body{
  margin: 20px auto;
  max-width: 850px;
  line-height: 1.8;
  font-size: 18px;
  color: #444;
  background-color: #eee;
}

table, th, td {
  border: 1px solid black;
  border-collapse: collapse;
  padding: 10px
}

input[type="number"] {
  width: 2.5em;
  background-color: #eee;
  color: #444;
  font-size: 18px;
  font-weight: 700;
  padding-left: 6px;
}

.tooltip {
  position: relative;
  display: inline-block;
  cursor: pointer;
  padding-left: 5px;
}

.tooltiptext {
  visibility: hidden;
  width: 130px;
  font-size: 14px;
  background-color: rgb(180, 180, 180);
  color: #1a1a1a;
  text-align: center;
  padding: 2px 5px 5px;
  border-radius: 6px;
  position: absolute;
  z-index: 1;
}

.tooltip:hover .tooltiptext {
  visibility: visible;
}