/* M07K06 · Speed of light */
.lightspeed-hero{display:grid;grid-template-columns:minmax(0,1.3fr) minmax(320px,.7fr);gap:34px;align-items:center;padding:76px 0 54px;scroll-margin-top:calc(var(--header-h) + 22px)}
.lightspeed-hero>*{min-width:0}.lightspeed-hero-copy :is(h1,h2){margin:12px 0 18px;max-width:940px;font-size:clamp(2.45rem,5vw,4.9rem);line-height:.98;letter-spacing:-.052em}.lightspeed-hero-copy :is(h1,h2) em{color:var(--accent);font-style:normal}.lightspeed-hero-copy>p{margin:0;max-width:850px;color:var(--muted);font-size:1.05rem}.lightspeed-hero-actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:28px}
.lightspeed-hero-card,.lightspeed-card,.lightspeed-note,.lightspeed-panel,.lightspeed-assumption,.lightspeed-reading,.lightspeed-scope-grid article{border:1px solid var(--line);border-radius:var(--radius);background:var(--panel);box-shadow:var(--shadow)}.lightspeed-hero-card{padding:24px}.lightspeed-hero-card>span,.lightspeed-card>span,.lightspeed-reading>span,.lightspeed-scope-grid article>span{color:var(--accent);font-size:.72rem;font-weight:800;letter-spacing:.1em;text-transform:uppercase}.lightspeed-equation{display:grid;place-items:center;min-height:50px;margin:9px 0;padding:10px;border:1px solid var(--line);border-radius:12px;background:color-mix(in srgb,var(--bg-elevated) 78%,transparent);font-family:var(--em-mono);text-align:center;overflow-wrap:anywhere}.lightspeed-equation.large{min-height:68px;font-size:clamp(1rem,1.8vw,1.2rem)}.lightspeed-mini-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:7px;margin-top:9px}.lightspeed-mini-grid div{min-width:0;padding:9px;border:1px solid var(--line);border-radius:11px;background:color-mix(in srgb,var(--panel-solid) 70%,transparent)}.lightspeed-mini-grid span{display:block;color:var(--muted);font-size:.65rem}.lightspeed-mini-grid strong{display:block;margin-top:3px;font-size:.73rem;overflow-wrap:anywhere}
.lightspeed-foundation{padding:42px 0 68px}.lightspeed-foundation-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.lightspeed-card{padding:22px;box-shadow:none}.lightspeed-card.primary{background:color-mix(in srgb,var(--accent) 7%,var(--panel));border-color:color-mix(in srgb,var(--accent) 32%,var(--line))}.lightspeed-card h3{margin:8px 0;font-size:1.08rem}.lightspeed-card p{margin:8px 0 0;color:var(--muted);font-size:.92rem}.lightspeed-note{display:grid;grid-template-columns:230px minmax(0,1fr);gap:18px;align-items:start;margin-top:14px;padding:20px 22px;box-shadow:none}.lightspeed-note strong{color:var(--warm)}.lightspeed-note p{margin:0;color:var(--muted)}
.lightspeed-lab-section{padding:72px 0 64px;border-block:1px solid var(--line);background:color-mix(in srgb,var(--bg-elevated) 38%,transparent)}.lightspeed-lab-shell{display:grid;grid-template-columns:292px minmax(0,1fr);gap:14px;align-items:start}.lightspeed-controls{position:sticky;top:calc(var(--header-h) + 16px);display:grid;gap:13px;padding:18px;border:1px solid var(--line);border-radius:var(--radius);background:color-mix(in srgb,var(--bg-elevated) 92%,transparent);box-shadow:var(--shadow)}.lightspeed-control-head{display:flex;align-items:start;justify-content:space-between;gap:12px;padding-bottom:4px}.lightspeed-control-head>div{display:grid;gap:3px}.lightspeed-control-head span{color:var(--muted);font-size:.72rem}.lightspeed-control-head strong{font-size:.88rem}.lightspeed-status{min-width:max-content;padding:4px 7px;border:1px solid var(--line);border-radius:999px;color:var(--accent)!important;font-weight:800;letter-spacing:.04em}.lightspeed-controls label{min-width:0;display:grid;grid-template-columns:minmax(0,1fr) auto;gap:7px 10px;align-items:center;font-size:.78rem;font-weight:700}.lightspeed-controls label>span{min-width:0}.lightspeed-controls output{color:var(--accent);font-family:var(--em-mono);font-size:.74rem}.lightspeed-controls input[type="range"]{grid-column:1/-1;width:100%;min-width:0;accent-color:var(--accent)}.lightspeed-presets{min-width:0;margin:0;padding:10px;border:1px solid var(--line);border-radius:12px}.lightspeed-presets legend{padding:0 5px;color:var(--muted);font-size:.7rem;font-weight:700}.lightspeed-presets>div{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:5px}.lightspeed-presets button{min-width:0;min-height:36px;padding:5px 6px;border:1px solid var(--line);border-radius:9px;background:var(--panel);color:var(--text);cursor:pointer;font-size:.68rem;font-weight:750}.lightspeed-presets button:hover,.lightspeed-presets button:focus-visible,.lightspeed-presets button.is-active{border-color:color-mix(in srgb,var(--accent) 55%,var(--line));background:color-mix(in srgb,var(--accent) 11%,var(--panel))}.lightspeed-reset{width:100%}.lightspeed-assumption{padding:13px;border-radius:12px;box-shadow:none}.lightspeed-assumption strong{font-size:.76rem}.lightspeed-assumption p{margin:5px 0 0;color:var(--muted);font-size:.71rem;line-height:1.45}
.lightspeed-stage{min-width:0;display:grid;gap:14px}.lightspeed-panel{min-width:0;padding:16px;box-shadow:none;overflow:hidden}.lightspeed-panel-head{display:flex;align-items:start;justify-content:space-between;gap:16px;margin-bottom:10px}.lightspeed-panel-head>div:first-child{display:grid;gap:3px}.lightspeed-panel-head span{color:var(--muted);font-size:.7rem}.lightspeed-panel-head strong{font-size:.88rem}.lightspeed-readout{text-align:right}.lightspeed-readout strong{display:block;color:var(--accent);font-family:var(--em-mono);font-size:.82rem}.lightspeed-map-svg,.lightspeed-flight-svg,.lightspeed-wave-svg{width:100%;overflow:hidden;contain:paint}.lightspeed-detail-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.lightspeed-axis{stroke:var(--line-strong);stroke-width:1.3}.lightspeed-grid{stroke:var(--line);stroke-width:1}.lightspeed-contour{fill:none;stroke:color-mix(in srgb,var(--accent-2) 70%,var(--muted));stroke-width:1.5;stroke-dasharray:5 6}.lightspeed-point{fill:var(--warm);stroke:var(--text);stroke-width:1.5}.lightspeed-label{fill:var(--muted);font-size:14px;font-family:var(--em-mono)}.lightspeed-label.strong{fill:var(--text);font-weight:800}.lightspeed-label.accent{fill:var(--accent)}.lightspeed-label.warm{fill:var(--warm)}.lightspeed-vacuum-line{fill:none;stroke:var(--accent);stroke-width:3}.lightspeed-model-line{fill:none;stroke:var(--warm);stroke-width:3}.lightspeed-marker-vacuum{fill:var(--accent)}.lightspeed-marker-model{fill:var(--warm)}.lightspeed-source,.lightspeed-receiver{fill:var(--panel-solid);stroke:var(--line-strong);stroke-width:2}.lightspeed-metrics,.lightspeed-checks{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px}.lightspeed-metrics div,.lightspeed-checks div{min-width:0;padding:13px 14px;border:1px solid var(--line);border-radius:13px;background:var(--panel)}.lightspeed-metrics span,.lightspeed-checks span{display:block;color:var(--muted);font-size:.69rem}.lightspeed-metrics strong,.lightspeed-checks strong{display:block;margin-top:4px;font-family:var(--em-mono);font-size:.78rem;overflow-wrap:anywhere}.lightspeed-checks strong{color:var(--accent-3)}.lightspeed-reading{padding:18px 20px;box-shadow:none}.lightspeed-reading h3{margin:7px 0 5px;font-size:1rem}.lightspeed-reading p{margin:0;color:var(--muted);font-size:.88rem}.lightspeed-scope{padding:68px 0 46px}.lightspeed-scope-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:10px}.lightspeed-scope-grid article{min-width:0;padding:18px;box-shadow:none}.lightspeed-scope-grid strong{display:block;margin-top:6px}.lightspeed-scope-grid p{margin:7px 0 0;color:var(--muted);font-size:.84rem}
@media(max-width:980px){.lightspeed-hero{grid-template-columns:1fr}.lightspeed-lab-shell{grid-template-columns:1fr}.lightspeed-controls{position:static;grid-template-columns:repeat(2,minmax(0,1fr))}.lightspeed-control-head,.lightspeed-presets,.lightspeed-reset,.lightspeed-assumption{grid-column:1/-1}.lightspeed-scope-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:720px){.lightspeed-hero{padding-top:50px}.lightspeed-hero-copy :is(h1,h2){font-size:clamp(2.1rem,11vw,3.6rem);overflow-wrap:anywhere}.lightspeed-foundation-grid,.lightspeed-detail-grid,.lightspeed-metrics,.lightspeed-checks,.lightspeed-scope-grid{grid-template-columns:1fr}.lightspeed-note{grid-template-columns:1fr}}
@media(max-width:520px){.lightspeed-controls{grid-template-columns:1fr}.lightspeed-control-head,.lightspeed-presets,.lightspeed-reset,.lightspeed-assumption{grid-column:auto}.lightspeed-mini-grid{grid-template-columns:1fr}.lightspeed-panel{padding:12px}.lightspeed-panel-head{flex-direction:column;gap:6px}.lightspeed-readout{text-align:left}.lightspeed-map-svg,.lightspeed-flight-svg,.lightspeed-wave-svg{min-height:260px}}