style.css

html, body {
    margin: 0;
    padding: 0;
    height: 100%;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    background: black;
}

.clock {
    color: #73b66f;
    font-size: 180px;
    font-family: Stencil;
    letter-spacing: 7px;
    cursor: pointer;
    transition: font-size 0.3s ease, letter-spacing 0.3s ease;
    white-space: nowrap;
}

.menu {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: #262626;
    color: white;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    font-family: SF;
}

.menu h3 {
    margin-bottom: 10px;
}

.settings {
    display: flex;
    flex-direction: row;
    justify-content: space-around;
    width: 80%;
}

.color-options, .font-options, .toggle-options, .spacing-options {
    margin: 0 20px;
}

.color-option, .font-option, .toggle-option {
    padding: 10px;
    cursor: pointer;
    border-radius: 10px;
}

.color-option:hover, .font-option:hover, .toggle-option:hover {
    background: #444;
}

button {
    padding: 10px 20px;
    font-size: 18px;
    cursor: pointer;
    background: #555;
    border: none;
    color: white;
    margin-top: 20px;
    border-radius: 20px;
    font-family: SF;
}

button:hover {
    background: #777;
}

input[type="checkbox"] {
    margin-right: 10px;
}

input[type="range"] {
    width: 100%;
}