#main {
  display: inline-block;
  float: center;
  max-width: 600px
}

body {
  text-align: center;
}

body, td, button, select, input {
  background: black;
  color: white;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  font-size: 16px;
}

p {
  text-align: left;
}

h1 {
  color: #00dd00;
  -webkit-text-stroke: 2px rgba(255,255,255, 0.05);
}

input, button, select {
  min-width: 72px;
  height: 56px;
  margin: 6px;
  font-size: 24px;
  border: 4px solid white;
  border-radius: 8px;
}

button {
  transition: 100ms;
}

@keyframes pulse {
    0% {
      border: 4px solid #003000;
    }

    75% {
      border: 4px solid #006000;
    }
}

#opgave {
  font-size: 24px;
  margin: 16px;
  font-weight: bold;
  padding: 6px;
  transition: 250ms;
}

#tid {
  font-size: 24px;
  margin: 16px;
  padding: 6px;
}

/*  animation: pulse 1s ease-in-out infinite; */

.smallbutton {
  height: 36px;
  font-size: 16px;
}

.symbol {
  vertical-align: 10px;
  font-size: 48px;
}

button:active {
  transform: scale(1.3);
  background-color: #808080;
}

select {
  text-align: left;
  min-width: 160px;
}

#settings td {
  text-align: left;
  font-size: 24px;
}

#settings button {
  width: 100%;
}

a {
  color: #00aa00;
}

#tabel table {
  border-spacing: 4px;
}

#tabel td {
  padding: 0;
  font-size: 15px;
  color: #00aa00;
}

.datacell {
  padding: 0;
  width: 19px;
  height: 19px;
  border-radius: 4px;
  background: #161b22;
  outline: 2px solid rgba(255,255,255, 0.1);
  outline-offset: -2px;
}

.activecell {
  outline: 2px solid rgba(255,255,255, 0.8);
}