body {
    margin: 0px;
    padding: 0px;
    font-size: 16px;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}
.container {
    /* background-color: red; */
    text-align: center;
}
.container > h1 {
    color: aliceblue;
    font-weight: 400;
}
canvas {
    margin: 10px 20px;
}
.container > .footer {
    margin-top: 20px;
    margin-bottom: 20px;
    color: aliceblue;
    font-weight: 200;
}
.history-btn {
    padding: 10px 20px;
    font-size: 16px;
    background: #2c7be5;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
}
.history-btn:hover {
    background: #1a5dc9;
}
.clear-btn {
    background: red;
    color: white;
    border: none;
    padding: 8px 15px;
    border-radius: 5px;
    cursor: pointer;
}
.clear-btn:hover {
    background: darkred;
}