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

html, body {
  width: 100%;
  height: 100%;
  min-height: 100vh;
  background: #000000;
  color: #FFFFFF;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
  position: relative;
}

#app {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 600px;
  height: 600px;
  transform: translate(-50%, -50%) scale(var(--app-scale, 1));
  transform-origin: center center;
}

.screen {
  position: absolute;
  inset: 0;
  padding: 8px;
  display: flex;
  flex-direction: column;
}

.header {
  height: 64px;
  margin-top: 16px;
  padding: 0 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header h1 {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: 0.5px;
  color: #FFFFFF;
}

.header-meta {
  font-size: 14px;
  font-weight: 500;
  color: #B0B3B8;
  padding: 4px 10px;
  border: 1px solid #3A3B3E;
  border-radius: 999px;
}

.header-meta.live {
  color: #000000;
  background: #FFFFFF;
  border-color: #FFFFFF;
}

.content {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 24px;
  padding: 0 16px;
}

.speed-readout {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.speed-value {
  font-size: 180px;
  font-weight: 800;
  line-height: 1;
  color: #FFFFFF;
  font-variant-numeric: tabular-nums;
  letter-spacing: -4px;
}

.speed-unit {
  font-size: 24px;
  font-weight: 600;
  color: #E4E6EB;
  margin-top: 4px;
  letter-spacing: 2px;
}

.level-indicator {
  width: 280px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.level-track {
  position: relative;
  width: 280px;
  height: 3px;
  background: #3A3B3E;
  border-radius: 2px;
}

.level-center-tick {
  position: absolute;
  left: 50%;
  top: -8px;
  width: 2px;
  height: 19px;
  background: #3A3B3E;
  transform: translateX(-50%);
}

.level-bubble {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 24px;
  height: 24px;
  margin: -12px 0 0 -12px;
  border-radius: 50%;
  background: #E4E6EB;
  opacity: 0.6;
  transform: translateX(0);
  transition: transform 80ms linear, background 120ms linear, opacity 120ms linear;
  will-change: transform;
}

.level-bubble.level {
  background: #FFFFFF;
  opacity: 1;
  box-shadow: 0 0 16px rgba(255, 255, 255, 0.45);
}

.top-speed {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-variant-numeric: tabular-nums;
}

.top-speed .label {
  font-size: 14px;
  font-weight: 600;
  color: #B0B3B8;
  letter-spacing: 1px;
  text-transform: uppercase;
}

.top-speed .value {
  font-size: 32px;
  font-weight: 700;
  color: #FFFFFF;
}

.top-speed .unit {
  font-size: 14px;
  font-weight: 500;
  color: #B0B3B8;
}

.nav-bar {
  display: flex;
  gap: 12px;
  padding: 0 8px 8px;
}

.nav-item {
  flex: 1;
  height: 88px;
  background: transparent;
  color: #FFFFFF;
  border: 2px solid #3A3B3E;
  border-radius: 16px;
  font-size: 18px;
  font-weight: 600;
  cursor: pointer;
  opacity: 0.8;
  transform: scale(1);
  transition: transform 120ms ease, opacity 120ms ease, border-color 120ms ease, background 120ms ease;
}

.nav-item.primary {
  border-color: #FFFFFF;
}

.focusable:focus {
  outline: none;
  opacity: 1;
  border-color: #FFFFFF;
  background: rgba(255, 255, 255, 0.08);
  transform: scale(1.04);
}

.focusable:active {
  background: rgba(255, 255, 255, 0.16);
  transform: scale(0.98);
}