/* =========================================================================
   3D model viewer and converter: the hubs, /tools/<format>-viewer and
   /convert/<from>-to-<to>. mt-app* is the tool itself, the rest is the page.
   ========================================================================= */
:root {
    /* Read by includes/navigation-light-landing.html */
    --primary-color: #3b82f6;
    --primary-accent: #2563eb;
    --transition-speed: 0.2s;

    --mt-primary: #2563eb;
    --mt-primary-2: #3b82f6;
    --mt-primary-soft: #eff6ff;
    --mt-ring: rgba(59, 130, 246, 0.25);
    --mt-text: #111827;
    --mt-text-2: #374151;
    --mt-muted: #6b7280;
    --mt-border: #e5e7eb;
    --mt-border-2: #d1d5db;
    --mt-bg: #f5f6f8;
    --mt-card: #fff;
    --mt-ok: #059669;
    --mt-ok-soft: #ecfdf5;
    --mt-warn: #b45309;
    --mt-warn-soft: #fffbeb;
    --mt-bad: #dc2626;
    --mt-bad-soft: #fef2f2;
    --mt-radius: 14px;
    --mt-shadow: 0 1px 2px rgba(17, 24, 39, .05), 0 12px 32px -16px rgba(17, 24, 39, .18);
}

.mt-page { color: var(--mt-text); background: #fff; font-size: 16px; }
.mt-page *, .mt-page *::before, .mt-page *::after { box-sizing: border-box; }
.mt-page section[id] { scroll-margin-top: 88px; }
.mt-wrap { max-width: 1240px; margin: 0 auto; padding: 0 24px; }
.mt-narrow { max-width: 860px; }
.mt-sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.mt-muted { color: var(--mt-muted); }
.mt-small { font-size: 13px; color: var(--mt-muted); line-height: 1.5; margin: 8px 0 0; }
.mt-center { text-align: center; }
.mt-link { color: var(--mt-primary); font-weight: 600; text-decoration: none; }
.mt-link:hover { text-decoration: underline; }
.mt-page a:not(.mt-btn):not(.mt-card):not(.mt-tool):not(.mt-link) { color: var(--mt-primary); }

/* ------------------------------------------------------------------ hero */
.mt-hero {
    padding: 44px 0 22px;
    background:
        radial-gradient(620px 360px at 92% 0%, rgba(59, 130, 246, .14), rgba(59, 130, 246, 0) 70%),
        radial-gradient(460px 320px at 0% 100%, rgba(16, 185, 129, .07), rgba(16, 185, 129, 0) 70%), #fff;
}
.mt-crumbs { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; font-size: 13px; color: var(--mt-muted); margin-bottom: 14px; }
.mt-crumbs a { color: var(--mt-muted); text-decoration: none; }
.mt-crumbs a:hover { color: var(--mt-primary); }
.mt-crumbs [aria-current] { color: var(--mt-text-2); font-weight: 600; }
.mt-h1 { font-size: clamp(30px, 4.2vw, 46px); line-height: 1.08; letter-spacing: -.025em; font-weight: 800; margin: 0 0 12px; color: var(--mt-text); }
.mt-lead { font-size: clamp(16px, 1.5vw, 18.5px); line-height: 1.55; color: var(--mt-text-2); max-width: 820px; margin: 0 0 16px; }
.mt-proof { display: flex; flex-wrap: wrap; gap: 8px 18px; list-style: none; padding: 0; margin: 0; font-size: 14px; color: var(--mt-text-2); }
.mt-proof i { color: var(--mt-ok); margin-right: 4px; }

/* ------------------------------------------------------------- app shell */
.mt-wrap--app { padding-bottom: 8px; }
.mt-app {
    position: relative; display: grid; grid-template-columns: minmax(0, 1fr) 320px;
    height: clamp(560px, calc(100vh - 150px), 860px);
    background: var(--mt-card); border: 1px solid var(--mt-border); border-radius: var(--mt-radius);
    box-shadow: var(--mt-shadow); overflow: hidden;
}
.mt-app.is-drag { outline: 3px dashed var(--mt-primary-2); outline-offset: -6px; }
.mt-app.is-full { height: 100vh; border-radius: 0; }

/* Full-page workspace: once a model is open the viewer covers the window */
html.mt-lock, html.mt-lock body { overflow: hidden !important; overscroll-behavior: none; }
.mt-wsbar { display: none; }
.mt-app.is-workspace {
    position: fixed; inset: 0; z-index: 10000; height: 100vh; height: 100dvh;
    grid-template-columns: minmax(0, 1fr) 340px; grid-template-rows: auto minmax(0, 1fr);
    border: 0; border-radius: 0; box-shadow: none;
}
.mt-app.is-workspace .mt-wsbar {
    grid-column: 1 / -1; display: flex; align-items: center; gap: 12px; min-height: 52px; padding: 8px 12px;
    background: #fff; border-bottom: 1px solid var(--mt-border);
}
.mt-ws-file { flex: 1; min-width: 0; display: flex; align-items: center; gap: 8px; font-size: 14px; white-space: nowrap; }
.mt-ws-file i { color: var(--mt-primary); }
.mt-ws-file strong { min-width: 0; overflow: hidden; text-overflow: ellipsis; color: var(--mt-text); font-weight: 700; }
.mt-ws-file span { flex: none; font-size: 12.5px; color: var(--mt-muted); font-variant-numeric: tabular-nums; }
.mt-ws-actions { flex: none; display: flex; align-items: center; gap: 6px; }
.mt-wsbar .mt-ws-details { display: none; }
.mt-app.is-workspace .mt-chips, .mt-app.is-workspace #btnFull { display: none; }
.mt-app.is-workspace .mt-hint { top: 12px; }
.mt-chip-btn { pointer-events: auto; cursor: pointer; font: inherit; font-size: 12.5px; font-weight: 700; color: var(--mt-primary); }
.mt-chip-btn:hover { border-color: var(--mt-primary-2); background: #fff; }
.mt-stage { position: relative; min-width: 0; min-height: 0; background: radial-gradient(circle at 30% 20%, #fbfcfe 0%, #e3e9f1 85%); overflow: hidden; }
.mt-stage canvas { display: block; width: 100%; height: 100%; touch-action: none; outline: none; }
.mt-app.is-measuring .mt-stage canvas { cursor: crosshair; }

.mt-drop { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; padding: 20px; cursor: pointer; z-index: 3; background: rgba(238, 242, 247, .55); backdrop-filter: blur(1px); }
.mt-drop[hidden] { display: none; }
.mt-app.is-drag .mt-drop { display: flex !important; }
.mt-drop-card {
    width: min(460px, 100%); text-align: center; padding: 30px 26px 24px;
    background: #fff; border: 2px dashed #c7d2fe; border-radius: 18px; box-shadow: var(--mt-shadow);
    transition: border-color .15s, transform .15s;
}
.mt-drop:hover .mt-drop-card, .mt-app.is-drag .mt-drop-card { border-color: var(--mt-primary-2); transform: translateY(-1px); }
.mt-drop-icon { width: 58px; height: 58px; margin: 0 auto 12px; border-radius: 16px; display: grid; place-items: center; font-size: 24px; color: var(--mt-primary); background: var(--mt-primary-soft); }
.mt-drop-title { font-size: 19px; font-weight: 750; margin: 0 0 2px; color: var(--mt-text); }
.mt-drop-sub { margin: 0 0 14px; color: var(--mt-muted); font-size: 14px; }
.mt-drop-actions { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px; margin-bottom: 14px; }
.mt-drop-formats { font-size: 12px; letter-spacing: .02em; color: var(--mt-muted); margin: 0 0 6px; }
.mt-drop-privacy { font-size: 12.5px; color: var(--mt-ok); margin: 0; font-weight: 600; }

.mt-btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 7px;
    padding: 10px 16px; border-radius: 10px; border: 1px solid var(--mt-border-2); background: #fff; color: var(--mt-text);
    font: 600 14px/1.2 inherit; cursor: pointer; text-decoration: none; transition: background .15s, border-color .15s, box-shadow .15s;
}
.mt-btn:hover { background: #f9fafb; border-color: #9ca3af; }
.mt-btn:focus-visible, .mt-tb:focus-visible, .mt-fmt:focus-visible { outline: none; box-shadow: 0 0 0 3px var(--mt-ring); }
.mt-btn:disabled { opacity: .5; cursor: not-allowed; }
.mt-btn-primary { background: var(--mt-primary); border-color: var(--mt-primary); color: #fff; }
.mt-btn-primary:hover { background: #1d4ed8; border-color: #1d4ed8; color: #fff; }
.mt-btn-sm { padding: 6px 10px; font-size: 13px; border-radius: 8px; }
.mt-btn-lg { width: 100%; padding: 14px 18px; font-size: 16px; border-radius: 12px; }
.mt-btn-warn { background: var(--mt-warn-soft); border-color: #fcd34d; color: var(--mt-warn); margin-top: 10px; }
.mt-btn-ghost { border-color: transparent; color: var(--mt-muted); }

.mt-loading { position: absolute; inset: 0; z-index: 5; display: flex; flex-direction: column; gap: 12px; align-items: center; justify-content: center; background: rgba(255, 255, 255, .72); }
.mt-loading[hidden] { display: none; }
.mt-loading p { margin: 0; font-size: 14px; font-weight: 600; color: var(--mt-text-2); text-align: center; padding: 0 20px; }
.mt-spinner { width: 38px; height: 38px; border-radius: 50%; border: 3px solid #dbeafe; border-top-color: var(--mt-primary); animation: mt-spin .8s linear infinite; }
@keyframes mt-spin { to { transform: rotate(360deg); } }

.mt-chips, .mt-conv-info { position: absolute; top: 12px; left: 12px; right: 12px; display: flex; flex-wrap: wrap; gap: 6px; z-index: 2; pointer-events: none; }
.mt-chips[hidden], .mt-conv-info[hidden] { display: none; }
.mt-chip { display: inline-flex; align-items: center; gap: 6px; max-width: 100%; padding: 5px 10px; border-radius: 999px; background: rgba(255, 255, 255, .92); border: 1px solid var(--mt-border); font-size: 12.5px; font-weight: 600; color: var(--mt-text-2); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.mt-hint { position: absolute; top: 48px; left: 12px; right: 12px; z-index: 4; display: flex; flex-wrap: wrap; align-items: center; gap: 8px 10px; padding: 10px 36px 10px 12px; border-radius: 10px; background: var(--mt-warn-soft); border: 1px solid #fcd34d; color: #78350f; font-size: 13.5px; }
.mt-hint[hidden] { display: none; }
.mt-hint-x { position: absolute; right: 8px; top: 6px; border: 0; background: none; font-size: 20px; line-height: 1; color: #92400e; cursor: pointer; }

.mt-toolbar { position: absolute; left: 50%; bottom: 14px; transform: translateX(-50%); z-index: 2; display: flex; align-items: center; gap: 2px; padding: 5px; border-radius: 14px; background: rgba(255, 255, 255, .95); border: 1px solid var(--mt-border); box-shadow: var(--mt-shadow); width: max-content; max-width: calc(100% - 24px); flex-wrap: wrap; justify-content: center; }
.mt-toolbar[hidden] { display: none; }
.mt-toolbar--mini { left: auto; right: 12px; transform: none; bottom: 12px; }
.mt-tb { width: 36px; height: 36px; border: 0; border-radius: 9px; background: transparent; color: var(--mt-text-2); font-size: 15px; cursor: pointer; display: grid; place-items: center; }
.mt-tb:hover { background: #f3f4f6; }
.mt-tb.is-on { background: var(--mt-primary-soft); color: var(--mt-primary); }
.mt-tb:disabled { opacity: .4; cursor: default; }
.mt-tb-txt { font-weight: 800; font-size: 13px; }
.mt-tb-sep { width: 1px; height: 22px; background: var(--mt-border); margin: 0 4px; }

.mt-measure { position: absolute; left: 12px; bottom: 70px; z-index: 2; padding: 8px 12px; border-radius: 10px; background: #111827; color: #fff; font-size: 13px; font-weight: 600; font-variant-numeric: tabular-nums; max-width: calc(100% - 24px); }
.mt-measure[hidden] { display: none; }
.mt-measure-label { position: absolute; left: 0; top: 0; z-index: 2; padding: 3px 8px; border-radius: 6px; background: #ef4444; color: #fff; font-size: 12px; font-weight: 700; pointer-events: none; white-space: nowrap; }
.mt-measure-label[hidden] { display: none; }
.mt-slice { position: absolute; right: 12px; top: 50%; transform: translateY(-50%); z-index: 2; display: flex; flex-direction: column; align-items: center; gap: 8px; padding: 10px 8px; border-radius: 12px; background: rgba(255, 255, 255, .95); border: 1px solid var(--mt-border); }
.mt-slice[hidden] { display: none; }
.mt-slice label { font-size: 11px; font-weight: 700; color: var(--mt-text-2); text-align: center; width: 70px; }
.mt-slice input[type=range] { writing-mode: vertical-lr; direction: rtl; height: 180px; width: 22px; accent-color: var(--mt-primary); }
.mt-section { padding: 64px 0; }
.mt-section--alt { background: var(--mt-bg); }

/* sidebar */
.mt-side { border-left: 1px solid var(--mt-border); overflow-y: auto; background: #fff; font-size: 14px; overscroll-behavior: contain; }
.mt-sec { padding: 14px 16px; border-bottom: 1px solid #f0f1f3; }
.mt-sec:last-child { border-bottom: 0; }
.mt-sec-title { display: flex; align-items: center; justify-content: space-between; font-size: 11.5px; font-weight: 800; letter-spacing: .07em; text-transform: uppercase; color: var(--mt-muted); margin-bottom: 8px; }
.mt-dl { margin: 0; display: grid; gap: 4px; }
.mt-dl > div { display: flex; justify-content: space-between; gap: 10px; }
.mt-dl dt { color: var(--mt-muted); font-weight: 500; }
.mt-dl dd { margin: 0; font-weight: 650; text-align: right; color: var(--mt-text); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; max-width: 62%; font-variant-numeric: tabular-nums; }
.mt-notes { list-style: none; padding: 0; margin: 8px 0 0; display: grid; gap: 6px; }
.mt-notes:empty { display: none; }
.mt-notes li { font-size: 12.5px; line-height: 1.45; padding: 7px 9px; border-radius: 8px; background: var(--mt-primary-soft); color: #1e3a8a; }
.mt-dims { display: grid; gap: 6px; margin-bottom: 10px; }
.mt-dim { display: grid; grid-template-columns: 16px 1fr auto; align-items: center; gap: 8px; }
.mt-ax { font-weight: 800; font-size: 12px; }
.mt-ax-x { color: #ef4444; } .mt-ax-y { color: #22c55e; } .mt-ax-z { color: #3b82f6; }
.mt-dim-track { height: 6px; border-radius: 4px; background: #f1f3f6; overflow: hidden; }
.mt-dim-bar { display: block; height: 100%; width: 0; border-radius: 4px; background: currentColor; transition: width .3s; }
.mt-dim-val { font-weight: 700; font-variant-numeric: tabular-nums; min-width: 78px; text-align: right; }
.mt-field { display: grid; gap: 4px; margin-top: 10px; min-width: 0; }
.mt-field label { font-size: 12px; font-weight: 600; color: var(--mt-muted); }
.mt-field select, .mt-field input { width: 100%; padding: 8px 10px; border: 1px solid var(--mt-border-2); border-radius: 8px; background: #fff; font: inherit; font-size: 14px; color: var(--mt-text); }
.mt-field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.mt-field-row .mt-field { margin-top: 10px; }
.mt-units { display: inline-flex; border: 1px solid var(--mt-border-2); border-radius: 7px; overflow: hidden; text-transform: none; letter-spacing: 0; }
.mt-units button { border: 0; background: #fff; padding: 2px 8px; font-size: 11.5px; font-weight: 700; color: var(--mt-muted); cursor: pointer; }
.mt-units button.active { background: var(--mt-primary); color: #fff; }
.mt-fit { margin: 10px 0 0; font-size: 13px; line-height: 1.45; color: var(--mt-muted); }
.mt-fit.is-ok { color: var(--mt-ok); font-weight: 600; }
.mt-fit.is-warn { color: var(--mt-warn); font-weight: 600; }
.mt-fit.is-bad { color: var(--mt-bad); font-weight: 600; }
.mt-check-sum { margin: 0 0 8px; font-size: 13px; line-height: 1.45; font-weight: 600; color: var(--mt-muted); }
.mt-check-sum.is-ok { color: var(--mt-ok); }
.mt-check-sum.is-warn { color: var(--mt-warn); }
.mt-check { list-style: none; padding: 0; margin: 0; display: grid; gap: 3px; }
.mt-check li { display: flex; justify-content: space-between; gap: 8px; font-size: 13px; padding: 3px 0; }
.mt-check li span { color: var(--mt-text-2); }
.mt-check li.is-ok strong { color: var(--mt-ok); }
.mt-check li.is-bad strong { color: var(--mt-bad); }
.mt-check li.is-warn strong { color: var(--mt-warn); }
.mt-check li.is-info strong { color: var(--mt-text); }
.mt-fmt-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 6px; }
.mt-fmt { display: flex; flex-direction: column; align-items: center; gap: 1px; padding: 8px 4px; border: 1px solid var(--mt-border-2); border-radius: 10px; background: #fff; cursor: pointer; color: var(--mt-text); transition: border-color .15s, background .15s; }
.mt-fmt b { font-size: 14px; }
.mt-fmt small { font-size: 10.5px; color: var(--mt-muted); white-space: nowrap; }
.mt-fmt:hover:not(:disabled) { border-color: var(--mt-primary-2); background: var(--mt-primary-soft); }
.mt-fmt:disabled { opacity: .45; cursor: not-allowed; }
.mt-fmt.is-on { border-color: var(--mt-primary); background: var(--mt-primary-soft); box-shadow: inset 0 0 0 1px var(--mt-primary); }
.mt-fmt.is-on b { color: var(--mt-primary); }
.mt-color { display: flex; align-items: center; justify-content: space-between; gap: 8px; font-size: 13px; color: var(--mt-text-2); }
.mt-color input { width: 34px; height: 26px; padding: 0; border: 1px solid var(--mt-border-2); border-radius: 6px; background: none; cursor: pointer; }

.mt-toast { position: fixed; left: 50%; bottom: 24px; z-index: 10010; transform: translate(-50%, 20px); opacity: 0; pointer-events: none; max-width: min(560px, calc(100% - 32px)); padding: 12px 16px; border-radius: 12px; background: #111827; color: #fff; font-size: 14px; line-height: 1.45; box-shadow: var(--mt-shadow); transition: opacity .2s, transform .2s; }
.mt-toast.is-on { opacity: 1; transform: translate(-50%, 0); }
.mt-toast.is-error { background: #991b1b; }

/* converter */
.mt-converter { grid-template-columns: minmax(0, 1fr) 340px; }
.mt-conv-main { display: grid; grid-template-rows: minmax(0, 1fr) auto; min-width: 0; min-height: 0; }
.mt-queue-wrap { border-top: 1px solid var(--mt-border); background: #fff; max-height: 220px; overflow-y: auto; display: none; }
.mt-converter.has-files .mt-queue-wrap { display: block; }
.mt-queue { list-style: none; padding: 6px; margin: 0; display: grid; gap: 4px; }
.mt-job { display: grid; grid-template-columns: minmax(0, 1fr) auto auto auto; align-items: center; gap: 10px; padding: 6px 8px; border-radius: 10px; border: 1px solid transparent; }
.mt-job.is-selected { background: var(--mt-primary-soft); border-color: #bfdbfe; }
.mt-job-name { min-width: 0; border: 0; background: none; text-align: left; font: 600 14px/1.3 inherit; color: var(--mt-text); cursor: pointer; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; padding: 4px 0; }
.mt-job-meta { font-size: 12.5px; color: var(--mt-muted); white-space: nowrap; font-variant-numeric: tabular-nums; }
.mt-job.is-done .mt-job-meta { color: var(--mt-ok); font-weight: 600; }
.mt-job.is-error .mt-job-meta { color: var(--mt-bad); white-space: normal; max-width: 260px; }
.mt-job.is-working .mt-job-meta { color: var(--mt-primary); }
.mt-job-x { border: 0; background: none; font-size: 18px; color: var(--mt-muted); cursor: pointer; padding: 0 4px; }
.mt-queue-actions { display: flex; flex-wrap: wrap; gap: 6px; padding: 0 12px 10px; }
.mt-keeps { margin: 10px 0 0; font-size: 13px; line-height: 1.45; color: var(--mt-text-2); }
.mt-warn { list-style: none; padding: 0; margin: 8px 0 0; display: grid; gap: 6px; }
.mt-warn[hidden] { display: none; }
.mt-warn li { font-size: 12.5px; line-height: 1.45; padding: 7px 9px; border-radius: 8px; background: var(--mt-warn-soft); color: #78350f; }
.mt-check-row { display: flex; align-items: flex-start; gap: 8px; font-size: 13.5px; color: var(--mt-text-2); margin: 4px 0; cursor: pointer; }
.mt-check-row input { margin-top: 3px; accent-color: var(--mt-primary); }
.mt-adv { margin-top: 12px; border: 1px solid var(--mt-border); border-radius: 10px; padding: 8px 12px 12px; }
.mt-adv summary { cursor: pointer; font-size: 13.5px; font-weight: 700; color: var(--mt-text-2); padding: 2px 0; }
.mt-adv .mt-units { margin-top: 12px; }
.mt-sec--go { position: sticky; bottom: 0; background: #fff; border-top: 1px solid var(--mt-border); }
.mt-result { margin: 10px 0 0; font-size: 13.5px; color: var(--mt-ok); font-weight: 600; line-height: 1.45; }
.mt-result[hidden] { display: none; }

/* ---------------------------------------------------------------- page */
.mt-h2 { font-size: clamp(24px, 2.6vw, 32px); line-height: 1.18; letter-spacing: -.02em; font-weight: 800; margin: 0 0 14px; color: var(--mt-text); }
.mt-h3 { font-size: 18px; font-weight: 750; margin: 36px 0 12px; }
.mt-sub { color: var(--mt-muted); max-width: 780px; margin: 0 0 22px; line-height: 1.55; }
.mt-steps { list-style: none; padding: 0; margin: 22px 0 0; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 16px; }
.mt-steps li { display: flex; gap: 12px; padding: 18px; border: 1px solid var(--mt-border); border-radius: var(--mt-radius); background: #fff; }
.mt-step-n { flex: none; width: 30px; height: 30px; border-radius: 50%; display: grid; place-items: center; background: var(--mt-primary-soft); color: var(--mt-primary); font-weight: 800; font-size: 14px; }
.mt-steps h3 { font-size: 16px; margin: 3px 0 6px; font-weight: 750; }
.mt-steps p { margin: 0; font-size: 14.5px; line-height: 1.55; color: var(--mt-text-2); }
.mt-table { width: 100%; border-collapse: collapse; background: #fff; border: 1px solid var(--mt-border); border-radius: var(--mt-radius); overflow: hidden; font-size: 15px; }
.mt-table th, .mt-table td { padding: 12px 14px; border-bottom: 1px solid #f0f1f3; text-align: left; vertical-align: top; line-height: 1.5; }
.mt-table tr:last-child th, .mt-table tr:last-child td { border-bottom: 0; }
.mt-table thead th { background: #f9fafb; font-size: 12.5px; text-transform: uppercase; letter-spacing: .05em; color: var(--mt-muted); }
.mt-carry th { width: 150px; font-weight: 750; color: var(--mt-text); }
.mt-carry td i { margin-right: 6px; }
.mt-carry tr.is-ok td i { color: var(--mt-ok); }
.mt-carry tr.is-warn td i { color: #d97706; }
.mt-carry tr.is-lost td i { color: var(--mt-bad); }
.mt-carry tr.is-info td i { color: var(--mt-primary-2); }
.mt-table--compact { font-size: 13.5px; }
.mt-table--compact th, .mt-table--compact td { padding: 7px 10px; }
.mt-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; }
.mt-matrix { min-width: 760px; font-size: 13.5px; }
.mt-matrix td, .mt-matrix th { text-align: center; white-space: nowrap; }
.mt-matrix tbody th { text-align: left; }
.mt-matrix a { font-weight: 650; text-decoration: none; }
.mt-ticks { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px 28px; }
.mt-ticks li { display: flex; gap: 10px; line-height: 1.5; color: var(--mt-text-2); }
.mt-ticks i { color: var(--mt-ok); margin-top: 4px; }
.mt-cols { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr); gap: 44px; align-items: start; }
.mt-prose p { font-size: 16.5px; line-height: 1.7; color: var(--mt-text-2); margin: 0 0 16px; }
.mt-prose code, .mt-tip code, .mt-faq code { background: #f3f4f6; padding: 1px 5px; border-radius: 5px; font-size: .9em; }
.mt-facts { display: grid; gap: 16px; }
.mt-fact-card { border: 1px solid var(--mt-border); border-radius: var(--mt-radius); padding: 18px; background: #fff; box-shadow: var(--mt-shadow); }
.mt-fact-card h3 { font-size: 17px; margin: 0 0 2px; font-weight: 800; }
.mt-fact-long { font-size: 13px; color: var(--mt-muted); margin: 0 0 12px; }
.mt-fact-card dl { margin: 0 0 12px; display: grid; gap: 7px; }
.mt-fact-card dl > div { display: grid; grid-template-columns: 96px 1fr; gap: 10px; font-size: 14px; line-height: 1.45; }
.mt-fact-card dt { color: var(--mt-muted); font-weight: 600; }
.mt-fact-card dd { margin: 0; color: var(--mt-text-2); }
.mt-fact-about { font-size: 14px; line-height: 1.6; color: var(--mt-text-2); margin: 0 0 10px; }
.mt-tips { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.mt-tip { padding: 18px; border-radius: var(--mt-radius); background: #fff; border: 1px solid var(--mt-border); }
.mt-tip h3 { font-size: 16px; margin: 0 0 6px; font-weight: 750; }
.mt-tip p { margin: 0; font-size: 14.5px; line-height: 1.6; color: var(--mt-text-2); }
.mt-faq details { border: 1px solid var(--mt-border); border-radius: 12px; background: #fff; margin-bottom: 10px; }
.mt-faq summary { list-style: none; cursor: pointer; padding: 16px 44px 16px 18px; position: relative; }
.mt-faq summary::-webkit-details-marker { display: none; }
.mt-faq summary::after { content: '+'; position: absolute; right: 18px; top: 12px; font-size: 22px; color: var(--mt-muted); }
.mt-faq details[open] summary::after { content: '−'; }
.mt-faq summary h3 { margin: 0; font-size: 16.5px; font-weight: 700; line-height: 1.4; }
.mt-faq-a { padding: 0 18px 16px; font-size: 15.5px; line-height: 1.65; color: var(--mt-text-2); }
.mt-cards { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; }
.mt-card { display: flex; flex-direction: column; gap: 6px; padding: 16px; border: 1px solid var(--mt-border); border-radius: var(--mt-radius); background: #fff; text-decoration: none; color: var(--mt-text); transition: border-color .15s, box-shadow .15s, transform .15s; }
.mt-card:hover { border-color: #93c5fd; box-shadow: var(--mt-shadow); transform: translateY(-1px); color: var(--mt-text); }
.mt-card h3 { font-size: 15.5px; margin: 0; font-weight: 750; }
.mt-card p { font-size: 13.5px; margin: 0; color: var(--mt-muted); line-height: 1.5; }
.mt-card-tag { align-self: flex-start; font-size: 11px; font-weight: 800; letter-spacing: .06em; text-transform: uppercase; padding: 3px 8px; border-radius: 999px; background: var(--mt-primary-soft); color: var(--mt-primary); }
.mt-pair { display: inline-flex; align-items: center; gap: 6px; font-size: 12px; color: var(--mt-muted); }
.mt-pair b { padding: 2px 7px; border-radius: 6px; background: #f3f4f6; color: var(--mt-text-2); font-size: 11.5px; }
.mt-pair b:last-child { background: var(--mt-primary-soft); color: var(--mt-primary); }
.mt-cards--small .mt-card { padding: 12px 14px; }
.mt-tools { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; }
.mt-tool { display: flex; flex-direction: column; gap: 2px; padding: 12px 14px; border-radius: 12px; border: 1px solid var(--mt-border); text-decoration: none; color: var(--mt-text); background: #fff; }
.mt-tool:hover { border-color: #93c5fd; color: var(--mt-text); }
.mt-tool strong { font-size: 14.5px; }
.mt-tool span { font-size: 13px; color: var(--mt-muted); }
.mt-updated { margin: 28px 0 0; font-size: 13px; color: var(--mt-muted); }

/* ------------------------------------------------------------ responsive */
@media (max-width: 1100px) {
    .mt-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .mt-cards { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}
@media (max-width: 900px) {
    .mt-app, .mt-converter { grid-template-columns: minmax(0, 1fr); height: auto; }
    .mt-stage { height: min(68vh, 520px); }
    .mt-conv-main { grid-template-rows: auto auto; }
    .mt-side { border-left: 0; border-top: 1px solid var(--mt-border); overflow: visible; }
    .mt-viewer .mt-side { display: grid; grid-template-columns: 1fr 1fr; }
    .mt-viewer .mt-sec { border-right: 1px solid #f0f1f3; }
    .mt-sec--go { position: static; }
    .mt-cols { grid-template-columns: minmax(0, 1fr); gap: 28px; }
    .mt-tips, .mt-tools { grid-template-columns: minmax(0, 1fr); }
    .mt-cards { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .mt-ticks { grid-template-columns: minmax(0, 1fr); }
    .mt-app.is-full .mt-stage { height: 100vh; }
    .mt-app.is-workspace { grid-template-columns: minmax(0, 1fr); }
    .mt-app.is-workspace .mt-stage, .mt-app.is-workspace.is-full .mt-stage { height: auto; }
    .mt-app.is-workspace .mt-wsbar .mt-ws-details { display: inline-flex; }
    .mt-app.is-workspace.side-open .mt-ws-details { background: var(--mt-primary-soft); border-color: var(--mt-primary-2); color: var(--mt-primary); }
    .mt-app.is-workspace .mt-side {
        position: absolute; left: 0; right: 0; bottom: 0; z-index: 6; max-height: min(62%, 560px); overflow-y: auto;
        border-top: 1px solid var(--mt-border); border-radius: 16px 16px 0 0; box-shadow: 0 -16px 40px -16px rgba(17, 24, 39, .35);
        transform: translateY(calc(100% + 24px)); visibility: hidden; transition: transform .25s ease, visibility 0s linear .25s;
    }
    .mt-app.is-workspace.side-open .mt-side { transform: none; visibility: visible; transition: transform .25s ease; }
}
@media (max-width: 600px) {
    .mt-wrap { padding: 0 14px; }
    .mt-hero { padding: 32px 0 16px; }
    .mt-viewer .mt-side { grid-template-columns: minmax(0, 1fr); }
    .mt-steps { grid-template-columns: minmax(0, 1fr); }
    .mt-cards { grid-template-columns: minmax(0, 1fr); }
    .mt-section { padding: 44px 0; }
    .mt-tb { width: 34px; height: 34px; flex: none; }
    .mt-tb-sep { display: none; }
    .mt-toolbar { flex-wrap: nowrap; overflow-x: auto; justify-content: flex-start; max-width: calc(100% - 16px); bottom: 8px; scrollbar-width: none; }
    .mt-toolbar--mini { max-width: none; }
    .mt-measure { bottom: 58px; }
    .mt-job { grid-template-columns: minmax(0, 1fr) auto auto; }
    .mt-job .mt-job-meta { grid-column: 1 / -1; grid-row: 2; }
    .mt-carry th { width: 96px; }
    .mt-app.is-workspace .mt-wsbar { gap: 8px; padding: 6px 8px; }
    .mt-wsbar .mt-ws-lbl, .mt-ws-file span { display: none; }
}
@media (prefers-reduced-motion: reduce) {
    .mt-spinner { animation-duration: 2s; }
    .mt-card, .mt-drop-card, .mt-dim-bar, .mt-app.is-workspace .mt-side { transition: none !important; }
}