/* Embedded hardware UI demos in project writeups.

   Demo shell contract (keep every live demo on this path):
   - Mount via figure.hardware-demo[data-demo] + .hardware-demo-frame
   - Optional data-fallback-* for static hardware when import/canvas fails
   - Figcaption carries data-hint-touch / data-hint-pointer; mount applies one
   - Frame role is "group" with aria-describedby pointing at the figcaption
   - Modules return { pause, resume } for offscreen/visibility lifecycle
   - Prefer aria-live for meaningful state changes (VSWR, UART, schedulability)
   - Prefer reduced-motion static/stepped paths over continuous animation
   - Site chrome tokens for shared controls; Montserrat/Kirby colors stay device-scoped
*/

/* Self-hosted Montserrat (Latin subset, variable woff2 covering 400-600).
   Used only by the companion (Kirby) demo, including its <canvas> UI. Path is
   relative to this file in css/. */
@font-face {
  font-family: "Montserrat";
  font-style: normal;
  font-weight: 400 600;
  font-display: swap;
  src: url("../assets/fonts/montserrat-latin.woff2") format("woff2");
}

.hardware-demo {
  grid-column: 2;
  margin: clamp(20px, 3vw, 28px) 0 0;
}

.hardware-demo-frame {
  position: relative;
  line-height: 0;
  outline: none;
}

.hardware-demo-frame:focus-visible {
  outline: 2px solid var(--accent-blue);
  outline-offset: 2px;
}

/* Demo error state (mirrors resume-viewer-status pattern). */
.hardware-demo-error {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-6);
  min-height: 120px;
  padding: var(--space-16) var(--space-8);
  text-align: center;
  line-height: 1.4;
}

.hardware-demo-error-msg {
  margin: 0;
  color: var(--ink-mute);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .04em;
}

.hardware-demo-error-action {
  appearance: none;
  display: inline;
  border: none;
  background: none;
  padding: 0;
  color: var(--ink-soft);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .04em;
  text-decoration: underline;
  text-underline-offset: 3px;
  cursor: pointer;
  transition: color var(--dur-fast) var(--ease);
}

.hardware-demo-error-action:hover {
  color: var(--ink);
}

.hardware-demo-error-action:focus-visible {
  outline: 2px solid var(--accent-blue);
  outline-offset: 2px;
}

/* Demo loading skeleton (shown while the demo module imports). */
.hardware-demo-skeleton {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  min-height: clamp(160px, 30vw, 240px);
  background: color-mix(in oklch, var(--bone) 82%, transparent);
  overflow: hidden;
}

.hardware-demo-skeleton-label {
  position: relative;
  z-index: 1;
  color: var(--ink-mute);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.hardware-demo-skeleton::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(
    90deg,
    transparent 0%,
    color-mix(in oklch, var(--ink) 7%, transparent) 50%,
    transparent 100%
  );
  transform: translateX(-100%);
  animation: hardware-demo-shimmer 1.4s var(--ease) infinite;
}

@keyframes hardware-demo-shimmer {
  to {
    transform: translateX(100%);
  }
}

@media (prefers-reduced-motion: reduce) {
  .hardware-demo-skeleton::after {
    animation: none;
  }
}

/* Per-demo skeleton sizing to minimise layout shift on settle. */
.hardware-demo--impedance .hardware-demo-skeleton {
  width: min(1056px, 100%);
  min-height: 0;
  aspect-ratio: 132 / 68;
}

.hardware-demo--companion .hardware-demo-skeleton {
  position: absolute;
  inset: 0;
  min-height: 0;
}

.hardware-demo--heatmap .hardware-demo-skeleton {
  aspect-ratio: 1;
  min-height: 0;
  width: min(320px, 100%);
}

.hardware-demo--vehicle .hardware-demo-skeleton {
  min-height: clamp(280px, 42vw, 360px);
}

.hardware-demo--robot .hardware-demo-skeleton {
  min-height: clamp(280px, 44vw, 380px);
}

.hardware-demo--keychain .hardware-demo-skeleton {
  min-height: clamp(220px, 36vw, 300px);
}

.hardware-demo--impedance {
  width: fit-content;
  max-width: 100%;
}

.hardware-demo--impedance canvas {
  display: block;
  width: min(1056px, 100%);
  height: auto;
  aspect-ratio: 132 / 68;
  background: #000;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
  /* none (not manipulation) so vertical drags scroll the on-screen menu
     instead of panning the page -- the demo handles the gesture itself. */
  touch-action: none;
  cursor: pointer;
}

.hardware-demo--companion {
  width: min(640px, 100%);
  max-width: 100%;
}

.hardware-demo--companion .hardware-demo-frame {
  container-type: inline-size;
  width: 100%;
  aspect-ratio: 4 / 3;
  overflow: hidden;
}

.hardware-demo--companion figcaption {
  box-sizing: border-box;
}

.hardware-demo--companion .kirby-viewport {
  display: block;
  width: 320px;
  height: 240px;
  transform-origin: top left;
  transform: scale(calc(100cqw / 320px));
  image-rendering: pixelated;
  image-rendering: crisp-edges;
}

.hardware-demo figcaption {
  margin: var(--space-5) 0 0;
  padding: var(--space-5) var(--space-7) var(--space-6);
  border: 1px solid var(--rule-light);
  border-radius: var(--radius-sm);
  background: color-mix(in oklch, var(--bone) 88%, transparent);
  color: var(--ink-mute);
  font-size: 11px;
  letter-spacing: .08em;
  text-transform: uppercase;
}

@media (prefers-reduced-motion: reduce) {
  .kirby-viewport *,
  .kirby-slide-enter,
  .kirby-slide-exit {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

/* Kirby demo viewport internals (320×240 logical). */
.kirby-viewport {
  position: relative;
  width: 320px;
  height: 240px;
  overflow: hidden;
  touch-action: none;
  user-select: none;
  font-family: Montserrat, sans-serif;
}

.kirby-track {
  display: flex;
  width: 1280px;
  height: 240px;
  will-change: transform;
}

.kirby-slide {
  flex: 0 0 320px;
  width: 320px;
  height: 240px;
  position: relative;
}

.kirby-screen {
  position: absolute;
  inset: 0;
  width: 320px;
  height: 240px;
  overflow: hidden;
}

.kirby-subscreen {
  position: absolute;
  inset: 0;
}

.kirby-hidden {
  display: none !important;
}

.kirby-label {
  position: absolute;
  margin: 0;
  white-space: nowrap;
  pointer-events: none;
  line-height: 1.2;
}

.kirby-label--mid {
  line-height: 1;
}

.kirby-btn {
  position: absolute;
  border: 2px solid color-mix(in srgb, white 50%, transparent);
  border-radius: 999px;
  color: rgb(255, 245, 235);
  font-family: Montserrat, sans-serif;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 4px 14px color-mix(in srgb, black 50%, transparent);
}

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

.kirby-btn:active {
  transform: translateY(1px);
  box-shadow: 0 1px 4px color-mix(in srgb, black 50%, transparent);
}

.kirby-roller {
  position: absolute;
  width: 66px;
  height: 92px;
  overflow: hidden;
  border: 2px solid color-mix(in srgb, rgb(210, 170, 255) 50%, transparent);
  border-radius: 14px;
  background: linear-gradient(180deg, rgb(58, 44, 104), rgb(45, 34, 86));
}

.kirby-roller--sm {
  width: 72px;
  height: 96px;
}

.kirby-roller-list {
  height: 100%;
  overflow-y: auto;
  scrollbar-width: none;
}

.kirby-roller-list::-webkit-scrollbar {
  display: none;
}

.kirby-roller-item {
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 0;
  background: transparent;
  width: 100%;
  padding: 0;
  font: inherit;
  font-size: 16px;
  font-weight: 600;
  color: rgb(175, 165, 200);
  cursor: pointer;
}

.kirby-roller-item.selected {
  color: rgb(255, 250, 245);
  background: color-mix(in srgb, rgb(255, 150, 210) 50%, transparent);
  font-size: 20px;
}

.kirby-roller-item:focus-visible {
  outline: 2px solid var(--accent-blue);
  outline-offset: -2px;
}

.kirby-sep {
  position: absolute;
  left: 18px;
  width: 284px;
  height: 1px;
  background: color-mix(in srgb, white 20%, transparent);
}

.kirby-tmr-rollers {
  position: absolute;
  left: 0;
  top: 18px;
  width: 320px;
  height: 120px;
}

.kirby-game-canvas {
  position: absolute;
  inset: 0;
  width: 320px;
  height: 240px;
  touch-action: none;
}

.kirby-game-overlay {
  position: absolute;
  inset: 0;
  z-index: 2;
}

.kirby-screen > .kirby-btn {
  z-index: 3;
}

.kirby-mute-toggle {
  position: absolute;
  right: 8px;
  bottom: 8px;
  z-index: 12;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  min-width: 44px;
  min-height: 44px;
  padding: 8px 12px;
  border: 2px solid color-mix(in srgb, white 40%, transparent);
  border-radius: 999px;
  background: color-mix(in srgb, rgb(20, 15, 40) 88%, transparent);
  color: rgb(255, 245, 235);
  font-family: Montserrat, sans-serif;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  line-height: 1;
  cursor: pointer;
  touch-action: manipulation;
  -webkit-tap-highlight-color: var(--tap-highlight);
  box-shadow: 0 4px 14px color-mix(in srgb, black 45%, transparent);
}

.kirby-mute-icon {
  width: 20px;
  height: 20px;
  flex: 0 0 auto;
}

.kirby-mute-icon--on {
  display: none;
}

.kirby-mute-icon--off {
  display: block;
}

.kirby-mute-toggle.is-on .kirby-mute-icon--on {
  display: block;
}

.kirby-mute-toggle.is-on .kirby-mute-icon--off {
  display: none;
}

.kirby-mute-label {
  display: none;
}

.kirby-mute-toggle:not(.is-on) {
  opacity: 0.82;
}

.kirby-mute-toggle:active {
  transform: translateY(1px);
  box-shadow: 0 1px 4px color-mix(in srgb, black 45%, transparent);
}

@media (hover: none) and (pointer: coarse) {
  .kirby-mute-toggle {
    min-width: 48px;
    min-height: 48px;
    padding: 10px 14px;
  }

  .kirby-mute-label {
    display: inline;
  }

  .kirby-mute-icon {
    width: 22px;
    height: 22px;
  }
}

@media (max-width: 900px) {
  .writeup-section .hardware-demo {
    grid-column: 1;
  }
}

:root {
  --rtos-pid: var(--brand-light);
  --rtos-uart: var(--olive);
  --rtos-lcd: var(--stone);
  --rtos-idle: var(--rule-light);
  --rtos-pendsv: var(--ink-mute);
  --rtos-miss: #b3392c;
}

:root[data-theme="dark"] {
  --rtos-miss: #e0665a;
}

:root {
  --robot-body: var(--brand);
  --robot-accent: var(--brand-light);
  --robot-bottle: #4f8a5b;
  --robot-bottle-cap: #345e3d;
  --robot-detect: var(--rtos-miss);
  --robot-scan: var(--ink-faint);
}

:root[data-theme="dark"] {
  --robot-bottle: #6fae7b;
  --robot-bottle-cap: #4a7d55;
}

/* RTOS scheduler demo (vehicle project). */
.hardware-demo--vehicle {
  width: min(620px, 100%);
  max-width: 100%;
}

.hardware-demo--vehicle .hardware-demo-frame {
  border: 1px solid var(--rule-light);
  border-radius: var(--radius);
  background: var(--surface);
  padding: clamp(12px, 2vw, 18px);
}

.rtos-demo {
  display: flex;
  flex-direction: column;
  gap: var(--space-8);
}

.rtos-canvas-wrap {
  width: 100%;
  max-width: 620px;
  line-height: 0;
}

.rtos-canvas-wrap canvas {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius-sm);
}

.rtos-controls {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
}

.rtos-rows {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.rtos-row {
  display: grid;
  grid-template-columns: 56px 1fr 1fr;
  align-items: center;
  gap: 10px;
  padding: var(--space-4) 10px;
  border-radius: var(--radius-sm);
  background: color-mix(in oklch, var(--rtos-row-color, var(--rule)) 10%, transparent);
}

.rtos-row-swatch {
  display: inline-block;
  width: 10px;
  height: 10px;
  margin-right: var(--space-4);
  border-radius: var(--radius-sm);
  background: var(--rtos-row-color, var(--rule));
  vertical-align: middle;
}

.rtos-row-name {
  font-size: 11px;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--ink);
}

.rtos-field {
  display: flex;
  align-items: center;
  gap: var(--space-7);
}

.rtos-field-label {
  font-size: 10px;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--ink-mute);
  width: 10px;
  padding-left: var(--space-4);
}

.rtos-stepper {
  display: inline-flex;
  align-items: center;
  border: 1px solid var(--rule-light);
  border-radius: var(--radius-sm);
  overflow: hidden;
  background: var(--bg);
}

.rtos-stepper:focus-within {
  outline: 2px solid var(--accent-blue);
  outline-offset: 2px;
}

.rtos-stepper-btn {
  appearance: none;
  border: none;
  background: transparent;
  color: var(--ink-soft);
  min-width: 44px;
  min-height: 44px;
  width: 44px;
  height: 44px;
  font-size: 14px;
  line-height: 1;
  cursor: pointer;
  touch-action: manipulation;
  transition: background var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}

.rtos-stepper-btn:focus-visible {
  outline: 2px solid var(--accent-blue);
  outline-offset: -2px;
  z-index: 1;
}

.rtos-stepper-btn:active:not(:disabled) {
  transform: translateY(1px);
}

.rtos-stepper-btn:disabled {
  color: var(--ink-faint);
  cursor: not-allowed;
  opacity: .45;
}

.rtos-stepper-input {
  appearance: textfield;
  width: 46px;
  min-width: 3.5ch;
  border: none;
  border-left: 1px solid var(--rule-light);
  border-right: 1px solid var(--rule-light);
  background: transparent;
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 12px;
  text-align: center;
  padding: var(--space-2) var(--space-4);
}

.rtos-stepper-input::-webkit-outer-spin-button,
.rtos-stepper-input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.rtos-stats {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4) var(--space-8);
  font-size: 11px;
  letter-spacing: .04em;
  color: var(--ink-mute);
}

.rtos-state {
  font-weight: 500;
  color: var(--brand);
}

.rtos-state.is-bad {
  color: var(--rtos-miss);
}

@media (max-width: 560px) {
  .rtos-row {
    display: flex;
    flex-wrap: wrap;
    row-gap: 6px;
  }

  .rtos-row-name {
    flex: 0 0 100%;
  }

  .rtos-field {
    flex: 1 1 0;
    min-width: 0;
  }

  .rtos-stepper {
    display: flex;
    width: 100%;
  }

  .rtos-stepper-input {
    flex: 1 1 0;
    width: auto;
    min-width: 3.5ch;
  }
}

/* Robot CV / UART pipeline demo. */
.hardware-demo--robot {
  width: min(760px, 100%);
  max-width: 100%;
}

.hardware-demo--robot .hardware-demo-frame {
  border: 1px solid var(--rule-light);
  border-radius: var(--radius);
  background: var(--surface);
  padding: clamp(12px, 2vw, 18px);
}

.robot-demo {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-8);
}

.robot-canvas-wrap {
  flex: 1 1 320px;
  min-width: 240px;
  max-width: 480px;
  line-height: 0;
  border-radius: var(--radius-sm);
  overflow: hidden;
  cursor: crosshair;
}

.robot-canvas-wrap canvas {
  display: block;
  width: 100%;
  height: auto;
  background: var(--bg);
}

.robot-side {
  flex: 1 1 220px;
  min-width: 200px;
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
}

.robot-stats {
  font-size: 11px;
  letter-spacing: .05em;
  text-transform: uppercase;
  color: var(--ink-mute);
}

.robot-log {
  border: 1px solid var(--rule-light);
  border-radius: var(--radius-sm);
  background: var(--bg);
  padding: var(--space-5) var(--space-6);
  flex: 1 1 auto;
  min-height: 180px;
  display: flex;
  flex-direction: column;
}

.robot-log-heading {
  font-size: 10px;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--ink-mute);
  margin-bottom: 8px;
}

.robot-log-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 5px;
  font-size: 11px;
  overflow-y: auto;
}

.robot-log-list li {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  padding: 3px 0;
  border-bottom: 1px dashed var(--rule-light);
}

.robot-log-list li:last-child {
  border-bottom: none;
}

.robot-log-hex {
  color: var(--ink-faint);
  white-space: nowrap;
}

.robot-log-label {
  color: var(--ink);
  font-weight: 500;
  white-space: nowrap;
}

.robot-controls {
  flex: 1 1 100%;
  order: 3;
  display: flex;
  align-items: center;
  gap: var(--space-5);
}

.robot-btn {
  appearance: none;
  min-height: 44px;
  min-width: 88px;
  padding: var(--space-4) var(--space-7);
  border: 1px solid var(--rule);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--ink);
  font: inherit;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  text-transform: uppercase;
  cursor: pointer;
  touch-action: manipulation;
  transition: background var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}

.robot-btn:active {
  transform: translateY(1px);
}

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

@media (hover: hover) and (pointer: fine) {
  .robot-btn:hover {
    background: var(--sand);
    border-color: var(--rule);
  }
}

@media (max-width: 640px) {
  .robot-demo {
    flex-direction: column;
  }

  .robot-canvas-wrap {
    flex: 0 0 auto;
    max-width: 100%;
  }

  .robot-side {
    flex: 0 0 auto;
  }
}

/* VSWR convergence heatmap (Impedance page companion demo). */
.impedance-demo-row {
  grid-column: 2;
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: clamp(16px, 2.5vw, 28px);
  margin: clamp(20px, 3vw, 28px) 0 0;
}

.impedance-demo-row .hardware-demo--impedance {
  flex: 2 1 560px;
  margin: 0;
}

.hardware-demo--heatmap {
  flex: 1 1 260px;
  min-width: 220px;
  max-width: 320px;
  margin: 0;
}

.hardware-demo--heatmap .hardware-demo-frame {
  border: 1px solid var(--rule);
  border-radius: var(--radius-sm);
  overflow: hidden;
  line-height: 0;
}

.hardware-demo--heatmap canvas {
  display: block;
  width: 100%;
  height: auto;
}

/* Keychain 555 / CD4017 LED chase visualizer. */
.hardware-demo--keychain {
  width: min(520px, 100%);
  max-width: 100%;
}

.hardware-demo--keychain .hardware-demo-frame {
  border: 1px solid var(--rule-light);
  border-radius: var(--radius);
  background: var(--surface);
  padding: clamp(12px, 2vw, 18px);
}

.keychain-demo {
  display: flex;
  flex-direction: column;
  gap: var(--space-8);
}

.keychain-stage {
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  padding: var(--space-8);
  border: 1px solid var(--rule-light);
  border-radius: var(--radius-sm);
  background: var(--bg);
}

.keychain-stage-label {
  color: var(--ink-mute);
  font-size: 10px;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.keychain-led-row {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: var(--space-5);
}

.keychain-led-cell {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-4);
}

.keychain-led {
  display: block;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 1px solid var(--rule);
  background: color-mix(in oklch, var(--stone) 28%, transparent);
  box-shadow: inset 0 0 0 1px color-mix(in oklch, var(--bg) 55%, transparent);
  transition: background var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), box-shadow var(--dur-fast) var(--ease);
}

.keychain-led.is-on {
  background: var(--brand-light);
  border-color: var(--brand);
  box-shadow:
    0 0 0 1px color-mix(in oklch, var(--brand-light) 35%, transparent),
    inset 0 0 0 1px color-mix(in oklch, var(--bone) 35%, transparent);
}

.keychain-led-tag {
  color: var(--ink-mute);
  font-size: 10px;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.keychain-path {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: stretch;
  gap: var(--space-4);
}

.keychain-path-arrow {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--ink-mute);
  font-size: 12px;
  line-height: 1;
  padding: 0 var(--space-1);
}

.keychain-chip {
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  gap: var(--space-2);
  min-width: 0;
  padding: var(--space-5) var(--space-6);
  border: 1px solid var(--rule-light);
  border-radius: var(--radius-sm);
  background: color-mix(in oklch, var(--bg) 70%, transparent);
  transition: border-color var(--dur-fast) var(--ease), background var(--dur-fast) var(--ease);
}

.keychain-chip.is-armed {
  border-color: var(--rule);
}

.keychain-chip.is-active {
  border-color: var(--brand-light);
  background: color-mix(in oklch, var(--brand-light) 12%, var(--surface));
}

.keychain-chip-role {
  color: var(--ink);
  font-size: 13px;
  line-height: 1.2;
  letter-spacing: -.01em;
}

.keychain-chip-part {
  color: var(--ink-mute);
  font-size: 10px;
  letter-spacing: .06em;
  text-transform: uppercase;
}

.keychain-chip-live {
  margin-top: var(--space-1);
  color: var(--brand);
  font-size: 11px;
  letter-spacing: .04em;
  text-transform: uppercase;
  font-variant-numeric: tabular-nums;
}

.keychain-chip:not(.is-armed) .keychain-chip-live {
  color: var(--ink-mute);
}

.keychain-chip .keychain-chip-explain {
  margin: var(--space-2) 0 0;
  max-width: none;
  color: var(--ink-mute);
  font-family: var(--font-body);
  font-size: 11px;
  line-height: 1.4;
  letter-spacing: 0;
  text-transform: none;
  min-height: 2.8em;
}

.keychain-controls {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-6);
  padding-top: var(--space-7);
  border-top: 1px solid var(--rule-light);
}

.keychain-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-5) var(--space-7);
  min-width: 0;
}

.keychain-status {
  color: var(--brand);
  font-size: 11px;
  letter-spacing: .06em;
  text-transform: uppercase;
  font-weight: 500;
}

.keychain-loop-meter {
  display: inline-flex;
  align-items: center;
  gap: 3px;
}

.keychain-loop-tick {
  display: block;
  width: 8px;
  height: 12px;
  border-radius: 1px;
  background: color-mix(in oklch, var(--stone) 30%, transparent);
  transition: background var(--dur-fast) var(--ease);
}

.keychain-loop-tick.is-on {
  background: var(--brand-light);
}

.keychain-loop-readout {
  color: var(--ink-mute);
  font-size: 11px;
  letter-spacing: .04em;
  font-variant-numeric: tabular-nums;
}

.keychain-press {
  appearance: none;
  min-height: 44px;
  min-width: 88px;
  padding: var(--space-4) var(--space-7);
  border: 1px solid var(--rule);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--ink);
  font: inherit;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  text-transform: uppercase;
  cursor: pointer;
  touch-action: manipulation;
  transition: background var(--dur-fast) var(--ease), border-color var(--dur-fast) var(--ease), color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}

.keychain-press:active:not(:disabled) {
  transform: translateY(1px);
}

.keychain-press:disabled {
  color: var(--ink-faint);
  border-color: var(--rule-light);
  cursor: not-allowed;
  opacity: .7;
}

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

@media (hover: hover) and (pointer: fine) {
  .keychain-press:hover:not(:disabled) {
    background: var(--sand);
    border-color: var(--rule);
    color: var(--ink);
  }
}

@media (max-width: 560px) {
  .keychain-led {
    width: 24px;
    height: 24px;
  }

  .keychain-path {
    grid-template-columns: 1fr;
    gap: var(--space-3);
  }

  .keychain-path-arrow {
    justify-content: center;
    padding: 0;
    width: 100%;
    font-size: 14px;
    transform: rotate(90deg);
  }

  .keychain-chip {
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: baseline;
    column-gap: var(--space-6);
    row-gap: var(--space-1);
  }

  .keychain-chip-role {
    grid-column: 1;
    grid-row: 1;
  }

  .keychain-chip-live {
    grid-column: 2;
    grid-row: 1;
    margin-top: 0;
    text-align: right;
    justify-self: end;
  }

  .keychain-chip-part {
    grid-column: 1;
    grid-row: 2;
  }

  .keychain-chip .keychain-chip-explain {
    grid-column: 1 / -1;
    grid-row: 3;
    min-height: 0;
  }

  .keychain-controls {
    align-items: stretch;
  }

  .keychain-press {
    width: 100%;
  }
}

@media (max-width: 900px) {
  .writeup-section .hardware-demo--keychain {
    grid-column: 1;
  }
}