body {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
  flex-direction: column;
}

#main {
  display: flex;
  flex-direction: column;
  flex: auto;
  max-height: 100%;
  max-width: 390px;
}

#timer {
  font-size: 69px;
  text-align: center;
  font-family: var(--monospace);
}

button {
  padding: 4px;
  background-color: #efefef;
  border: 1px solid #767676;
  border-radius: 5px;
  padding: 10px;
}

button > img {
  width: 40px;
  height: 40px;
}

select {
  background: url(data:image/svg+xml;base64,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) no-repeat 95% 50%;
  -moz-appearance: none;
  -webkit-appearance: none;
  appearance: none;
  height: 30px;
  width: 100%;
  font-size: 16px;
  border: 1px solid #767676;
  border-radius: 5px;
  margin-bottom: 5px;
  padding: 5px;
}