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

body {
  font-family: sans-serif;
  background: #f5f5f5;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  padding: 16px;
}

.container {
  background: #fff;
  border-radius: 12px;
  padding: 32px 24px;
  width: 100%;
  max-width: 360px;
  text-align: center;
  box-shadow: 0 2px 12px rgba(0,0,0,0.1);
}

h1 {
  font-size: 1.4rem;
  margin-bottom: 24px;
  color: #333;
}

.display {
  font-size: 4rem;
  font-weight: bold;
  letter-spacing: 0.05em;
  color: #222;
  margin-bottom: 24px;
  font-variant-numeric: tabular-nums;
}

.display.running {
  color: #2a7ae2;
}

.display.finished {
  color: #e53935;
}

.input-area {
  display: flex;
  justify-content: center;
  align-items: flex-end;
  gap: 8px;
  margin-bottom: 24px;
}

.input-area label {
  display: flex;
  flex-direction: column;
  align-items: center;
  font-size: 0.8rem;
  color: #666;
  gap: 4px;
}

.input-area input {
  width: 72px;
  font-size: 1.4rem;
  text-align: center;
  padding: 6px 4px;
  border: 1px solid #ccc;
  border-radius: 6px;
}

.sep {
  font-size: 1.6rem;
  padding-bottom: 6px;
  color: #666;
}

.buttons {
  display: flex;
  gap: 8px;
  justify-content: center;
}

button {
  flex: 1;
  padding: 12px 0;
  font-size: 1rem;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  background: #e0e0e0;
  color: #333;
  transition: background 0.15s;
}

button:disabled {
  opacity: 0.4;
  cursor: default;
}

#startBtn {
  background: #2a7ae2;
  color: #fff;
}

#startBtn:hover:not(:disabled) {
  background: #1a5dbf;
}

#pauseBtn {
  background: #ff9800;
  color: #fff;
}

#pauseBtn:hover:not(:disabled) {
  background: #e65100;
}

#resetBtn:hover {
  background: #bdbdbd;
}