);
  font-weight: 600;
  letter-spacing: var(--tracking-tight);
  margin: 0;
  line-height: 1.1;
}
.topbar-meta {
  display: flex;
  align-items: center;
  gap: 6px;
  margin: 0;
}
.chip-mono {
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-dim);
  padding: 3px 8px;
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  background: var(--panel);
}
.chip-mono:nth-child(1) { color: var(--circuit); border-color: color-mix(in oklab, var(--circuit) 30%, var(--border)); }
.chip-mono:nth-child(2) { color: var(--accent-text); border-color: color-mix(in oklab, var(--accent) 30%, var(--border)); }
.chip-mono:nth-child(3) { color: var(--spectre); border-color: color-mix(in oklab, var(--spectre) 30%, var(--border)); }

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px; height: 30px;
  padding: 0;
  margin-left: 4px;
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  background: var(--panel);
  color: var(--text-dim);
  cursor: pointer;
  transition: color var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              background var(--dur) var(--ease);
}
.theme-toggle:hover {
  color: var(--accent-text);
  border-color: color-mix(in oklab, var(--accent) 35%, var(--border));
  background: var(--panel-3);
}
.theme-toggle:focus-visible {
  outline: none;
  box-shadow: var(--glow-focus);
}
.theme-icon { display: none; }
/* Default (dark): show sun = click to go light */
.theme-icon-sun { display: inline-block; }
/* System light & no forced dark: show moon = click to go dark */
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .theme-icon-sun  { display: none; }
  :root:not([data-theme="dark"]) .theme-icon-moon { display: inline-block; }
}
/* Explicit overrides — placed after the media query so they win on equal specificity */
:root[data-theme="dark"]  .theme-icon-sun  { display: inline-block; }
:root[data-theme="dark"]  .theme-icon-moon { display: none; }
:root[data-theme="light"] .theme-icon-sun  { display: none; }
:root[data-theme="light"] .theme-icon-moon { display: inline-block; }

@media (max-width: 720px) {
  .topbar { padding: 14px 16px 12px; flex-wrap: wrap; }
  .topbar-meta .chip-mono:nth-child(3) { display: none; }
}

/* ============================================================
   LAYOUT
   ============================================================ */
main {
  display: grid;
  grid-template-columns: minmax(280px, 340px) 1fr;
  gap: var(--gap);
  padding: var(--gap);
  align-items: start;
  max-width: 1680px;
  margin: 0 auto;
}
/* Tablet: tighter sidebar padding but still 2-col */
@media (max-width: 1100px) {
  main { grid-template-columns: minmax(260px, 300px) 1fr; gap: 10px; padding: 10px; }
  .sidebar { padding: 4px 14px 14px; }
  .ctrl-section { padding: 12px 0 14px; }
}
/* Mobile: stack, canvas first */
@media (max-width: 720px) {
  main { grid-template-columns: 1fr; }
  .main { order: -1; position: static !important; }
  /* Definite height so the canvas object-fit:contain has a box to fill. The
     #canvas-wrap id beats the later equal-specificity base .canvas-wrap rule,
     so this mobile sizing actually wins the cascade. */
  #canvas-wrap { height: 60vh; height: 60dvh; min-height: 280px; padding: 32px 14px 14px; }
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
}

/* ============================================================
   SIDEBAR
   ============================================================ */
.sidebar {
  padding: 6px 18px 18px;
}
.ctrl-section {
  padding: 14px 0 16px;
  border-bottom: 1px solid var(--border);
}
.ctrl-section:last-child { border-bottom: none; padding-bottom: 4px; }
.ctrl-section:first-child { padding-top: 12px; }

.ctrl-section h2 {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: var(--tracking-caps);
  color: var(--text);
}
.sec-num {
  color: var(--accent-text);
  font-weight: 700;
}
.sec-name {
  color: var(--text);
}
.ctrl-section h2::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--border);
  margin-left: 4px;
  align-self: center;
}
.sec-hint {
  margin: -4px 0 10px;
  font-size: var(--fs-sm);
  color: var(--text-faint);
  font-family: var(--font-mono);
  letter-spacing: 0.01em;
  line-height: 1.5;
}
/* A hint placed below controls (not under an h2) needs the gap above, not the
   tuck the default negative top-margin gives. */
.webm-mask-hint { margin: 8px 0 0; }

/* ----- Form rows ----- */
label {
  display: block;
  margin-bottom: 10px;
  font-size: var(--fs-sm);
  color: var(--text-dim);
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}
label .unit {
  color: var(--text-faint);
  font-size: var(--fs-2xs);
  margin-left: 4px;
}
/* Slider readout: caption + live value in a header row, slider below — same
   treatment as the transport t readout, so every range shows its value. */
.range-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px;
}
.range-val {
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  color: var(--accent-text);
  letter-spacing: 0.02em;
  font-variant-numeric: tabular-nums;
}
label.checkbox {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 0;
  cursor: pointer;
  color: var(--text);
  font-size: var(--fs-md);
}
label.checkbox input { margin: 0; }
.switch-row {
  padding: 8px 10px;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  margin-bottom: 10px;
}
.switch-label { color: var(--text); font-weight: 500; }
/* De-nest: inside a bordered color-section, drop the switch-row's own box. */
.color-section .switch-row {
  background: none;
  border: none;
  padding: 8px 0 0;
  margin-bottom: 0;
}
/* Progressive-disclosure wrappers (Layer 2 controls / Warp scale). */
.layer2-controls[hidden],
.warp-extra[hidden] { display: none; }

input[type="number"],
input[type="text"],
select,
textarea {
  width: 100%;
  margin-top: 4px;
  padding: 6px 9px;
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border-input);
  border-radius: var(--radius-md);
  font-size: var(--fs-md);
  font-family: var(--font-mono);
  letter-spacing: -0.01em;
  font-variant-numeric: tabular-nums;
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
input[type="number"]:hover,
select:hover {
  border-color: var(--border-strong);
}
input[type="number"]:focus,
input[type="text"]:focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: var(--glow-focus);
}

/* Number-input spinner padding */
input[type="number"] { padding-right: 4px; }

select {
  appearance: none;
  -webkit-appearance: none;
  background-image:
    linear-gradient(45deg, transparent 50%, var(--text-dim) 50%),
    linear-gradient(135deg, var(--text-dim) 50%, transparent 50%);
  background-position:
    right 12px top 50%,
    right 7px top 50%;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
  padding-right: 24px;
}

/* Custom checkbox */
input[type="checkbox"] {
  appearance: none;
  -webkit-appearance: none;
  width: 14px; height: 14px;
  border: 1px solid var(--border-strong);
  background: var(--panel-2);
  border-radius: 3px;
  cursor: pointer;
  display: inline-grid;
  place-content: center;
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
input[type="checkbox"]:checked {
  background: var(--accent);
  border-color: var(--accent);
}
input[type="checkbox"]:checked::after {
  content: "";
  width: 8px;
  height: 4px;
  border-left: 1.5px solid var(--accent-fg);
  border-bottom: 1.5px solid var(--accent-fg);
  transform: rotate(-45deg) translate(0.5px, -0.5px);
}
input[type="checkbox"]:focus-visible { box-shadow: var(--glow-focus); }

/* Range slider */
input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 22px;
  background: transparent;
  margin-top: 4px;
  cursor: pointer;
}
input[type="range"]::-webkit-slider-runnable-track {
  height: 3px;
  background: var(--border);
  border-radius: 2px;
}
input[type="range"]::-moz-range-track {
  height: 3px;
  background: var(--border);
  border-radius: 2px;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 14px; height: 14px;
  background: var(--text);
  border: 2px solid var(--bg);
  border-radius: 50%;
  margin-top: -6px;
  box-shadow: 0 0 0 1px var(--border-strong);
  transition: background var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
input[type="range"]::-moz-range-thumb {
  width: 14px; height: 14px;
  background: var(--text);
  border: 2px solid var(--bg);
  border-radius: 50%;
  box-shadow: 0 0 0 1px var(--border-strong);
}
input[type="range"]:hover::-webkit-slider-thumb { background: var(--accent); box-shadow: 0 0 0 1px var(--accent), 0 0 8px var(--accent-glow); }
input[type="range"]:hover::-moz-range-thumb { background: var(--accent); }
input[type="range"]:focus-visible::-webkit-slider-thumb { box-shadow: var(--glow-focus); }

/* Grids */
.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px 10px;
}
.grid-3 {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 6px 8px;
}
.grid-2 > label,
.grid-3 > label { margin-bottom: 0; }
.grid-2 > label.span2 { grid-column: span 2; }
.checkbox-row { margin-top: 12px; gap: 4px 8px; }
.checkbox-row label { font-size: var(--fs-xs); }
.checkbox-row label span { color: var(--text-dim); }

.select-row { margin-bottom: 8px; }

/* Always-visible entry point to the custom hex palette (otherwise two
   dropdowns deep). Accent-tinted so it reads as the way to your own colours. */
.custom-palette-cta {
  width: 100%;
  margin-bottom: 10px;
  color: var(--accent-text);
  background: var(--accent-soft);
  border-color: color-mix(in oklab, var(--accent) 40%, var(--border));
}
.custom-palette-cta:hover:not(:disabled) {
  color: var(--accent-text);
  background: color-mix(in oklab, var(--accent) 16%, var(--panel-2));
  border-color: var(--accent);
}

/* Color sub-sections */
.color-section {
  margin-top: 10px;
  padding: 12px;
  background: var(--panel-2);
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  position: relative;
}
.color-section[hidden] { display: none; }
.color-section > label { margin-bottom: 10px; }
.color-section > label:last-child { margin-bottom: 0; }

/* Gradient preview */
.gradient-preview-wrap { margin-top: 8px; }
.gradient-preview {
  height: 36px;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  background: linear-gradient(to right, #444, #aaa);  /* JS overwrites */
  box-shadow: inset 0 0 0 1px rgba(0,0,0,0.25);
}
.gradient-ticks {
  display: flex;
  justify-content: space-between;
  padding: 4px 2px 0;
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  color: var(--text-faint);
  letter-spacing: 0.04em;
}

/* Custom-gradient stops editor */
.custom-stops {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px solid var(--border);
}
.custom-stops[hidden] { display: none; }
.custom-stops-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 8px;
}
/* Paste-palette box */
.palette-label {
  display: block;
  margin-bottom: 4px;
  font-size: var(--fs-sm);
  color: var(--text-dim);
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}
.palette-input {
  resize: vertical;
  min-height: 38px;
  line-height: 1.4;
}
.apply-palette-btn {
  width: 100%;
  margin: 8px 0 12px;
  font-size: var(--fs-xs);
  color: var(--text-dim);
  background: var(--panel-3);
}
.apply-palette-btn:hover:not(:disabled) {
  color: var(--accent-text);
  border-color: color-mix(in oklab, var(--accent) 30%, var(--border));
}
.custom-stop {
  display: grid;
  grid-template-columns: 1fr auto auto auto auto;  /* pos | value | swatch | hex | remove */
  align-items: center;
  gap: 6px;
}
.custom-stop .stop-pos {
  width: 100%;
  margin: 0;
}
.custom-stop .stop-hex {
  width: 66px;
  margin: 0;
  padding: 4px 5px;
  font-size: var(--fs-2xs);
  text-align: center;
  text-transform: lowercase;
}
.custom-stop .stop-val {
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  color: var(--text-dim);
  font-variant-numeric: tabular-nums;
  min-width: 2.4em;
  text-align: right;
}
.custom-stop .stop-color {
  width: 28px; height: 26px;
  padding: 0;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  background: var(--panel-3);
  cursor: pointer;
}
.custom-stop .stop-color::-webkit-color-swatch-wrapper { padding: 2px; }
.custom-stop .stop-color::-webkit-color-swatch {
  border: none;
  border-radius: 2px;
}
.custom-stop .stop-color::-moz-color-swatch {
  border: none;
  border-radius: 2px;
}
.custom-stop .stop-remove {
  width: 24px; height: 24px;
  padding: 0;
  font-size: var(--fs-base);
  line-height: 1;
  color: var(--text-dim);
  background: var(--panel-3);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}
.custom-stop .stop-remove:hover:not(:disabled) {
  color: var(--danger);
  border-color: color-mix(in oklab, var(--danger) 30%, var(--border));
}
.custom-stop .stop-remove:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}
.add-stop-btn {
  width: 100%;
  padding: 6px 10px;
  font-size: var(--fs-xs);
  color: var(--text-dim);
  background: var(--panel-3);
}
.add-stop-btn:hover:not(:disabled) {
  color: var(--accent-text);
  border-color: color-mix(in oklab, var(--accent) 30%, var(--border));
}

/* Mask section */
.mask-controls {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.mask-controls > button {
  text-align: left;
}
.mask-controls .mask-name {
  margin: 2px 0;
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  color: var(--text-faint);
  letter-spacing: 0.02em;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
#btn-mask-load,
#btn-mask-clear {
  font-size: var(--fs-xs);
}
#btn-mask-load { width: 100%; }
#btn-mask-clear { width: 100%; }

/* ============================================================
   BUTTONS
   ============================================================ */
button {
  font: inherit;
  font-family: var(--font-mono);
  font-size: var(--fs-sm);
  letter-spacing: 0.04em;
  padding: 8px 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-strong);
  background: var(--panel-2);
  color: var(--text);
  cursor: pointer;
  transition: background var(--dur) var(--ease),
              border-color var(--dur) var(--ease),
              color var(--dur) var(--ease),
              transform 80ms var(--ease);
}
button:hover:not(:disabled) {
  background: var(--panel-3);
  border-color: var(--accent);
  color: var(--text);
}
button:active:not(:disabled) { transform: translateY(1px); }
button:focus-visible { outline: none; box-shadow: var(--glow-focus); }
button:disabled { opacity: 0.45; cursor: not-allowed; }

button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-fg);
  font-weight: 700;
  box-shadow: 0 0 16px -8px var(--accent-glow);
}
button.primary:hover:not(:disabled) {
  background: var(--accent-2);
  border-color: var(--accent-2);
  color: var(--accent-fg);
  box-shadow: 0 0 24px -6px var(--accent-glow);
}
/* Light theme: the white primary-button label needs a deeper green to reach
   AA (4.5:1); the dark theme's phosphor green is already high-contrast. The
   raised glow on hover still provides the hover cue. */
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) button.primary {
    background: var(--accent-2);
    border-color: var(--accent-2);
  }
}
:root[data-theme="light"] button.primary {
  background: var(--accent-2);
  border-color: var(--accent-2);
}

/* Preset action row */
.preset-actions, .export-actions {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}
.preset-actions button { flex: 1; }
.export-actions { flex-direction: column; gap: 6px; }
.export-actions button { width: 100%; }

/* Preset chip = swatch + label */
.preset-builtins {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
  margin-top: 10px;
}
.preset-chip {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 5px 8px 5px 5px;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  color: var(--text-dim);
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  letter-spacing: 0.03em;
  text-transform: uppercase;
  cursor: pointer;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.preset-chip .chip-swatch {
  flex-shrink: 0;
  width: 22px;
  height: 12px;
  border-radius: var(--radius-pill);
  background: var(--chip-grad, linear-gradient(90deg, var(--accent), var(--circuit)));
  box-shadow: inset 0 0 0 1px rgba(0,0,0,0.4);
}
.preset-chip .chip-label { display: inline-block; }
.preset-chip:hover {
  border-color: var(--accent);
  color: var(--text);
  background: var(--panel-3);
}

/* ============================================================
   MAIN OUTPUT
   ============================================================ */
.main {
  padding: 14px;
  position: sticky;
  top: var(--gap);
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.canvas-frame {
  position: relative;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  /* subtle inner vignette so a blank canvas reads as "framed" */
  box-shadow: inset 0 0 60px -20px rgba(0,0,0,0.75);
}
.canvas-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 28px 20px 20px;
  min-height: 240px;
  /* Fit the frame to the viewport without pushing the transport off-screen.
     dvh tracks mobile browser chrome; the vh line is a fallback. The 240px
     floor keeps short landscape screens (~600-680px tall) from overflowing. */
  height: calc(100vh - 320px);
  height: clamp(240px, calc(100dvh - 320px), 720px);
  max-height: 720px;
}


#canvas-output {
  /* Fill the frame so low-resolution renders scale up into crisp pixel
     blocks (the deliberate "Minecraft" look) instead of sitting tiny at
     their native size. object-fit: contain preserves the render's aspect
     ratio — matte bars show the framed .canvas-frame vignette. The outer
     .canvas-frame supplies the framing, so no per-image shadow/ring. */
  image-rendering: pixelated;
  image-rendering: crisp-edges;
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}
#anim-preview {
  display: none;
  width: 100%;
  height: 100%;
  object-fit: contain;
  /* Low-res recordings play back upscaled-crisp to match the live canvas. */
  image-rendering: pixelated;
}
#anim-preview.ready { display: block; }
#canvas-output.hidden { display: none; }

/* ----- Frame corner tags ----- */
.frame-tag {
  position: absolute;
  top: 8px;
  z-index: 2;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 8px;
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  font-weight: 600;
  letter-spacing: var(--tracking-caps);
  text-transform: uppercase;
  color: var(--text-dim);
  background: color-mix(in oklab, var(--panel) 70%, transparent);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}
.frame-tag-tl { left: 8px; }
.frame-tag-tr { right: 8px; }
/* The corner tag reflects the real transport state. */
.frame-tag-tr.is-live   { color: var(--accent-text); border-color: color-mix(in oklab, var(--accent) 35%, var(--border)); }
.frame-tag-tr.is-paused { color: var(--text-dim); border-color: var(--border); }
.frame-tag-tr.is-rec    { color: var(--danger); border-color: color-mix(in oklab, var(--danger) 45%, var(--border)); }
.tag-dot {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: currentColor;
  box-shadow: 0 0 6px currentColor;
}
.frame-tag-tr.is-live .tag-dot { animation: dot-pulse 2s ease-in-out infinite; }
.frame-tag-tr.is-rec  .tag-dot { animation: dot-pulse 1s ease-in-out infinite; }
@keyframes dot-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

/* First-paint loading indicator, cleared on the first rendered frame. */
.canvas-loading {
  position: absolute;
  inset: 0;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: var(--fs-sm);
  letter-spacing: var(--tracking-caps);
  text-transform: uppercase;
  color: var(--text-faint);
  pointer-events: none;
  animation: loading-pulse 1.2s ease-in-out infinite;
}
.canvas-loading[hidden] { display: none; }
@keyframes loading-pulse {
  0%, 100% { opacity: 0.35; }
  50% { opacity: 0.85; }
}

/* ============================================================
   TRANSPORT BAR
   ============================================================ */
.transport {
  display: grid;
  grid-template-columns: auto auto 1fr;
  gap: 10px;
  align-items: end;
  padding: 12px 14px;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.transport-btn {
  font-family: var(--font-mono);
  font-size: var(--fs-base);
  padding: 8px 14px;
  min-width: 44px;
  height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.transport-btn .play-glyph { line-height: 1; }
/* Play reflects transport state: filled accent while running, neutral idle. */
#btn-play.is-playing {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-fg);
}
#btn-play.is-playing:hover:not(:disabled) {
  background: var(--accent-2);
  border-color: var(--accent-2);
  color: var(--accent-fg);
}
/* Light theme: the white glyph needs the deeper green to pass AA (mirrors
   button.primary). */
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) #btn-play.is-playing { background: var(--accent-2); border-color: var(--accent-2); }
}
:root[data-theme="light"] #btn-play.is-playing { background: var(--accent-2); border-color: var(--accent-2); }

.t-slider {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin: 0;
  min-width: 0;
}
.t-label {
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  color: var(--text-faint);
  text-transform: uppercase;
  letter-spacing: var(--tracking-caps);
}
.t-label-name { color: var(--text-dim); }
.t-label-eq { color: var(--text-faint); }
.t-label-val { color: var(--accent-text); font-weight: 600; letter-spacing: 0.02em; text-transform: none; }
.t-slider input[type="range"] { margin: 0; height: 18px; }

@media (max-width: 720px) {
  .transport {
    grid-template-columns: auto auto 1fr;
    grid-template-rows: auto auto;
    row-gap: 10px;
  }
  .t-slider { grid-column: 1 / -1; grid-row: 2; }
  .transport-btn { grid-row: 1; }
}

/* ============================================================
   STATUS + FPS + PROGRESS
   ============================================================ */
.status-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 0 4px;
  min-height: 18px;
}
.status {
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  letter-spacing: 0.04em;
  color: var(--text-faint);
  flex: 1;
  text-transform: uppercase;
}
.status::before {
  content: ">";
  color: var(--accent-text);
  margin-right: 6px;
  opacity: 0.7;
}
.status.error {
  color: var(--danger);
}
.status.error::before {
  content: "!";
  color: var(--danger);
}
.fps-counter {
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  color: var(--circuit);
  letter-spacing: 0.04em;
  padding: 2px 8px;
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  background: var(--panel-2);
  min-height: 18px;
  min-width: 0;
}
.fps-counter:empty { display: none; }
.engine-mode {
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  letter-spacing: var(--tracking-caps);
  text-transform: uppercase;
  color: var(--danger);
  border: 1px solid color-mix(in oklab, var(--danger) 40%, var(--border));
  border-radius: var(--radius-pill);
  padding: 1px 7px;
  background: var(--danger-soft);
}
.engine-mode[hidden] { display: none; }

.progress {
  height: 3px;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 2px;
  overflow: hidden;
  display: none;
}
.progress.active { display: block; }
.progress .bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--circuit));
  transition: width 80ms linear;
}

/* ============================================================
   FOOTER
   ============================================================ */
.bottombar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 14px 28px;
  border-top: 1px solid var(--border);
  margin-top: 8px;
}
.bottombar small {
  font-size: var(--fs-sm);
  color: var(--text-faint);
  display: inline-flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}
.bottombar .sep { color: var(--text-faint); opacity: 0.5; }
.foot-mono {
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  text-transform: uppercase;
  letter-spacing: var(--tracking-caps);
  color: var(--circuit);
  padding: 2px 7px;
  border: 1px solid color-mix(in oklab, var(--circuit) 30%, var(--border));
  border-radius: var(--radius-pill);
}
.bottombar code {
  font-family: var(--font-mono);
  font-size: var(--fs-xs);
  background: var(--panel-2);
  padding: 1px 5px;
  border-radius: 3px;
  color: var(--text);
  border: 1px solid var(--border);
}
.kbd {
  font-family: var(--font-mono);
  font-size: var(--fs-2xs);
  font-weight: 600;
  padding: 2px 7px;
  background: var(--panel-2);
  border: 1px solid var(--border-strong);
  border-radius: 4px;
  color: var(--text);
  box-shadow: 0 1px 0 var(--border-strong);
}
.foot-dim { color: var(--text-faint); font-family: var(--font-mono); font-size: var(--fs-2xs); letter-spacing: 0.04em; }

@media (max-width: 720px) {
  .bottombar { flex-direction: column; align-items: flex-start; padding: 12px 16px; }
}

/* ============================================================
   TOUCH / COARSE POINTER
   Larger hit targets (WCAG 2.5.8) and a 16px input font so iOS Safari
   doesn't zoom-and-stick on focus. Desktop pixel metrics are untouched.
   ============================================================ */
@media (pointer: coarse) {
  input[type="number"],
  input[type="text"],
  select { font-size: 16px; }

  input[type="range"],
  .t-slider input[type="range"] { height: 28px; }
  input[type="range"]::-webkit-slider-thumb { width: 24px; height: 24px; margin-top: -11px; }
  input[type="range"]::-moz-range-thumb { width: 24px; height: 24px; }

  label.checkbox { min-height: 24px; }
}

/* ============================================================
   REDUCED MOTION
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  .tag-dot { animation: none !important; }
  .canvas-loading { animation: none !important; }
  * { transition-duration: 0ms !important; }
}