Timer

Pure HTML + React JS / TS

body,
html {
  margin: 0;
  padding: 0;
  height: 100%;
  font-family: Arial, sans-serif;
  display: flex;
  justify-content: center;
  align-items: center;
  background-color: #282c34;
  color: white;
}

#app {
  text-align: center;
}

#timer-input {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

#minutes {
  font-size: 1.5em;
  padding: 5px;
  text-align: center;
  border-radius: 5px;
  border: 1px solid #ccc;
}

button {
  font-size: 1.2em;
  padding: 10px;
  border: none;
  border-radius: 5px;
  background-color: #61dafb;
  color: black;
  cursor: pointer;
}

button:hover {
  background-color: #21a1f1;
}

#timer-display {
  display: flex;
  flex-direction: column;
  gap: 20px;
  align-items: center;
}

#time-left {
  font-size: 4em;
  font-weight: bold;
}

.hidden {
  display: none;
}

HTML TimerJS TimerTS Timer