style.css

html, body {
    background: #ffffff;
    font-family:'Gill Sans', 'Gill Sans MT', Calibri, 'Trebuchet MS', sans-serif;
}

::selection {
    background: #73a4ce7c;
    color: #444444;
}

.root {
    display: flex;
    flex-direction: column;
    padding: 4em 0;
}

.logo {
    --size: 0;
    --rotate: 0;
    --r-size: calc(var(--size) * 8em + 8em);
    --r-rotate: calc(var(--rotate) * 360deg);
    width: var(--r-size);
    height: var(--r-size);
    align-self: center;
    background: linear-gradient(to bottom, #009fff, #f5445e);
    overflow: hidden;
    border-radius: 4em;
}

.logo > img {
    transition: transform 150ms ease-out;
    filter: drop-shadow(var(--r-size) 0 #ffffff);
    mix-blend-mode: screen;
    transform: translateX(-100%) rotate(var(--r-rotate));
    transform-origin: calc(var(--r-size) * 1.5) calc(var(--r-size) * 0.5);
}

.title {
    align-self: center;
    font-size: 3em;
    font-weight: bold;
    color: #888888;
    margin-top: 1.6em;
    margin-bottom: 0.2em;
}

.info {
    align-self: center;
    color: #888888;
    font-style: italic;
    margin-bottom: 2em;
}

.box {
    max-width: 32em;
    width: calc(100% - 8em);
    background: #eeeeee;
    display: flex;
    flex-direction: column;
    padding: 2em;
    border-radius: 2em;
    align-self: center;
    margin: 2em 0;
}

input {
    transition: all 150ms;
    border: none;
    padding: 0.4em 1em;
    border-radius: 4em;
    font-size: 1.6em;
    background: #00000011;
    color: #006666;
    caret-color: #006666;
    outline: #00666600 solid 0;
}

input:focus {
    background: #ffffff;
    outline: #00666644 solid 4px;
}

.box > .i-title {
    text-align: center;
    font-size: 1.6em;
    font-weight: bold;
    color: #666666;
}

.box > .i-label {
    font-size: 1.2em;
    color: #888888;
    margin: 1em 0 0.4em 0.4em;
}

.slider {
    --value: 0;
    border-radius: 4em;
    height: 3.6em;
    background: #00000011;
    cursor: pointer;
    position: relative;
}

.slider::after {
    content: " ";
    position: absolute;
    inset: 0.6em;
    border-radius: 4em;
    width: calc((100% - 3.6em) * var(--value) + 2.4em);
    background: linear-gradient(to right bottom, #73a3ce, #3684c9);
}