style.css

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    background-image: linear-gradient(to right, rgb(248, 244, 244), crimson);
}

.title {
    font-size: 50px;
    text-align: center;
    margin: 10% 0 50px 0;
}

.stopwatch {
    display: grid;
    justify-content: center;
}

.display {
    grid-row: 1;
    text-align: center;
    font-size: 50px;
    background-color: white;
    border-radius: 5px;
    border: solid 2px black;
    margin-bottom: 5px;
    width: 450px;
}

.buttons {
    text-align: center;
}

button {
    grid-row: 2;
    height: 50px;
    width: 147px;
    border: solid 2px black;
    border-radius: 5px;
    background-color: white;
    cursor: pointer;
    font-size: 20px;
}

button:hover {
    background-color: crimson;
    color: white;
}