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

body {
  font-family: "Yrsa", serif;
  line-height: 1.6;
  font-size: 18px;
}

* {
  box-sizing: border-box;
}

body {
  background: #1e1e2e;
  color: #f8f8f2;
  font-family: "Yrsa", serif;
  height: 100dvh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.demo {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3rem;
  width: 100%;
  padding: 2rem;
}
.demo__timer {
  font-size: 5rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
  color: #f8f8f2;
  line-height: 1;
  min-width: 6ch;
  text-align: center;
}
.demo__track {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 2.5rem;
}
.demo__node {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}
.demo__circle {
  --color: #44475a;
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: #2d2f3f;
  border: 3px solid var(--color);
  transition: background 0.4s, box-shadow 0.4s;
}
.demo__node--lit .demo__circle {
  background: var(--color);
  box-shadow: 0 0 24px var(--color);
}
.demo__label {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.2rem;
  opacity: 0;
  transform: translateY(4px);
  transition: opacity 0.4s, transform 0.4s;
  text-align: center;
}
.demo__node--lit .demo__label {
  opacity: 1;
  transform: translateY(0);
}
.demo__label-range {
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  opacity: 0.5;
  white-space: nowrap;
}
.demo__label-name {
  font-size: 0.85rem;
  font-weight: 600;
  white-space: nowrap;
}
.demo__btn {
  padding: 0.9rem 2.5rem;
  font-size: 1.1rem;
  font-family: "Yrsa", serif;
  font-weight: 600;
  background: #f8f8f2;
  color: #1e1e2e;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: opacity 0.2s, transform 0.1s;
}
.demo__btn:hover:not(:disabled) {
  opacity: 0.9;
  transform: translateY(-1px);
}
.demo__btn:disabled {
  opacity: 0.25;
  cursor: default;
}