:root {
  color-scheme: dark;
  --bg: #061014;
  --panel: rgba(8, 23, 30, 0.86);
  --panel-strong: rgba(10, 30, 38, 0.95);
  --line: #38dff0;
  --sample: #ffd166;
  --quant: #75f09a;
  --code: #c7a1ff;
  --alert: #ff5c78;
  --text: #f1fbff;
  --muted: #a8c0c7;
  --border: rgba(165, 238, 255, 0.24);
  --shadow: rgba(56, 223, 240, 0.24);
  --roll-duration: 260ms;
  --fast-roll-duration: 720ms;
  --division-shift-duration: 1180ms;
}

* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

html,
body {
  width: 100%;
  height: 100%;
  margin: 0;
  overflow: hidden;
  background: var(--bg);
  color: var(--text);
  font-family: "Yu Gothic", "Hiragino Kaku Gothic ProN", Meiryo, system-ui, sans-serif;
}

body.mobile-replica-host {
  position: fixed;
  inset: 0;
  background: #020609;
  overscroll-behavior: none;
  touch-action: manipulation;
  -webkit-user-select: none;
  user-select: none;
}

.mobile-replica-host > :not(.mobile-replica-frame):not(.mobile-landscape-gate) {
  display: none !important;
}

.mobile-landscape-gate {
  position: fixed;
  inset: 0;
  z-index: 110;
  display: grid;
  grid-template-rows: auto auto;
  place-content: center;
  gap: 8px;
  color: var(--text);
  background: var(--bg);
  text-align: center;
}

.mobile-landscape-gate strong {
  color: var(--line);
  font-size: 64px;
  line-height: 1;
}

.mobile-landscape-gate span {
  color: var(--text);
  font-size: 20px;
  font-weight: 1000;
}

.mobile-replica-frame {
  position: absolute;
  z-index: 100;
  width: 1366px;
  height: 768px;
  border: 0;
  background: var(--bg);
  transform-origin: left top;
  touch-action: manipulation;
}

body.mobile-replica-content {
  touch-action: manipulation;
  overscroll-behavior: none;
}

.mobile-replica-content .badge,
.mobile-replica-content .division-controls,
.mobile-replica-content .control-bar {
  -webkit-backdrop-filter: none;
  backdrop-filter: none;
}

button,
input,
output {
  font: inherit;
}

button {
  border: 0;
}

#stage {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  display: block;
}

.start-overlay {
  position: fixed;
  inset: 0;
  z-index: 30;
  display: grid;
  place-items: center;
  padding: 28px;
  background:
    linear-gradient(140deg, rgba(3, 8, 12, 0.96), rgba(8, 26, 31, 0.9)),
    repeating-linear-gradient(90deg, rgba(255, 255, 255, 0.03) 0 1px, transparent 1px 42px);
  transition: opacity 420ms ease, visibility 420ms ease;
}

.start-overlay.is-hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.start-panel {
  width: min(780px, 92vw);
  padding: 34px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: linear-gradient(160deg, rgba(8, 24, 31, 0.96), rgba(18, 18, 34, 0.92));
  box-shadow: 0 0 42px var(--shadow), inset 0 0 28px rgba(255, 255, 255, 0.035);
  text-align: center;
}

.start-kicker {
  margin-bottom: 12px;
  color: var(--sample);
  font-size: 18px;
  font-weight: 900;
  letter-spacing: 0;
}

.start-panel h1 {
  margin: 0;
  font-size: clamp(34px, 5.7vw, 58px);
  line-height: 1.14;
}

.start-button {
  margin-top: 28px;
  width: min(460px, 100%);
  padding: 18px 24px;
  border: 1px solid rgba(255, 255, 255, 0.28);
  border-radius: 8px;
  color: #041015;
  background: linear-gradient(90deg, var(--line), var(--quant) 52%, var(--sample));
  box-shadow: 0 0 24px rgba(56, 223, 240, 0.42);
  cursor: pointer;
  transition: transform 160ms ease, filter 160ms ease;
}

.start-button:hover,
.start-button:focus-visible {
  transform: translateY(-2px);
  filter: brightness(1.08);
  outline: none;
}

.start-button span,
.start-button strong {
  display: block;
}

.start-button span {
  font-size: clamp(20px, 2.8vw, 28px);
  font-weight: 1000;
}

.start-button strong {
  margin-top: 4px;
  font-size: clamp(13px, 1.7vw, 16px);
  font-weight: 900;
}

.hud {
  position: fixed;
  z-index: 7;
  top: 18px;
  left: 24px;
  right: 24px;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 20px;
  pointer-events: none;
}

.hud-main {
  min-width: 0;
}

.hud-label {
  color: var(--muted);
  font-size: 15px;
  font-weight: 800;
}

.hud-title {
  margin-top: 3px;
  font-size: clamp(28px, 4.2vw, 40px);
  line-height: 1.15;
  font-weight: 1000;
  text-shadow: 0 0 18px rgba(56, 223, 240, 0.36);
}

.hud-badges {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px;
}

.badge {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 6px 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  background: var(--panel);
  font-size: 14px;
  font-weight: 900;
  backdrop-filter: blur(12px);
}

.badge-source {
  color: var(--sample);
}

.badge.is-bumped {
  animation: badge-bump 420ms ease-out;
}

.division-controls {
  position: fixed;
  z-index: 12;
  left: 24px;
  right: auto;
  bottom: 14px;
  max-width: calc(100vw - 190px);
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 7px;
  padding: 7px;
  border: 1px solid var(--border);
  border-radius: 9px;
  background: rgba(4, 14, 19, 0.9);
  box-shadow: 0 0 22px rgba(56, 223, 240, 0.16);
  backdrop-filter: blur(14px);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 420ms ease, transform 420ms ease, visibility 420ms ease;
}

.division-mode .division-controls {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.division-value-form {
  display: flex;
  align-items: center;
  gap: 6px;
}

.division-value-input {
  width: clamp(118px, 12vw, 178px);
  min-height: 38px;
  padding: 5px 9px;
  border: 1px solid rgba(165, 238, 255, 0.28);
  border-radius: 7px;
  color: var(--sample);
  background: rgba(255, 255, 255, 0.055);
  font-family: Consolas, "Courier New", monospace;
  font-size: 18px;
  font-weight: 1000;
  outline: none;
}

.division-value-input:focus {
  border-color: var(--sample);
  box-shadow: 0 0 18px rgba(255, 209, 102, 0.22);
}

.division-value-button {
  min-width: 58px;
  min-height: 38px;
  padding: 6px 12px;
  border: 1px solid rgba(255, 209, 102, 0.4);
  border-radius: 7px;
  color: #041015;
  background: linear-gradient(90deg, var(--sample), var(--quant));
  font-size: 15px;
  font-weight: 1000;
  cursor: pointer;
  transition: transform 160ms ease, filter 160ms ease;
}

.division-value-button:hover,
.division-value-button:focus-visible {
  transform: translateY(-1px);
  filter: brightness(1.08);
  outline: none;
}

.divisor-button {
  min-width: 58px;
  min-height: 38px;
  padding: 6px 12px;
  border: 1px solid rgba(165, 238, 255, 0.24);
  border-radius: 7px;
  color: var(--text);
  background: rgba(255, 255, 255, 0.06);
  font-family: Consolas, "Courier New", monospace;
  font-size: 19px;
  font-weight: 1000;
  cursor: pointer;
  transition: transform 160ms ease, border-color 160ms ease, background 160ms ease;
}

.divisor-button:hover,
.divisor-button:focus-visible {
  transform: translateY(-1px);
  border-color: var(--line);
  outline: none;
}

.divisor-button.is-active {
  border-color: rgba(255, 255, 255, 0.78);
  color: #041015;
  background: linear-gradient(100deg, var(--line), var(--quant));
  box-shadow: 0 0 18px rgba(56, 223, 240, 0.38);
}

@keyframes badge-bump {
  0% {
    transform: scale(1);
  }
  36% {
    transform: scale(1.06);
    border-color: rgba(255, 255, 255, 0.72);
    box-shadow: 0 0 18px rgba(255, 209, 102, 0.34);
  }
  100% {
    transform: scale(1);
  }
}

.number-stage {
  position: fixed;
  z-index: 4;
  top: 112px;
  left: 24px;
  right: 24px;
  bottom: 104px;
  display: grid;
  grid-template-columns: minmax(210px, 0.96fr) minmax(310px, 1.38fr) minmax(210px, 0.96fr);
  gap: 14px;
  min-width: 0;
  transition: bottom 900ms cubic-bezier(0.22, 0.88, 0.24, 1), transform 900ms cubic-bezier(0.22, 0.88, 0.24, 1);
  touch-action: manipulation;
}

.division-mode-button {
  position: fixed;
  z-index: 12;
  top: 50%;
  right: 5px;
  width: 46px;
  height: 56px;
  display: grid;
  place-items: center;
  padding: 0;
  border: 1px solid rgba(117, 240, 154, 0.56);
  border-radius: 8px 0 0 8px;
  color: #041015;
  background: linear-gradient(135deg, var(--quant), var(--line));
  box-shadow: 0 0 18px rgba(56, 223, 240, 0.28);
  font-family: Consolas, "Courier New", monospace;
  font-size: 28px;
  font-weight: 1000;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(-50%) translateX(8px);
  transition: opacity 180ms ease, transform 180ms ease, visibility 180ms ease, filter 150ms ease;
  touch-action: manipulation;
}

.experience-started:not(.division-mode) .division-mode-button {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateY(-50%) translateX(0);
}

.division-mode-button:hover,
.division-mode-button:focus-visible {
  filter: brightness(1.1);
  outline: none;
}

.division-mode-button:active {
  transform: translateY(-50%) translateX(1px) scale(0.96);
}

.division-mode .number-stage {
  bottom: 35vh;
  transform: translateY(-18px);
}

.radix-column {
  --column-accent: var(--line);
  position: relative;
  min-width: 0;
  min-height: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr) auto;
  gap: 12px;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background:
    linear-gradient(180deg, rgba(9, 29, 36, 0.88), rgba(4, 12, 16, 0.72)),
    linear-gradient(90deg, rgba(255, 255, 255, 0.04), transparent);
  box-shadow: 0 0 24px rgba(56, 223, 240, 0.12), inset 0 0 24px rgba(255, 255, 255, 0.025);
  overflow: hidden;
}

.decimal-column {
  --column-accent: var(--sample);
}

.binary-column {
  --column-accent: var(--line);
}

.hex-column {
  --column-accent: var(--code);
}

.radix-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 10px;
  min-width: 0;
}

.radix-title {
  color: var(--text);
  font-size: clamp(24px, 3vw, 38px);
  line-height: 1.1;
  font-weight: 1000;
  text-shadow: 0 0 16px color-mix(in srgb, var(--column-accent) 62%, transparent);
}

.digit-area {
  min-width: 0;
  min-height: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.division-mode .digit-area {
  padding-right: clamp(52px, 6vw, 94px);
}

.digit-row {
  --digit-size: 48px;
  --cell-width: 42px;
  --digit-gap: 4px;
  --group-gap: 7px;
  width: 100%;
  min-width: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--digit-gap);
  font-family: Consolas, "Courier New", monospace;
}

.binary-row {
  gap: var(--group-gap);
}

.nibble-group {
  --accent: var(--line);
  min-width: 0;
  display: flex;
  align-items: stretch;
  justify-content: center;
  gap: var(--digit-gap);
  padding: clamp(2px, calc(var(--digit-size) * 0.11), 8px) clamp(2px, calc(var(--digit-size) * 0.08), 5px);
  border: 1px solid color-mix(in srgb, var(--accent) 54%, transparent);
  border-radius: 8px;
  background:
    linear-gradient(180deg, color-mix(in srgb, var(--accent) 13%, transparent), rgba(255, 255, 255, 0.018));
  box-shadow: inset 0 0 12px color-mix(in srgb, var(--accent) 14%, transparent);
}

.digit-cell {
  --accent: var(--column-accent);
  position: relative;
  width: var(--cell-width);
  min-width: var(--cell-width);
  max-width: var(--cell-width);
  padding: clamp(4px, calc(var(--digit-size) * 0.1), 8px) clamp(2px, calc(var(--digit-size) * 0.07), 6px);
  border: 1px solid color-mix(in srgb, var(--accent) 58%, transparent);
  border-radius: 7px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.07), rgba(0, 0, 0, 0.18)),
    rgba(4, 13, 18, 0.78);
  box-shadow: inset 0 0 14px rgba(255, 255, 255, 0.035), 0 0 12px color-mix(in srgb, var(--accent) 22%, transparent);
  text-align: center;
  overflow: hidden;
}

.digit-cell.is-padding {
  border-color: rgba(165, 238, 255, 0.12);
  background: rgba(4, 13, 18, 0.38);
  box-shadow: none;
}

.digit-window {
  position: relative;
  display: grid;
  grid-template-rows: calc(var(--digit-size) * 0.34) var(--digit-size) calc(var(--digit-size) * 0.34);
  align-items: center;
  justify-items: center;
  min-width: 0;
}

.hex-row .digit-window {
  grid-template-rows: calc(var(--digit-size) * 0.46) var(--digit-size) calc(var(--digit-size) * 0.38);
}

.hex-row {
  transform: translateX(3px);
}

.digit-neighbor {
  width: 100%;
  min-width: 0;
  color: var(--accent);
  font-size: clamp(8px, calc(var(--digit-size) * 0.34), 28px);
  line-height: 1;
  font-weight: 900;
  opacity: 0.34;
  text-shadow: 0 0 8px color-mix(in srgb, var(--accent) 60%, transparent);
}

.current-slot {
  width: 100%;
  height: var(--digit-size);
  overflow: hidden;
}

.roll-track {
  display: flex;
  flex-direction: column;
  transform: translateY(calc(-1 * var(--digit-size)));
}

.digit-cell.is-rolling .roll-track {
  animation: roll-up var(--roll-duration) cubic-bezier(0.22, 0.88, 0.24, 1) forwards;
}

.digit-cell.is-fast-rolling .roll-track {
  animation: fast-reel var(--fast-roll-duration) cubic-bezier(0.16, 0.72, 0.22, 1) forwards;
  will-change: transform, filter;
}

.roll-symbol {
  display: block;
  height: var(--digit-size);
  color: var(--text);
  font-size: var(--digit-size);
  line-height: var(--digit-size);
  font-weight: 1000;
  text-shadow: 0 0 18px color-mix(in srgb, var(--accent) 68%, transparent);
}

.digit-cell.is-padding .digit-neighbor,
.digit-cell.is-padding .roll-symbol {
  color: rgba(168, 192, 199, 0.42);
  text-shadow: none;
}

.division-reel-window {
  display: none;
}

.division-mode .digit-cell.is-division-reel .digit-neighbor,
.division-mode .digit-cell.is-division-reel .current-slot {
  opacity: 0;
}

.division-mode .digit-cell.is-division-reel .division-reel-window {
  position: absolute;
  inset: 0;
  display: block;
  overflow: hidden;
  pointer-events: none;
}

.division-reel-track {
  transform: translateY(var(--division-reel-start, calc(-0.66 * var(--digit-size))));
}

.division-mode .digit-cell.is-division-reel .division-reel-track {
  animation: division-reel var(--fast-roll-duration) cubic-bezier(0.16, 0.72, 0.22, 1) forwards;
  will-change: transform, filter;
}

.division-reel-symbol {
  display: block;
  height: var(--digit-size);
  color: var(--text);
  font-size: var(--digit-size);
  line-height: var(--digit-size);
  font-weight: 1000;
  text-shadow: 0 0 18px color-mix(in srgb, var(--accent) 68%, transparent);
}

.usage-grid {
  --usage-cols: 2;
  display: grid;
  grid-template-columns: repeat(var(--usage-cols), minmax(0, 1fr));
  gap: clamp(2px, calc(var(--digit-size) * 0.045), 4px);
  margin-top: clamp(4px, calc(var(--digit-size) * 0.08), 8px);
}

.usage-symbol {
  min-width: 0;
  height: clamp(9px, calc(var(--digit-size) * 0.2), 17px);
  display: grid;
  place-items: center;
  border-radius: 4px;
  color: rgba(241, 251, 255, 0.45);
  background: rgba(255, 255, 255, 0.055);
  font-size: clamp(7px, calc(var(--digit-size) * 0.16), 12px);
  line-height: 1;
  font-weight: 900;
}

.usage-symbol.is-used {
  color: #041015;
  background: color-mix(in srgb, var(--accent) 82%, #ffffff 18%);
  box-shadow: 0 0 7px color-mix(in srgb, var(--accent) 54%, transparent);
}

.usage-symbol.is-current {
  outline: 1px solid rgba(255, 255, 255, 0.9);
}

.digit-cell.is-padding .usage-grid {
  opacity: 0.32;
}

.digit-cell.is-carry-out {
  animation: carry-out 620ms ease-out;
}

.digit-cell.is-carry-in {
  animation: carry-in 700ms ease-out;
}

.digit-cell.is-used-up {
  animation: used-up-cell 420ms ease-out;
}

.digit-cell.is-used-up .usage-symbol.is-used {
  animation: used-up-symbol 420ms ease-out;
}

@keyframes roll-up {
  0% {
    transform: translateY(0);
    filter: brightness(1.4);
  }
  68% {
    filter: brightness(1.28);
  }
  100% {
    transform: translateY(calc(-1 * var(--digit-size)));
    filter: brightness(1);
  }
}

@keyframes fast-reel {
  0% {
    transform: translateY(0);
    filter: blur(0) brightness(1.5);
  }
  18% {
    filter: blur(2px) brightness(1.75);
  }
  74% {
    filter: blur(1px) brightness(1.35);
  }
  100% {
    transform: translateY(var(--roll-distance));
    filter: blur(0) brightness(1);
  }
}

@keyframes division-reel {
  0% {
    transform: translateY(var(--division-reel-start, calc(-0.66 * var(--digit-size))));
    filter: brightness(1.35);
  }
  52% {
    filter: brightness(1.55);
  }
  100% {
    transform: translateY(var(--division-reel-end));
    filter: brightness(1);
  }
}

.is-dividing .radix-column,
.division-transition .radix-column {
  border-color: color-mix(in srgb, var(--column-accent) 72%, white 28%);
  box-shadow: 0 0 34px color-mix(in srgb, var(--column-accent) 24%, transparent), inset 0 0 28px rgba(255, 255, 255, 0.05);
}

.is-dividing .digit-cell.is-carry-out,
.is-dividing .digit-cell.is-carry-in {
  animation-name: none;
}

.radix-column.is-shift-source .digit-window {
  opacity: 0;
}

.shift-digit {
  --accent: var(--line);
  --shift-x: 0px;
  position: absolute;
  z-index: 2;
  display: grid;
  place-items: center;
  pointer-events: none;
  opacity: 1;
  transform: translateX(0);
  filter: brightness(1.18);
  transition:
    transform var(--division-shift-duration) cubic-bezier(0.16, 0.78, 0.18, 1),
    filter var(--division-shift-duration) ease;
  will-change: transform, filter;
}

.shift-digit.is-shifting {
  transform: translateX(var(--shift-x));
  filter: brightness(1.45);
}

.shift-digit-decimal {
  --accent: var(--sample);
}

.shift-digit-binary {
  --accent: var(--line);
}

.shift-digit-hex {
  --accent: var(--code);
}

@keyframes used-up-cell {
  0% {
    transform: scale(1);
    border-color: color-mix(in srgb, var(--accent) 58%, transparent);
  }
  36% {
    transform: scale(1.1);
    border-color: #ffffff;
    box-shadow: 0 0 32px var(--sample), inset 0 0 24px color-mix(in srgb, var(--accent) 26%, transparent);
  }
  100% {
    transform: scale(1);
  }
}

@keyframes used-up-symbol {
  0% {
    transform: scale(1);
  }
  34% {
    transform: scale(1.22);
    filter: brightness(1.35);
  }
  100% {
    transform: scale(1);
  }
}

@keyframes carry-out {
  0% {
    transform: translateY(0) scale(1);
    border-color: var(--alert);
    box-shadow: 0 0 0 rgba(255, 92, 120, 0), inset 0 0 14px rgba(255, 255, 255, 0.035);
  }
  28% {
    transform: translateY(-3px) scale(1.08);
    border-color: #ffffff;
    box-shadow: 0 0 30px var(--alert), inset 0 0 24px rgba(255, 255, 255, 0.12);
  }
  100% {
    transform: translateY(0) scale(1);
  }
}

@keyframes carry-in {
  0% {
    transform: scale(1);
  }
  26% {
    transform: scale(1.14);
    border-color: #ffffff;
    box-shadow: 0 0 30px var(--sample), inset 0 0 24px rgba(255, 209, 102, 0.12);
  }
  100% {
    transform: scale(1);
  }
}

.metric-row {
  display: flex;
  flex-wrap: wrap;
  align-items: stretch;
  justify-content: center;
  gap: 8px;
  min-height: 50px;
}

.metric-pill {
  min-width: min(150px, 100%);
  display: inline-grid;
  grid-template-columns: auto auto;
  align-items: baseline;
  justify-content: center;
  gap: 6px;
  padding: 9px 12px;
  border: 1px solid color-mix(in srgb, var(--column-accent) 42%, transparent);
  border-radius: 8px;
  background: rgba(4, 13, 18, 0.78);
  box-shadow: 0 0 14px color-mix(in srgb, var(--column-accent) 16%, transparent);
}

.metric-pill strong {
  color: var(--column-accent);
  font-size: clamp(24px, 3vw, 36px);
  line-height: 1;
  font-weight: 1000;
  font-family: Consolas, "Courier New", monospace;
  text-shadow: 0 0 12px color-mix(in srgb, var(--column-accent) 54%, transparent);
}

.metric-pill span {
  color: var(--text);
  font-size: clamp(13px, 1.45vw, 16px);
  font-weight: 900;
}

.metric-pill.is-bumped {
  animation: metric-bump 560ms ease-out;
}

@keyframes metric-bump {
  0% {
    transform: scale(1);
  }
  32% {
    transform: scale(1.08);
    border-color: #ffffff;
    box-shadow: 0 0 28px var(--sample);
  }
  100% {
    transform: scale(1);
  }
}

.remainder-stage {
  position: fixed;
  z-index: 6;
  left: 24px;
  right: 24px;
  bottom: 94px;
  height: calc(27vh - 16px);
  min-height: 145px;
  display: grid;
  grid-template-rows: minmax(0, 1fr);
  gap: 0;
  padding: 0;
  opacity: 0;
  visibility: hidden;
  transform: translateY(34px);
  transition: opacity 720ms ease 180ms, transform 820ms cubic-bezier(0.22, 0.88, 0.24, 1) 120ms, visibility 720ms ease;
  overflow: hidden;
}

.division-mode .remainder-stage {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.remainder-track {
  min-width: 0;
  min-height: 0;
  display: grid;
  grid-template-columns: minmax(210px, 0.96fr) minmax(310px, 1.38fr) minmax(210px, 0.96fr);
  gap: 14px;
  overflow: hidden;
}

.remainder-empty {
  align-self: center;
  justify-self: center;
  color: rgba(168, 192, 199, 0.7);
  font-size: clamp(12px, 1.3vw, 16px);
  font-weight: 900;
  white-space: nowrap;
}

.remainder-radix-panel {
  --remainder-accent: var(--quant);
  min-width: 0;
  min-height: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr) auto;
  gap: 4px;
  padding: 8px 10px 8px;
  border: 1px solid color-mix(in srgb, var(--remainder-accent) 36%, transparent);
  border-radius: 9px;
  background: linear-gradient(180deg, color-mix(in srgb, var(--remainder-accent) 8%, rgba(7, 27, 29, 0.9)), rgba(4, 12, 16, 0.84));
  box-shadow: 0 0 24px color-mix(in srgb, var(--remainder-accent) 12%, transparent), inset 0 0 20px rgba(255, 255, 255, 0.02);
  overflow: hidden;
}

.remainder-radix-panel.has-nibble-summary {
  grid-template-rows: auto auto auto;
  align-content: center;
}

.remainder-decimal {
  --remainder-accent: var(--sample);
}

.remainder-binary {
  --remainder-accent: var(--line);
}

.remainder-hex {
  --remainder-accent: var(--code);
}

.remainder-radix-label {
  min-height: 22px;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  border-bottom: 1px solid color-mix(in srgb, var(--remainder-accent) 28%, transparent);
  color: var(--remainder-accent);
  font-size: clamp(14px, 1.45vw, 18px);
  font-weight: 1000;
  white-space: nowrap;
}

.remainder-values {
  min-width: 0;
  display: flex;
  gap: var(--remainder-chip-gap, 6px);
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.remainder-values.has-bit-groups {
  gap: var(--remainder-group-gap, 10px);
}

.remainder-bit-group {
  flex: 0 0 auto;
  display: flex;
  gap: var(--remainder-chip-gap, 2px);
  align-items: center;
}

.remainder-chip {
  flex: 0 0 var(--remainder-chip-width, clamp(58px, 5.4vw, 82px));
  width: var(--remainder-chip-width, clamp(58px, 5.4vw, 82px));
  min-width: 0;
  display: grid;
  grid-template-rows: auto auto;
  place-items: center;
  gap: 2px;
  padding: 4px 5px 6px;
  border: 1px solid color-mix(in srgb, var(--remainder-accent) 54%, transparent);
  border-radius: 7px;
  background: linear-gradient(180deg, color-mix(in srgb, var(--remainder-accent) 15%, transparent), rgba(4, 13, 18, 0.88));
  box-shadow: 0 0 12px color-mix(in srgb, var(--remainder-accent) 14%, transparent);
}

.remainder-chip.is-awaiting {
  opacity: 0;
}

.remainder-chip.is-landed {
  animation: remainder-land 420ms cubic-bezier(0.18, 0.9, 0.22, 1) both;
}

.remainder-place {
  color: var(--muted);
  font-family: Consolas, "Courier New", monospace;
  font-size: var(--remainder-place-size, clamp(8px, 0.9vw, 11px));
  font-weight: 900;
}

.remainder-place sup {
  font-size: 0.72em;
  line-height: 0;
}

.remainder-chip strong {
  color: var(--remainder-accent);
  font-family: Consolas, "Courier New", monospace;
  font-size: var(--remainder-font-size, clamp(21px, 2.7vw, 34px));
  line-height: 1;
  text-shadow: 0 0 14px color-mix(in srgb, var(--remainder-accent) 55%, transparent);
}

.remainder-radix-panel.is-compact .remainder-chip {
  gap: 0;
  padding: 3px 1px;
}

.remainder-radix-panel.is-compact .remainder-place {
  display: none;
}

.remainder-nibble-row {
  min-width: 0;
  min-height: 24px;
  display: flex;
  gap: var(--remainder-group-gap, 10px);
  align-items: center;
  justify-content: center;
  margin-top: -2px;
  padding-top: 0;
  border-top: 0;
  overflow: hidden;
}

.nibble-character-group {
  flex: 0 0 auto;
  min-height: 22px;
  display: grid;
  column-gap: var(--remainder-chip-gap, 2px);
  align-items: center;
}

.nibble-character-group.is-placeholder {
  visibility: hidden;
}

.nibble-character {
  min-width: 0;
  grid-column: 1 / -1;
  color: var(--code);
  text-align: center;
  font-family: Consolas, "Courier New", monospace;
  font-size: clamp(17px, 2vw, 25px);
  line-height: 1;
  text-shadow: 0 0 15px rgba(199, 161, 255, 0.58);
  animation: hex-arrive 520ms ease-out both;
}

.nibble-character.is-awaiting {
  opacity: 0;
}

.nibble-character.is-landed {
  animation: hex-arrive 520ms ease-out both, nibble-glow 720ms ease-out both;
}

@keyframes remainder-land {
  0% {
    opacity: 0.25;
    transform: scale(0.72);
    filter: brightness(1.8);
  }
  58% {
    opacity: 1;
    transform: scale(1.12);
  }
  100% {
    opacity: 1;
    transform: translate(0, 0) scale(1);
    filter: brightness(1);
  }
}

@keyframes nibble-glow {
  0%,
  100% {
    filter: brightness(1);
  }
  45% {
    filter: brightness(1.65);
  }
}

@keyframes hex-arrive {
  0% {
    opacity: 0;
    transform: translateY(-12px) scale(0.86);
  }
  100% {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

.control-bar {
  position: fixed;
  z-index: 8;
  left: 0;
  right: 0;
  bottom: 0;
  min-height: 78px;
  display: grid;
  grid-template-columns: minmax(260px, 0.8fr) minmax(150px, 0.55fr);
  align-items: center;
  gap: 12px;
  padding: 10px 24px 14px;
  background: linear-gradient(180deg, rgba(3, 9, 12, 0.68), rgba(3, 9, 12, 0.96));
  border-top: 1px solid var(--border);
  backdrop-filter: blur(14px);
}

.speed-control {
  display: grid;
  grid-template-columns: 5.2em minmax(120px, 1fr) 7.2em;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-size: 15px;
  font-weight: 900;
}

.speed-control input[type="range"] {
  min-width: 0;
  accent-color: var(--quant);
}

.speed-control output {
  color: var(--sample);
  text-align: right;
  font-weight: 1000;
  font-family: Consolas, "Courier New", monospace;
}

.division-mode .speed-control {
  opacity: 0;
  visibility: hidden;
}

.reset-button {
  justify-self: end;
  min-width: 132px;
  min-height: 46px;
  padding: 10px 18px;
  border: 1px solid rgba(255, 255, 255, 0.28);
  border-radius: 8px;
  color: #041015;
  background: linear-gradient(90deg, var(--sample), var(--alert));
  box-shadow: 0 0 22px rgba(255, 92, 120, 0.28);
  font-weight: 1000;
  cursor: pointer;
  transition: transform 150ms ease, filter 150ms ease;
}

.reset-button:hover,
.reset-button:focus-visible {
  transform: translateY(-1px);
  filter: brightness(1.08);
  outline: none;
}

.notice {
  position: fixed;
  z-index: 16;
  left: 24px;
  bottom: 100px;
  max-width: min(650px, calc(100vw - 48px));
  padding: 12px 14px;
  border: 1px solid rgba(255, 209, 102, 0.44);
  border-radius: 8px;
  color: #fff3c0;
  background: rgba(40, 29, 8, 0.92);
  box-shadow: 0 0 18px rgba(255, 209, 102, 0.18);
  font-weight: 900;
}

.step-splash {
  position: fixed;
  z-index: 15;
  inset: 0;
  display: grid;
  place-items: center;
  color: var(--text);
  font-size: clamp(48px, 9vw, 96px);
  font-weight: 1000;
  text-align: center;
  text-shadow: 0 0 26px rgba(56, 223, 240, 0.68), 0 0 54px rgba(199, 161, 255, 0.34);
  pointer-events: none;
}

.step-splash.is-visible {
  animation: splash-pop 860ms ease forwards;
}

@keyframes splash-pop {
  0% {
    opacity: 0;
    transform: scale(0.72);
  }
  18% {
    opacity: 1;
    transform: scale(1.05);
  }
  74% {
    opacity: 0.92;
    transform: scale(1);
  }
  100% {
    opacity: 0;
    transform: scale(0.96);
  }
}

.frame-flash {
  position: fixed;
  z-index: 13;
  inset: 8px;
  border: 2px solid rgba(56, 223, 240, 0);
  border-radius: 8px;
  pointer-events: none;
}

.frame-flash.is-active {
  animation: frame-flash 430ms ease-out;
}

@keyframes frame-flash {
  0% {
    border-color: rgba(56, 223, 240, 0.95);
    box-shadow: inset 0 0 20px rgba(56, 223, 240, 0.55), 0 0 24px rgba(56, 223, 240, 0.4);
  }
  100% {
    border-color: rgba(56, 223, 240, 0);
    box-shadow: none;
  }
}

.carry-layer {
  position: fixed;
  z-index: 14;
  inset: 0;
  pointer-events: none;
  overflow: hidden;
}

.remainder-flight {
  --accent: var(--quant);
  --flight-x: 0px;
  --flight-y: 0px;
  position: absolute;
  width: 70px;
  min-height: 62px;
  display: grid;
  place-items: center;
  padding: 6px 7px 8px;
  border: 1px solid color-mix(in srgb, var(--accent) 72%, white 28%);
  border-radius: 9px;
  color: var(--accent);
  background: rgba(4, 13, 18, 0.96);
  box-shadow: 0 0 24px color-mix(in srgb, var(--accent) 45%, transparent);
  opacity: 0;
  transform: scale(0.58);
  transition: opacity 180ms ease, transform 220ms cubic-bezier(0.18, 0.9, 0.22, 1);
}

.remainder-flight-decimal {
  --accent: var(--sample);
}

.remainder-flight-binary {
  --accent: var(--line);
}

.remainder-flight-hex {
  --accent: var(--code);
}

.remainder-flight.is-visible {
  opacity: 1;
  transform: scale(1);
}

.remainder-flight.is-overflow-remainder {
  --eject-distance: 64px;
  width: 58px;
  min-height: 58px;
  padding-left: 4px;
  padding-right: 4px;
  border-color: rgba(255, 255, 255, 0.9);
}

.remainder-flight.is-visible.is-ejected {
  transform: translateX(var(--eject-distance)) scale(1);
  box-shadow: 0 0 32px color-mix(in srgb, var(--accent) 68%, transparent);
  transition-duration: 180ms, var(--eject-duration, var(--division-shift-duration));
  transition-timing-function: ease, cubic-bezier(0.18, 0.82, 0.22, 1);
}

.remainder-flight.is-generated-remainder {
  filter: brightness(1.12);
}

.remainder-flight.is-stabilized {
  transition: none;
}

.remainder-flight.is-flying {
  opacity: 0.82;
  transform: translate(var(--flight-x), var(--flight-y)) scale(0.72);
  transition-duration: 420ms, 480ms;
  transition-timing-function: ease-in, cubic-bezier(0.3, 0.04, 0.5, 1);
}

.remainder-flight strong {
  max-width: 100%;
  overflow: hidden;
  font-family: Consolas, "Courier New", monospace;
  font-size: var(--remainder-font-size, 31px);
  line-height: 1;
  text-overflow: clip;
  text-shadow: 0 0 14px color-mix(in srgb, var(--accent) 58%, transparent);
}

.carry-pop,
.used-up-pop {
  --accent: var(--sample);
  position: absolute;
  left: 0;
  top: 0;
  width: 1px;
  height: 1px;
  color: var(--accent);
  font-family: "Yu Gothic", "Hiragino Kaku Gothic ProN", Meiryo, system-ui, sans-serif;
}

.carry-pop::before,
.used-up-pop::before {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -145%);
  padding: 5px 8px;
  border: 1px solid rgba(255, 255, 255, 0.72);
  border-radius: 8px;
  color: #041015;
  background: linear-gradient(90deg, var(--sample), var(--accent));
  box-shadow: 0 0 22px var(--accent);
  font-size: 13px;
  font-weight: 1000;
  white-space: nowrap;
  animation: carry-label 820ms ease-out forwards;
}

.carry-pop::before {
  content: "繰り上がり";
}

.used-up-pop::before {
  content: "使い切った";
  background: linear-gradient(90deg, var(--accent), var(--sample));
  animation: used-up-label 700ms ease-out forwards;
}

.carry-pop span,
.used-up-pop span {
  --dx: 0px;
  --dy: 0px;
  position: absolute;
  left: -3px;
  top: -3px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 12px var(--accent);
  animation: carry-spark 820ms ease-out forwards;
}

.used-up-pop span {
  border-radius: 2px;
  animation: used-up-spark 700ms ease-out forwards;
}

@keyframes carry-label {
  0% {
    opacity: 0;
    transform: translate(-50%, -80%) scale(0.8);
  }
  22% {
    opacity: 1;
    transform: translate(-50%, -145%) scale(1.08);
  }
  100% {
    opacity: 0;
    transform: translate(-50%, -210%) scale(0.95);
  }
}

@keyframes used-up-label {
  0% {
    opacity: 0;
    transform: translate(-50%, -70%) scale(0.82);
  }
  24% {
    opacity: 1;
    transform: translate(-50%, -150%) scale(1.08);
  }
  100% {
    opacity: 0;
    transform: translate(-50%, -198%) scale(0.92);
  }
}

@keyframes carry-spark {
  0% {
    opacity: 0;
    transform: translate(0, 0) scale(0.6);
  }
  18% {
    opacity: 1;
  }
  100% {
    opacity: 0;
    transform: translate(var(--dx), var(--dy)) scale(0.2);
  }
}

@keyframes used-up-spark {
  0% {
    opacity: 0;
    transform: translate(0, 0) scale(0.7) rotate(0deg);
  }
  18% {
    opacity: 1;
  }
  100% {
    opacity: 0;
    transform: translate(var(--dx), var(--dy)) scale(0.18) rotate(80deg);
  }
}

@media (max-width: 1060px) {
  .number-stage {
    top: 124px;
    gap: 10px;
    grid-template-columns: minmax(170px, 0.9fr) minmax(260px, 1.35fr) minmax(170px, 0.9fr);
  }

  .radix-column {
    padding: 12px;
  }

  .metric-pill {
    min-width: 118px;
  }

  .division-mode .number-stage {
    bottom: 37vh;
  }

  .remainder-stage {
    height: calc(28vh - 14px);
    min-height: 135px;
  }

  .remainder-track {
    grid-template-columns: minmax(170px, 0.9fr) minmax(260px, 1.35fr) minmax(170px, 0.9fr);
    gap: 10px;
  }
}

@media (max-width: 760px) {
  .hud {
    top: 12px;
    left: 14px;
    right: 14px;
    flex-direction: column;
  }

  .hud-badges {
    justify-content: flex-start;
  }

  .division-controls {
    top: auto;
    bottom: 12px;
    left: 14px;
    right: auto;
    max-width: calc(100vw - 132px);
    flex-wrap: wrap;
    justify-content: flex-start;
  }

  .division-value-form {
    flex: 1 1 100%;
    justify-content: flex-start;
  }

  .division-value-input {
    width: min(100%, 148px);
    min-height: 34px;
    font-size: 16px;
  }

  .division-value-button {
    min-height: 34px;
    padding: 5px 10px;
    font-size: 14px;
  }

  .divisor-button {
    min-width: 48px;
    min-height: 34px;
    padding: 5px 8px;
    font-size: 16px;
  }

  .number-stage {
    left: 10px;
    right: 10px;
    top: 148px;
    bottom: 110px;
    gap: 7px;
    grid-template-columns: minmax(120px, 0.85fr) minmax(180px, 1.5fr) minmax(120px, 0.85fr);
  }

  .division-mode .number-stage {
    bottom: 39vh;
    transform: translateY(-8px);
  }

  .remainder-stage {
    left: 10px;
    right: 10px;
    bottom: 104px;
    height: calc(30vh - 12px);
    min-height: 140px;
    padding: 0;
  }

  .remainder-track {
    grid-template-columns: minmax(120px, 0.85fr) minmax(180px, 1.5fr) minmax(120px, 0.85fr);
    gap: 7px;
  }

  .remainder-radix-panel {
    padding: 8px 7px;
  }

  .remainder-radix-label {
    font-size: 12px;
  }

  .radix-column {
    padding: 9px;
    gap: 8px;
  }

  .radix-title {
    font-size: 22px;
  }

  .control-bar {
    grid-template-columns: 1fr auto;
    padding-left: 14px;
    padding-right: 14px;
  }

  .speed-control {
    grid-template-columns: 4.8em minmax(90px, 1fr) 6.4em;
    font-size: 13px;
  }

  .reset-button {
    min-width: 106px;
  }
}

/*
  授業用プレゼン教材のため、OS側の reduced motion 設定では演出を止めない。
*/