:root {
    color-scheme: dark;
    background: #11151b;
    color: #f4efe5;
}

* {
    box-sizing: border-box;
}
html,
body {
    margin: 0;
    min-height: 100%;
}
.shell {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}
.upload {
    position: absolute;
    z-index: 2;
    top: 0.1rem;
    left: 50%;
    transform: translateX(-50%);
    display: inline-flex;
    align-items: center;
    padding: 0.65rem 0.9rem;
    border: 1px solid #4d5662;
    border-radius: 0.2rem;
    background: #252a31;
    color: #f4efe5;
    cursor: pointer;
    font:
        700 0.8rem/1 ui-monospace,
        SFMono-Regular,
        Menlo,
        monospace;
    text-transform: uppercase;
    max-height: 1.5rem;
}
.upload input {
    display: none;
}
.viewer {
    position: relative;
    flex: 1;
    min-height: 100vh;
}
canvas {
    display: block;
    width: 100%;
    height: 100%;
    min-height: 100vh;
}