html, body {
    margin: 0;
    height: 100%;
    background: #000;
    overflow: hidden;
}

/* The canvas backing store is sized to the display in device pixels, so the
   browser never rescales it. The result stays crisp on every screen. */
#screen {
    position: fixed;
    inset: 0;
    width: 100vw;
    height: 100vh;
    display: block;
    background: #000;
}

#boot {
    position: fixed;
    inset: 0;
    z-index: 2;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 18px;
    background: rgba(0, 0, 0, 0.72);
    font-family: system-ui, sans-serif;
    color: #cfcdc7;
}
#boot[hidden] { display: none; }

#checks {
    list-style: none;
    margin: 0;
    padding: 0;
    font-size: 15px;
    letter-spacing: 0.5px;
    color: #8a877f;
}
#checks li { padding: 5px 0; }
#checks li::before { content: "\25CB  "; }
#checks li.ok { color: #7ad07a; }
#checks li.ok::before { content: "\2713  "; }

#loading {
    margin: 0;
    color: #6f6c65;
    font-size: 14px;
}

#start {
    font-family: inherit;
    font-weight: 700;
    font-size: 1.2rem;
    color: #111;
    background: #e8e6e1;
    border: none;
    border-radius: 12px;
    padding: 14px 34px;
    cursor: pointer;
}
#start:hover { background: #fff; }

#hint {
    position: fixed;
    bottom: 14px;
    left: 0;
    right: 0;
    margin: 0;
    z-index: 1;
    text-align: center;
    color: rgba(255, 255, 255, 0.45);
    font-family: system-ui, sans-serif;
    font-size: 13px;
    letter-spacing: 0.5px;
    pointer-events: none;
    user-select: none;
}
#hint[hidden] { display: none; }

/* The source video decodes off-screen. The canvas shows the result. */
#src { display: none; }