.qt-sim {
    margin: 3rem 0;
    border: var(--line-width) solid var(--border-color);
    background: var(--bg-primary);
    --sim-zero: var(--text-primary);
    --sim-one: var(--text-secondary);
}
.qt-sim__header { padding: 2rem 2rem 1.5rem; border: 0; transition: none; }
.qt-sim__eyebrow { font-size: .7rem; text-transform: uppercase; letter-spacing: .13em; color: var(--text-secondary); }
.qt-sim__header h2 { font-size: clamp(1.5rem, 3vw, 2.2rem); letter-spacing: -.035em; margin: .65rem 0; }
.qt-sim__header p, .qt-sim__measurements p { font-family: var(--font-serif); color: var(--text-secondary); margin: 0; line-height: 1.65; }
.qt-sim__circuit { display: grid; grid-template-columns: repeat(4, 1fr); list-style: none; padding: 1.25rem 2rem; margin: 0; background: var(--bg-secondary); border-block: 1px solid var(--border-color); }
.qt-sim__circuit li { display: grid; justify-items: center; gap: .5rem; position: relative; text-align: center; }
.qt-sim__circuit li:not(:last-child)::after { content: ''; position: absolute; top: 1.35rem; left: calc(50% + 2.7rem); width: calc(100% - 5.4rem); border-top: 1px solid var(--border-color); }
.qt-sim__circuit b { min-width: 4.5rem; padding: .6rem .4rem; border: 1px solid var(--border-color); background: var(--bg-primary); font: 1rem ui-monospace, monospace; }
.qt-sim__circuit span { font-size: .7rem; color: var(--text-secondary); }
.qt-sim__phase-gate b { color: var(--sim-zero); border-color: var(--sim-zero); }
.qt-sim__phase-gate b span { color: inherit; font-size: inherit; }
.qt-sim__workspace { display: grid; grid-template-columns: minmax(0, 1fr) 240px; }
.qt-sim__figure { margin: 0; min-width: 0; padding: 1.6rem 1.4rem; }
.qt-sim__figure figcaption { font-size: .8rem; font-weight: 600; margin-bottom: 1rem; }
.qt-sim__chart { width: 100%; height: auto; display: block; overflow: visible; }
.qt-sim__grid { fill: none; stroke: var(--border-color); stroke-width: 1; }
.qt-sim__axis { fill: var(--text-secondary); font: 12px ui-monospace, monospace; }
.qt-sim__curve { fill: none; stroke: currentColor; stroke-width: 2.5; }
.qt-sim__zero { color: var(--sim-zero); }
.qt-sim__one { color: var(--sim-one); }
.qt-sim__curve.qt-sim__one { stroke-dasharray: 7 5; }
.qt-sim__cursor { stroke: var(--text-secondary); stroke-width: 1; stroke-dasharray: 3 4; }
.qt-sim__dot { fill: currentColor; stroke: var(--bg-primary); stroke-width: 1.5; }
.qt-sim__legend { display: flex; flex-wrap: wrap; gap: 1.25rem; font-size: .75rem; margin: .75rem 0 1.25rem; }
.qt-sim__insight { margin: 0; font-size: .85rem; line-height: 1.6; min-height: 3.2em; }
.qt-sim__controls { padding: 1.6rem 1.4rem; border-left: 1px solid var(--border-color); }
.qt-sim fieldset { min-width: 0; border: 0; padding: 0; margin: 0; }
.qt-sim__controls legend { font-size: .8rem; font-weight: 600; margin-bottom: 1.5rem; }
.qt-sim__phase-label, .qt-sim__probability { display: flex; align-items: center; justify-content: space-between; gap: .75rem; font-size: .8rem; }
.qt-sim__phase-label output { font: 1.6rem ui-monospace, monospace; }
.qt-sim input[type="range"] { width: 100%; min-height: 44px; margin: .5rem 0 0; accent-color: var(--sim-zero); cursor: pointer; }
.qt-sim__controls p { color: var(--text-secondary); font-size: .7rem; margin: 0 0 1rem; }
.qt-sim button { min-height: 44px; padding: .6rem .8rem; border: 1px solid var(--border-color); background: var(--bg-primary); color: var(--text-primary); font: inherit; font-size: .75rem; cursor: pointer; }
.qt-sim button:hover { background: var(--bg-tertiary); border-color: var(--text-secondary); }
.qt-sim button:focus-visible, .qt-sim input:focus-visible, .qt-sim a:focus-visible { outline: 2px solid var(--sim-zero); outline-offset: 4px; }
.qt-sim button:disabled, .qt-sim fieldset:disabled { opacity: .55; cursor: default; }
.qt-sim__presets { display: grid; grid-template-columns: repeat(3, 1fr); gap: .4rem; }
.qt-sim .qt-sim__play { width: 100%; margin: .65rem 0 1.5rem; }
.qt-sim__play[aria-pressed="true"] { border-color: var(--sim-zero); }
.qt-sim__probability strong { font: 1.2rem ui-monospace, monospace; }
.qt-sim__track { height: 5px; background: var(--bg-tertiary); margin: .6rem 0 1rem; }
.qt-sim__track span { display: block; height: 100%; }
.qt-sim__fill-zero { background: var(--sim-zero); }
.qt-sim__fill-one { background: var(--sim-one); }
.qt-sim__measurements { display: grid; grid-template-columns: 1fr auto; gap: 1rem 1.5rem; padding: 1.5rem 2rem; border-top: 1px solid var(--border-color); }
.qt-sim__measurements h3 { font-size: 1rem; margin: 0 0 .4rem; }
.qt-sim__measurements p { font-size: .85rem; }
.qt-sim__actions { display: flex; gap: .5rem; align-items: center; flex-wrap: wrap; }
.qt-sim [data-measure] { background: var(--text-primary); color: var(--bg-primary); border-color: var(--text-primary); }
.qt-sim [data-measure]:hover { opacity: .85; }
.qt-sim .qt-sim__results { grid-column: 1 / -1; font-family: ui-monospace, monospace; font-size: .75rem; padding-top: 1rem; border-top: 1px solid var(--border-color); color: var(--text-primary); }
.qt-sim__note { font-size: .72rem; line-height: 1.7; padding: 1rem 2rem; margin: 0; border-top: 1px solid var(--border-color); color: var(--text-secondary); background: var(--bg-secondary); transition: none; }
.qt-sim .qt-sim__note a { color: inherit; text-decoration: underline; text-underline-offset: 3px; }
.qt-sim__sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
.qt-sim .qt-sim__browse { display: inline-block; margin-top: 1rem; color: var(--text-primary); font-size: .75rem; text-decoration: underline; text-underline-offset: 4px; }
@media (max-width: 760px) {
    .qt-sim__workspace { grid-template-columns: 1fr; }
    .qt-sim__controls { border-left: 0; border-top: 1px solid var(--border-color); }
    .qt-sim__measurements { grid-template-columns: 1fr; }
    .qt-sim__header, .qt-sim__measurements { padding: 1.25rem; }
    .qt-sim__circuit { padding: 1rem .5rem; }
    .qt-sim__circuit b { min-width: 3.4rem; font-size: .85rem; }
    .qt-sim__circuit li:not(:last-child)::after { left: calc(50% + 1.9rem); width: calc(100% - 3.8rem); }
    .qt-sim__circuit span { font-size: .6rem; }
    .qt-sim__figure { padding: 1.25rem .75rem; }
    .qt-sim__note { padding: 1rem 1.25rem; }
}