.gears-lab {
    margin: 1.4rem 0 1.2rem;
    border: 1px solid var(--border);
    border-radius: 1rem;
    background: linear-gradient(165deg, var(--card-top), var(--card-bottom));
    box-shadow: var(--shadow);
    overflow: hidden;
}

.gears-lab-head {
    padding: 1rem 1.1rem .75rem;
    border-bottom: 1px solid var(--border);
}

.gears-lab-head h3 {
    margin: 0 0 .35rem;
    font-size: 1.15rem;
    color: var(--article-strong);
}

.gears-lab-head p {
    margin: 0;
    color: var(--article-byline);
    font-size: .92rem;
}

.gears-lab-body {
    padding: 1rem 1.1rem 1.2rem;
    display: grid;
    gap: 1rem;
}

.gears-toc {
    margin: 0 0 1.4rem;
    padding: .9rem 1rem 1rem;
    border: 1px solid var(--border);
    border-radius: .85rem;
    background: var(--table-surface);
    scroll-margin-top: 5rem;
}

.gears-toc-title {
    display: block;
    margin-bottom: .45rem;
    color: var(--article-strong);
    font-size: .95rem;
}

.gears-toc-list {
    margin: 0;
    padding: 0;
    list-style-position: inside;
    display: grid;
    grid-template-columns: 1fr;
    gap: .15rem .75rem;
}

@media (min-width: 480px) {
    .gears-toc-list {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (min-width: 720px) {
    .gears-toc-list {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}

@media (min-width: 980px) {
    .gears-toc-list {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
}

.gears-toc-list li {
    margin: .15rem 0;
    font-size: .9rem;
    break-inside: avoid;
}

.gears-toc-list a,
.gears-back a {
    color: var(--accent-2, #30d5c8);
    text-decoration: none;
    font-weight: 600;
}

.gears-toc-list a:hover,
.gears-back a:hover { text-decoration: underline; }

.gears-back {
    margin: .65rem 0 0;
    font-size: .85rem;
}

.article h2[id],
#gears-calculator {
    scroll-margin-top: 5rem;
}

.gears-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: .75rem;
}

.gears-field {
    display: grid;
    gap: .3rem;
}

.gears-field label {
    display: block;
    font-size: .82rem;
    font-weight: 700;
    color: var(--article-strong);
    margin-bottom: 0;
}

.gears-field-inputs {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: .45rem;
    align-items: center;
}

.gears-field input[type="number"],
.gears-field select {
    width: 100%;
    border: 1px solid var(--border);
    border-radius: .55rem;
    background: var(--table-surface);
    color: var(--article-text);
    padding: .45rem .6rem;
    font: inherit;
}

.gears-field input[type="number"] {
    width: 5.5rem;
    text-align: center;
}

.gears-field input[type="range"] {
    width: 100%;
    accent-color: var(--accent-2, #30d5c8);
    padding: 0;
}

.gears-photo {
    margin: .85rem 0 1rem;
    border: 1px solid var(--border);
    border-radius: .85rem;
    overflow: hidden;
    background: rgba(0, 0, 0, .22);
}

[data-theme="light"] .gears-photo {
    background: rgba(18, 20, 32, .05);
}

.gears-photo img {
    display: block;
    width: 100%;
    max-width: 420px;
    margin: 0 auto;
    height: auto;
}

.gears-photo p {
    margin: 0;
    padding: .45rem .7rem .55rem;
    font-size: .78rem;
    color: var(--article-byline);
    text-align: center;
}

.gears-photo-grid {
    display: grid;
    gap: .85rem;
    margin: .85rem 0 1rem;
}

@media (min-width: 720px) {
    .gears-photo-grid {
        grid-template-columns: 1fr 1fr;
    }
}

.gears-snapshot {
    margin: 0 0 1.4rem;
    padding: .95rem 1rem 1.05rem;
    border: 1px solid var(--border);
    border-radius: .85rem;
    background: var(--table-surface);
    scroll-margin-top: 5rem;
}

.gears-snapshot-title {
    display: block;
    margin: 0 0 .25rem;
    color: var(--article-strong);
    font-size: 1.05rem;
}

.gears-snapshot-lead {
    margin: 0 0 .85rem;
    color: var(--article-byline);
    font-size: .9rem;
}

.gears-snapshot-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: .65rem;
}

@media (min-width: 560px) {
    .gears-snapshot-grid {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}

@media (min-width: 900px) {
    .gears-snapshot-grid {
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }
}

.gears-snapshot-card {
    display: block;
    text-decoration: none;
    color: inherit;
    border: 1px solid var(--border);
    border-radius: .7rem;
    overflow: hidden;
    background: rgba(0, 0, 0, .22);
    transition: border-color .15s ease, transform .15s ease;
}

[data-theme="light"] .gears-snapshot-card {
    background: rgba(18, 20, 32, .05);
}

.gears-snapshot-card:hover {
    border-color: var(--accent-2, #30d5c8);
    transform: translateY(-1px);
}

.gears-snapshot-card img {
    display: block;
    width: 100%;
    aspect-ratio: 1;
    object-fit: cover;
    height: auto;
}

.gears-snapshot-card span {
    display: block;
    padding: .4rem .5rem .5rem;
    text-align: center;
    font-size: .78rem;
    font-weight: 600;
    color: var(--article-strong);
}

.gears-help {
    border: 1px solid var(--border);
    border-radius: .75rem;
    padding: .75rem .85rem;
    background: var(--table-surface);
}

.gears-help h4 {
    margin: 0 0 .4rem;
    font-size: .95rem;
    color: var(--article-strong);
}

.gears-help p {
    margin: 0 0 .35rem;
    font-size: .86rem;
    color: var(--article-text);
    line-height: 1.45;
}

.gears-help p:last-child { margin-bottom: 0; }

.gears-results {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: .55rem;
}

.gears-stat {
    border: 1px solid var(--border);
    border-radius: .65rem;
    padding: .55rem .65rem;
    background: var(--table-surface);
    text-align: center;
}

.gears-stat .label {
    display: block;
    font-size: .68rem;
    letter-spacing: .04em;
    text-transform: uppercase;
    color: var(--article-byline);
    margin-bottom: .2rem;
}

.gears-stat .value {
    display: block;
    font-size: 1.05rem;
    font-weight: 800;
    color: var(--article-strong);
    font-variant-numeric: tabular-nums;
}

.gears-plots {
    display: grid;
    gap: .85rem;
}

.gears-plot {
    border: 1px solid var(--border);
    border-radius: .85rem;
    background: rgba(0, 0, 0, .22);
    padding: .55rem;
}

[data-theme="light"] .gears-plot {
    background: rgba(18, 20, 32, .05);
}

.gears-plot h4 {
    margin: 0 0 .4rem;
    font-size: .88rem;
    color: var(--article-strong);
}

.gears-plot canvas {
    display: block;
    width: 100%;
    height: 240px;
    border-radius: .45rem;
}

.gears-plot p {
    margin: .4rem 0 0;
    font-size: .78rem;
    color: var(--article-byline);
}

.gears-eq-box {
    border: 1px solid var(--border);
    border-radius: .75rem;
    padding: .7rem .85rem;
    background: var(--table-surface);
}

.gears-eq-box .label {
    display: block;
    font-size: .72rem;
    letter-spacing: .04em;
    text-transform: uppercase;
    color: var(--article-byline);
    margin-bottom: .3rem;
}

.gears-eq-box code {
    display: block;
    font-size: .86rem;
    color: var(--article-strong);
    word-break: break-word;
    line-height: 1.45;
}

.gears-actions {
    display: flex;
    flex-wrap: wrap;
    gap: .55rem;
}

.gears-btn {
    border: 1px solid var(--border);
    border-radius: .65rem;
    background: var(--btn-muted-bg);
    color: var(--btn-muted-text);
    padding: .45rem .85rem;
    font: inherit;
    font-weight: 700;
    cursor: pointer;
}

.gears-btn-primary {
    background: color-mix(in srgb, var(--accent-2) 28%, transparent);
    border-color: color-mix(in srgb, var(--accent-2) 55%, var(--border));
    color: var(--article-strong);
}

.gears-warn {
    margin: 0;
    font-size: .82rem;
    color: var(--article-byline);
}