* {
    margin: 0;
    padding: 0;
}

body {
    background-color: #000;
    color: #fff;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 16px;
}

h2 {
    font-weight: normal;
}

#stopw {
    display: flex;
    flex-wrap: wrap;
    max-width: 30rem;
    margin: 50px auto;
    text-align: center;
}

.unit {
    display: flex;
    align-items: baseline;
    width: 33.33%;
    font-size: 3rem;
}

.unit label {
    font-size: 50%;
}

.btn-wrap {
    width: 100%;
    margin-top: 3rem;
}

.btn {
    margin: 0 0.3em;
    padding: 0.5em 1em;
    border: 0;
    border-radius: 5px;
    color: #fff;
    font-size: 1.2rem;
    cursor: pointer;
    outline: none;
}

#btn-toggle {
    background-color: #20b84c;
}

#btn-reset {
    background-color: #ba4949;
}

#laps {
    width: 100%;
    margin-top: 3rem;
    list-style: none;
}

#laps li {
    padding: 0.5em 0;
    border-top: 1px solid rgba(155, 155, 155, 0.15);
}

#laps .erase {
    padding-left: 0.3em;
    color: #666;
    font-weight: bold;
    cursor: pointer;
}