body {
  background: lightcyan;
  font-family: monospace;
  margin: 0;
  padding: 0;
}

#timer {
  text-align: center;
  font-size: 13vh;
  font-weight: 500;
  margin-top: 15rem;
}

.button-box {
  text-align: center;
}

button {
  width: 15rem;
  height: 5rem;
  font-weight: bolder;
  border: 1px solid lightgray;
  border-radius: 13px;
}

button:hover {
  cursor: pointer;
}

.btn-toggle {
  background: lightgreen;
}

.btn-reset {
  background: lightsalmon;
}

footer {
  position: absolute;
  width: 100%;
  bottom: 0;
}

footer p {
  text-align: center;
  color: gray;
}

footer p a {
  color: gray;
  text-decoration: none;
  transition: 0.3s;
}

footer p a:hover {
  color: lightslategray;
}