html {
  box-sizing: border-box;
  font-size: 62.5%;
}
*,
*:before,
*:after {
  box-sizing: inherit;
}
body {
  font-family: --apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen,
    Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
}
.header {
  position: fixed;
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  justify-content: space-evenly;
  align-items: center;
  bottom: 0px;
  left: 0;
  width: 100vw;
  z-index: 1;
  padding: 10px 0;
  background-color: #0a1a1f;
  color: #fff;
  font-size: 1.5rem;
}
button {
  padding: 15px;
  border: none;
  background-color: #18b28e;
  color: #0b1a1f;
  font-weight: bold;
}
button:disabled,
button[disabled] {
  background-color: #c0eee3;
  color: #666666;
}