#frameStack {
    position: fixed;
    top: 46px;
    left: 0;
    width: 100%;
    height: calc(100% - 46px);
    pointer-events: none;
}

.tab-frame {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    border: none;
    display: none;
    background: var(--bg);
    color-scheme: dark;
    pointer-events: auto;
}

.tab-frame.active.visible { display: block; }
.tab-frame.active { display: block; visibility: hidden; }
.tab-frame.active.visible { visibility: visible; }

.tab-strip.visible ~ #frameStack {
    top: 82px;
    height: calc(100% - 82px);
}