/* ============================================================
   万码归一 · 二进制极速挑战  — Cyberpunk Dark Theme v2
   ============================================================ */
:root {
  --neon-green: #00ff9d;
  --neon-cyan: #00e5ff;
  --neon-purple: #b84fff;
  --neon-pink: #ff2d78;
  --neon-yellow: #ffe600;
  --bg-dark: #050a0f;
  --text-main: #e0ffe8;
  --text-dim: rgba(200, 255, 220, 0.45);
  --border: rgba(0, 255, 157, 0.18);
  --border-hot: rgba(0, 255, 157, 0.6);
  --font-mono: 'Share Tech Mono', monospace;
  --font-display: 'Orbitron', sans-serif;
  --font-ui: 'Noto Sans SC', sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html,
body {
  height: 100%;
  background: var(--bg-dark);
  color: var(--text-main);
  font-family: var(--font-ui);
  overflow: hidden;
  user-select: none;
}

/* Matrix canvas */
#matrixCanvas {
  position: fixed;
  inset: 0;
  z-index: 0;
  opacity: 0.18;
  pointer-events: none;
}

#bgOverlay {
  position: fixed;
  inset: 0;
  z-index: 1;
  background-size: cover;
  background-position: center;
  pointer-events: none;
}

/* Scanlines */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  z-index: 2;
  background: repeating-linear-gradient(0deg, transparent, transparent 2px, rgba(0, 0, 0, .05) 2px, rgba(0, 0, 0, .05) 4px);
  pointer-events: none;
}

/* ── Header ── */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 24px;
  background: rgba(5, 10, 15, .8);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}

.header-left {
  display: flex;
  align-items: center;
  gap: 14px;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-badge {
  font-family: var(--font-display);
  font-size: 1.4rem;
  font-weight: 900;
  color: var(--bg-dark);
  background: linear-gradient(135deg, var(--neon-green), var(--neon-cyan));
  padding: 3px 10px;
  border-radius: 7px;
  box-shadow: 0 0 18px rgba(0, 255, 157, .5);
  letter-spacing: 2px;
}

.main-title {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
  background: linear-gradient(90deg, var(--neon-green), var(--neon-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: 3px;
}

.sub-title {
  font-size: .7rem;
  color: var(--text-dim);
  letter-spacing: 2px;
}

.btn-setting {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 7px;
  color: var(--neon-cyan);
  font-family: var(--font-ui);
  font-size: .8rem;
  cursor: pointer;
  transition: all .25s;
}

.btn-setting:hover {
  border-color: var(--neon-cyan);
  background: rgba(0, 229, 255, .08);
  box-shadow: 0 0 12px rgba(0, 229, 255, .25);
}

/* ── Screens ── */
.main-content {
  position: fixed;
  inset: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: center;
  padding-top: 60px;
}

.screen {
  display: none;
  width: 100%;
  height: 100%;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 18px;
  overflow-y: auto;
}

.screen.active {
  display: flex;
}

/* ── Idle ── */
.idle-content {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}

.pulse-ring {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 180px;
  height: 180px;
  border-radius: 50%;
  border: 2px solid var(--neon-green);
  transform: translate(-50%, -50%) scale(.5);
  animation: pulse-expand 2.5s ease-out infinite;
  opacity: 0;
}

.pulse-ring.delay1 {
  animation-delay: .8s;
}

.pulse-ring.delay2 {
  animation-delay: 1.6s;
}

@keyframes pulse-expand {
  0% {
    transform: translate(-50%, -50%) scale(.5);
    opacity: .8
  }

  100% {
    transform: translate(-50%, -50%) scale(2.5);
    opacity: 0
  }
}

.idle-icon {
  font-size: 4.5rem;
  filter: drop-shadow(0 0 18px var(--neon-green));
  animation: float 3s ease-in-out infinite;
}

@keyframes float {

  0%,
  100% {
    transform: translateY(0)
  }

  50% {
    transform: translateY(-10px)
  }
}

.idle-text {
  font-size: 1.5rem;
  font-family: var(--font-display);
  letter-spacing: 2px;
  text-shadow: 0 0 18px var(--neon-green);
}

.idle-sub {
  color: var(--text-dim);
  font-size: .85rem;
  letter-spacing: 1px;
}

kbd {
  display: inline-block;
  padding: 2px 8px;
  background: rgba(0, 255, 157, .1);
  border: 1px solid var(--neon-green);
  border-radius: 5px;
  color: var(--neon-green);
  font-family: var(--font-mono);
  font-size: .9em;
  box-shadow: 0 0 6px rgba(0, 255, 157, .2);
}

/* ── Challenge — Status Bar ── */
.status-bar {
  display: flex;
  gap: 40px;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
}

/* Progress */
.progress-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.progress-dots {
  display: flex;
  gap: 7px;
  flex-wrap: wrap;
  max-width: 280px;
  justify-content: center;
}

.prog-dot {
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background: rgba(255, 255, 255, .08);
  border: 2px solid rgba(255, 255, 255, .12);
  transition: all .3s;
}

.prog-dot.active {
  background: rgba(0, 229, 255, .25);
  border-color: var(--neon-cyan);
  box-shadow: 0 0 10px var(--neon-cyan);
  transform: scale(1.3);
}

.prog-dot.done-ok {
  background: var(--neon-green);
  border-color: var(--neon-green);
  box-shadow: 0 0 8px rgba(0, 255, 157, .6);
}

.prog-dot.done-wrong {
  background: var(--neon-pink);
  border-color: var(--neon-pink);
  box-shadow: 0 0 8px rgba(255, 45, 120, .5);
}

.prog-dot.done-skip {
  background: #444;
  border-color: #666;
}

.progress-label {
  font-family: var(--font-display);
  font-size: .7rem;
  color: var(--text-dim);
  letter-spacing: 3px;
}

/* Timer */
.timer-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 5px;
}

.timer-label {
  font-size: .65rem;
  letter-spacing: 3px;
  color: var(--text-dim);
  text-transform: uppercase;
}

.timer-display {
  font-family: var(--font-display);
  font-size: 2.6rem;
  font-weight: 700;
  color: var(--neon-green);
  text-shadow: 0 0 24px var(--neon-green);
  transition: color .3s;
}

.timer-display.warning {
  color: var(--neon-yellow);
  text-shadow: 0 0 24px var(--neon-yellow);
}

.timer-display.danger {
  color: var(--neon-pink);
  text-shadow: 0 0 24px var(--neon-pink);
  animation: blink .5s step-end infinite;
}

@keyframes blink {

  0%,
  100% {
    opacity: 1
  }

  50% {
    opacity: .3
  }
}

.timer-bar-bg {
  width: 140px;
  height: 3px;
  background: rgba(255, 255, 255, .08);
  border-radius: 2px;
  overflow: hidden;
}

.timer-bar {
  height: 100%;
  width: 100%;
  background: linear-gradient(90deg, var(--neon-green), var(--neon-cyan));
  border-radius: 2px;
  transition: width 1s linear, background .3s;
  box-shadow: 0 0 6px var(--neon-green);
}

/* Live Score */
.live-score-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.live-score {
  font-family: var(--font-display);
  font-size: 2.6rem;
  font-weight: 700;
  color: var(--neon-cyan);
  text-shadow: 0 0 20px var(--neon-cyan);
}

.score-badge-row {
  font-size: .8rem;
  color: var(--neon-yellow);
  letter-spacing: 2px;
  min-height: 1.2rem;
}

/* ── Question ── */
.question-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
}

.question-meta {
  display: flex;
  align-items: center;
  gap: 12px;
}

.question-label {
  font-size: .65rem;
  letter-spacing: 4px;
  color: var(--text-dim);
  text-transform: uppercase;
}

.diff-badge {
  font-size: .7rem;
  padding: 2px 10px;
  border: 1px solid;
  border-radius: 20px;
  letter-spacing: 2px;
  font-family: var(--font-display);
}

.decimal-number {
  font-family: var(--font-display);
  font-size: 6rem;
  font-weight: 900;
  line-height: 1;
  background: linear-gradient(135deg, var(--neon-cyan), var(--neon-green), var(--neon-purple));
  background-size: 200%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  animation: grad-shift 4s linear infinite;
  filter: drop-shadow(0 0 24px rgba(0, 229, 255, .45));
  transition: filter .5s, opacity .5s;
}

@keyframes grad-shift {
  0% {
    background-position: 0%
  }

  50% {
    background-position: 100%
  }

  100% {
    background-position: 0%
  }
}

.decimal-number.pop {
  animation: pop .2s ease-out, grad-shift 4s linear infinite;
}

@keyframes pop {
  0% {
    transform: scale(1.18)
  }

  100% {
    transform: scale(1)
  }
}

.question-hint {
  font-family: var(--font-mono);
  font-size: 1.1rem;
  color: var(--neon-purple);
  letter-spacing: 2px;
  min-height: 1.4rem;
}

.decimal-number.char-mode {
  background: linear-gradient(135deg, var(--neon-purple), var(--neon-pink), var(--neon-yellow));
  background-size: 200%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  filter: drop-shadow(0 0 26px rgba(184, 79, 255, .6));
}

.hint-tip {
  color: var(--text-dim);
  font-size: 0.85rem;
  letter-spacing: 1px;
}

.answer-num-tip {
  margin-left: 12px;
  font-size: 0.85rem;
  color: var(--neon-purple);
  font-family: var(--font-mono);
  background: rgba(184, 79, 255, 0.12);
  border: 1px solid rgba(184, 79, 255, 0.35);
  border-radius: 6px;
  padding: 2px 8px;
  display: inline-block;
  vertical-align: middle;
}

/* 平板/触屏设备点击无延迟及去除高亮框 */
.bit-card, .btn-clear, .btn-reveal, .btn-restart, .fab-btn, .idle-screen {
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}

/* ── Binary Cards ── */
.binary-section {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.binary-label-row {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: .7rem;
  letter-spacing: 2px;
  color: var(--text-dim);
}

.binary-label-text {
  text-transform: uppercase;
}

.btn-clear,
.btn-reveal {
  padding: 4px 12px;
  border-radius: 20px;
  font-family: var(--font-ui);
  font-size: .78rem;
  cursor: pointer;
  transition: all .25s;
  border: 1px solid;
}

.btn-clear {
  background: rgba(0, 229, 255, .08);
  border-color: rgba(0, 229, 255, .35);
  color: var(--neon-cyan);
}

.btn-clear:hover {
  background: rgba(0, 229, 255, .18);
  box-shadow: 0 0 10px rgba(0, 229, 255, .3);
}

.btn-reveal {
  background: rgba(184, 79, 255, .1);
  border-color: rgba(184, 79, 255, .4);
  color: var(--neon-purple);
}

.btn-reveal:hover {
  background: rgba(184, 79, 255, .22);
  box-shadow: 0 0 12px rgba(184, 79, 255, .35);
}

.binary-cards {
  display: flex;
  gap: 7px;
}

.bit-card {
  width: 62px;
  height: 76px;
  border-radius: 11px;
  border: 2px solid var(--border);
  background: rgba(0, 255, 157, .03);
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  color: rgba(0, 255, 157, .2);
  cursor: pointer;
  transition: all .2s cubic-bezier(.34, 1.56, .64, 1);
  display: flex;
  align-items: center;
  justify-content: center;
}

.bit-card:hover {
  border-color: rgba(0, 229, 255, .5);
  transform: scale(1.06);
  background: rgba(0, 229, 255, .07);
}

.bit-card.bit-on {
  color: var(--neon-green);
  border-color: var(--neon-green);
  background: rgba(0, 255, 157, .1);
  box-shadow: 0 0 16px rgba(0, 255, 157, .3), inset 0 0 10px rgba(0, 255, 157, .07);
  transform: translateY(-3px) scale(1.04);
}

/* 揭示后 */
.bit-card.bit-reveal {
  cursor: default;
  transition-delay: 0ms;
}

.bit-card.bit-zero-ok {
  color: rgba(0, 229, 255, .4);
  border-color: rgba(0, 229, 255, .2);
}

.bit-card.bit-wrong {
  color: var(--neon-pink);
  border-color: var(--neon-pink);
  background: rgba(255, 45, 120, .08);
  box-shadow: 0 0 12px rgba(255, 45, 120, .25);
}

.bit-labels,
.bit-values {
  display: flex;
  gap: 7px;
}

.bit-labels span,
.bit-values span {
  width: 62px;
  text-align: center;
  font-family: var(--font-mono);
}

.bit-labels span {
  font-size: 1.2rem;
  color: var(--text-dim);
}

.bit-values span {
  font-size: 1.2em;
  color: rgba(184, 79, 255, .5);
}

/* ── Answer Reveal ── */
.answer-reveal {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 12px 28px;
  background: rgba(0, 255, 157, .04);
  border: 1px solid var(--border-hot);
  border-radius: 14px;
  animation: fadeIn .3s ease-out;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(6px)
  }

  to {
    opacity: 1;
    transform: translateY(0)
  }
}

.answer-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.answer-label {
  font-size: .75rem;
  color: var(--text-dim);
  letter-spacing: 2px;
}

.answer-binary {
  font-family: var(--font-display);
  font-size: 1.8rem;
  font-weight: 700;
  letter-spacing: 6px;
}

.bit-ok {
  color: var(--neon-green);
}

.bit-err {
  color: var(--neon-pink);
  text-decoration: underline;
}

.answer-judge {
  font-size: .9rem;
  letter-spacing: 2px;
}

.judge-correct {
  color: var(--neon-green);
  text-shadow: 0 0 12px var(--neon-green);
}

.judge-wrong {
  color: var(--neon-pink);
  text-shadow: 0 0 12px var(--neon-pink);
}

/* ── Action Tips ── */
.action-tips {
  display: flex;
  gap: 20px;
  font-size: .72rem;
  color: var(--text-dim);
  letter-spacing: 1px;
  flex-wrap: wrap;
  justify-content: center;
}

/* ── Settings ── */
.settings-backdrop {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 200;
  background: rgba(5, 10, 15, .7);
  backdrop-filter: blur(4px);
}

.settings-backdrop.open {
  display: block;
}

.settings-panel {
  position: fixed;
  top: 50%;
  left: 50%;
  z-index: 201;
  transform: translate(-50%, -50%) scale(.9);
  width: 380px;
  max-width: 90vw;
  background: rgba(5, 10, 15, .96);
  border: 1px solid var(--border-hot);
  border-radius: 18px;
  padding: 28px;
  box-shadow: 0 0 50px rgba(0, 255, 157, .12), 0 20px 60px rgba(0, 0, 0, .8);
  opacity: 0;
  pointer-events: none;
  transition: all .3s cubic-bezier(.34, 1.56, .64, 1);
}

.settings-panel.open {
  opacity: 1;
  pointer-events: auto;
  transform: translate(-50%, -50%) scale(1);
}

.settings-content h3 {
  font-family: var(--font-display);
  font-size: 1rem;
  color: var(--neon-green);
  letter-spacing: 3px;
  margin-bottom: 22px;
}

.settings-content label {
  display: flex;
  flex-direction: column;
  gap: 7px;
  margin-bottom: 18px;
}

.settings-content label>span {
  font-size: .78rem;
  color: var(--text-dim);
  letter-spacing: 2px;
}

.settings-content input[type="number"],
.settings-content select {
  background: rgba(0, 255, 157, .04);
  border: 1px solid var(--border);
  border-radius: 7px;
  color: var(--text-main);
  font-family: var(--font-mono);
  font-size: .95rem;
  padding: 9px 12px;
  outline: none;
  width: 100%;
  transition: border-color .25s;
}

.settings-content input:focus,
.settings-content select:focus {
  border-color: var(--neon-green);
}

.toggle-label {
  flex-direction: row !important;
  align-items: center;
  gap: 12px !important;
}

.toggle-label>span:first-child {
  flex: 1;
}

.toggle-label input[type="checkbox"] {
  display: none;
}

.toggle-slider {
  width: 42px;
  height: 22px;
  border-radius: 11px;
  background: rgba(255, 255, 255, .1);
  border: 1px solid var(--border);
  position: relative;
  cursor: pointer;
  transition: background .3s;
  flex-shrink: 0;
}

.toggle-slider::after {
  content: '';
  position: absolute;
  top: 3px;
  left: 3px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--text-dim);
  transition: all .3s;
}

.toggle-label input:checked+.toggle-slider {
  background: rgba(0, 255, 157, .2);
  border-color: var(--neon-green);
}

.toggle-label input:checked+.toggle-slider::after {
  left: 23px;
  background: var(--neon-green);
  box-shadow: 0 0 7px var(--neon-green);
}

.btn-close-settings {
  width: 100%;
  padding: 11px;
  background: linear-gradient(135deg, rgba(0, 255, 157, .14), rgba(0, 229, 255, .08));
  border: 1px solid var(--neon-green);
  border-radius: 9px;
  color: var(--neon-green);
  font-family: var(--font-display);
  font-size: .85rem;
  letter-spacing: 3px;
  cursor: pointer;
  transition: all .25s;
}

.btn-close-settings:hover {
  background: rgba(0, 255, 157, .18);
  box-shadow: 0 0 18px rgba(0, 255, 157, .25);
}

/* ── FABs ── */
.fab-settings {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 100;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: rgba(5, 10, 15, .85);
  border: 1px solid var(--border);
  color: var(--neon-green);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all .25s;
  backdrop-filter: blur(8px);
}

.fab-settings:hover {
  border-color: var(--neon-green);
  box-shadow: 0 0 18px rgba(0, 255, 157, .35);
  transform: rotate(30deg);
}

.fab-ascii {
  position: fixed;
  bottom: 82px;
  right: 22px;
  z-index: 100;
  padding: 7px 12px;
  border-radius: 10px;
  background: rgba(5, 10, 15, .85);
  border: 1px solid rgba(184, 79, 255, .4);
  color: var(--neon-purple);
  font-family: var(--font-mono);
  font-size: .75rem;
  cursor: pointer;
  transition: all .25s;
  backdrop-filter: blur(8px);
}

.fab-ascii:hover {
  border-color: var(--neon-purple);
  box-shadow: 0 0 14px rgba(184, 79, 255, .3);
}

/* ── ASCII Table Panel ── */
.ascii-table-panel {
  position: fixed;
  bottom: 130px;
  right: 20px;
  z-index: 150;
  width: 320px;
  max-height: 380px;
  overflow-y: auto;
  background: rgba(5, 10, 15, .96);
  border: 1px solid rgba(184, 79, 255, .5);
  border-radius: 14px;
  padding: 14px;
  box-shadow: 0 0 30px rgba(184, 79, 255, .15);
}

.ascii-panel-title {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-display);
  font-size: .8rem;
  color: var(--neon-purple);
  letter-spacing: 2px;
  margin-bottom: 10px;
}

.ascii-panel-title button {
  background: transparent;
  border: none;
  color: var(--text-dim);
  cursor: pointer;
  font-size: 1rem;
}

.ascii-table {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 4px;
}

.ascii-cell {
  background: rgba(184, 79, 255, .05);
  border: 1px solid rgba(184, 79, 255, .15);
  border-radius: 6px;
  padding: 4px;
  text-align: center;
  transition: background .2s;
  cursor: default;
}

.ascii-cell:hover {
  background: rgba(184, 79, 255, .12);
}

.ac-dec {
  display: block;
  font-family: var(--font-mono);
  font-size: .65rem;
  color: var(--text-dim);
}

.ac-char {
  display: block;
  font-family: var(--font-mono);
  font-size: .9rem;
  color: var(--neon-purple);
}

/* ── Score Overlay ── */
.score-overlay {
  position: fixed;
  inset: 0;
  z-index: 300;
  background: rgba(5, 10, 15, .92);
  backdrop-filter: blur(12px);
  display: flex;
  align-items: center;
  justify-content: center;
  animation: fadeIn .4s ease-out;
}

.score-box {
  width: min(640px, 94vw);
  padding: 36px 40px;
  background: rgba(0, 255, 157, .03);
  border: 1px solid var(--neon-green);
  border-radius: 22px;
  box-shadow: 0 0 60px rgba(0, 255, 157, .12);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
  max-height: 90vh;
  overflow-y: auto;
}

.score-title {
  font-family: var(--font-display);
  font-size: 1.4rem;
  color: var(--neon-cyan);
  letter-spacing: 4px;
}

.score-medals {
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.score-big {
  font-family: var(--font-display);
  font-size: 5rem;
  font-weight: 900;
  color: var(--neon-green);
  text-shadow: 0 0 28px var(--neon-green);
  line-height: 1;
}

.score-slash {
  font-family: var(--font-display);
  font-size: 2.5rem;
  color: var(--text-dim);
}

.score-total {
  font-family: var(--font-display);
  font-size: 2.5rem;
  color: var(--text-dim);
}

/* Chapter */
.chapter-badge {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 700;
  border: 2px solid;
  border-radius: 14px;
  padding: 8px 28px;
  letter-spacing: 4px;
}

.chapter-rule {
  font-size: .72rem;
  color: var(--text-dim);
  letter-spacing: 1px;
  text-align: center;
  line-height: 1.8;
}

/* Detail grid */
.score-detail-grid {
  width: 100%;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.sd-row {
  display: flex;
  gap: 8px;
  align-items: center;
  padding: 6px 12px;
  border-radius: 8px;
  border: 1px solid;
  font-size: .8rem;
}

.sd-ok {
  border-color: rgba(0, 255, 157, .25);
  background: rgba(0, 255, 157, .04);
}

.sd-wrong {
  border-color: rgba(255, 45, 120, .2);
  background: rgba(255, 45, 120, .04);
}

.sd-skip {
  border-color: rgba(255, 255, 255, .08);
  background: rgba(255, 255, 255, .02);
}

.sd-num {
  font-family: var(--font-display);
  font-size: .7rem;
  color: var(--text-dim);
  width: 28px;
}

.sd-diff {
  font-size: .68rem;
  width: 36px;
}

.sd-dec {
  font-family: var(--font-mono);
  width: 36px;
  color: var(--neon-cyan);
}

.sd-bin {
  font-family: var(--font-mono);
  letter-spacing: 3px;
  flex: 1;
  color: var(--text-main);
}

.sd-result {
  font-size: .9rem;
}

.btn-restart {
  padding: 12px 36px;
  background: linear-gradient(135deg, rgba(0, 255, 157, .14), rgba(0, 229, 255, .08));
  border: 1px solid var(--neon-green);
  border-radius: 11px;
  color: var(--neon-green);
  font-family: var(--font-display);
  font-size: .9rem;
  letter-spacing: 2px;
  cursor: pointer;
  transition: all .25s;
}

.btn-restart:hover {
  background: rgba(0, 255, 157, .2);
  box-shadow: 0 0 24px rgba(0, 255, 157, .35);
  transform: translateY(-2px);
}

/* Responsive */
@media (max-width:680px) {
  .decimal-number {
    font-size: 4rem;
  }

  .bit-card {
    width: 42px;
    height: 58px;
    font-size: 1.5rem;
  }

  .bit-labels span,
  .bit-values span {
    width: 42px;
    font-size: 2rem;
  }

  .binary-cards {
    gap: 4px;
  }

  .status-bar {
    gap: 20px;
  }
}