body{
    font-size: 30px;
}
#one{
    background: #000;
}
span{
    margin: 10px;
}
a{
    text-decoration: none;
    margin: 5px;
    color: #FFF;
}
a:hover{
    background: #FFF;
    color: green;
    border-radius: 5px;
}
.tooltip{
    position: relative;
    text-decoration: underline;
    color: purple;
}
.tooltip .tooltiptext{
    width: 220px;
    visibility: hidden;
    position: absolute;
    left: 100%;
    top: -10px;
    z-index: 1;
    border: 1px black solid;
    color: #FFF;
    border-radius: 5px;
    background: #000;
    padding: 9px;
}
.tooltip:hover .tooltiptext{
    visibility: visible;
}
.tooltip .tooltiptext::after {
    content: " ";
    position: absolute;
    top: 50%;
    right: 100%; /* To the left of the tooltip */
    margin-top: -5px;
    border-width: 5px;
    border-style: solid;
    border-color: transparent black transparent transparent;
}

.hide{
    display: none;
}
.reveal{
    display: block;
}
.timer-button{
    margin: 20px;
    background: green;
    color: white;
    font-family: Arial;
    font-size: 20px;
}
.timer-button:hover{
    color: yellow;
    border-radius: 5px;
    box-shadow: 2px 1px black
}
#timer-heading{
    color: red;
    font-size: 50px;
}
#timer-button-div{
    text-align: center;
    margin-left: 20px;
}
#timer-timeleft{
    text-align: center;
    color: lightseagreen;
}
.timeover{
    text-align: center;
}