/* M04K07 · Total internal reflection */
.tir-hero{display:grid;grid-template-columns:minmax(0,1.16fr) minmax(330px,.84fr);gap:42px;align-items:center;padding-block:88px 74px}.tir-hero-copy{min-width:0}.tir-hero h2{max-width:900px;margin:14px 0 20px;font-size:clamp(2.7rem,5.7vw,5.55rem);line-height:.97;letter-spacing:-.055em}.tir-hero h2 em{font-style:normal;color:var(--accent-3)}.tir-hero-copy>p{max-width:790px;margin:0;color:var(--muted);font-size:1.07rem}.tir-hero-actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:28px}.tir-hero-card{padding:24px;border:1px solid var(--line);border-radius:var(--radius);background:linear-gradient(145deg,color-mix(in srgb,var(--accent-3) 9%,var(--panel)),var(--panel));box-shadow:var(--shadow)}.tir-hero-card>span,.tir-card>span,.tir-field-card>span,.tir-balance-card>span{color:var(--accent-3);font-size:.72rem;font-weight:800;letter-spacing:.09em;text-transform:uppercase}.tir-equation{display:flex;align-items:center;justify-content:center;min-height:72px;margin:14px 0;padding:14px 16px;border:1px solid var(--line);border-radius:16px;background:color-mix(in srgb,var(--bg) 42%,transparent);font-family:"SFMono-Regular",Consolas,"Liberation Mono",monospace;font-weight:700;letter-spacing:-.03em;text-align:center;overflow-wrap:anywhere}.tir-equation.large{min-height:94px;font-size:clamp(1.18rem,2.2vw,1.65rem)}.tir-state-stack{display:grid;gap:8px}.tir-state-stack>div{display:flex;justify-content:space-between;gap:16px;padding:10px 12px;border:1px solid var(--line);border-radius:12px;background:color-mix(in srgb,var(--panel-solid) 64%,transparent)}.tir-state-stack span{color:var(--muted);font-size:.72rem;text-transform:uppercase;letter-spacing:.06em}.tir-state-stack strong{font-size:.78rem;text-align:right}.mono{font-family:"SFMono-Regular",Consolas,"Liberation Mono",monospace}
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var(--line);border-radius:999px;color:var(--muted);font-size:.76rem;font-weight:800}.tir-status.is-propagating{color:var(--accent)}.tir-status.is-critical{color:var(--warm)}.tir-status.is-evanescent{color:var(--accent-3)}.tir-status.is-unavailable{color:var(--muted)}.tir-geometry-svg,.tir-k-svg,.tir-decay-svg{display:block;width:100%;height:auto;border-radius:14px;background:color-mix(in srgb,var(--bg) 54%,transparent)}.tir-panel svg [hidden]{display:none}.tir-interface{stroke:var(--line-strong);stroke-width:2}.tir-normal,.tir-k-axis,.tir-decay-axis{stroke:var(--muted);stroke-width:1.4;stroke-dasharray:7 7;opacity:.72}.tir-medium-text,.tir-axis-text,.tir-k-label,.tir-decay-label{fill:var(--muted);font-size:18px;font-weight:700}.tir-wavefront-i line{stroke:var(--accent);stroke-width:2;opacity:.28}.tir-wavefront-t line{stroke:var(--accent-3);stroke-width:2;opacity:.28}.tir-evanescent 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i{background:var(--warm)}.tir-metrics,.tir-decay-metrics{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;margin-top:12px}.tir-metrics>div,.tir-decay-metrics>div{min-width:0;padding:10px;border:1px solid var(--line);border-radius:12px;background:color-mix(in srgb,var(--bg) 35%,transparent)}.tir-metrics span,.tir-decay-metrics span{display:block;color:var(--muted);font-size:.67rem}.tir-metrics strong,.tir-decay-metrics strong{display:block;margin-top:4px;font-family:"SFMono-Regular",Consolas,"Liberation Mono",monospace;font-size:.84rem;overflow-wrap:anywhere}.tir-detail-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.tir-k-circle{fill:none;stroke:var(--accent-3);stroke-width:2.4}.tir-k-guide{stroke:var(--warm);stroke-width:2;stroke-dasharray:8 7}.tir-k-vector{stroke:var(--accent-3);stroke-width:3.2}.tir-k-point{fill:var(--accent-3)}.tir-k-cross{stroke:var(--warm);stroke-width:3}.tir-decay-curve{fill:none;stroke:var(--accent-3);stroke-width:4}.tir-decay-marker{stroke:var(--warm);stroke-width:2;stroke-dasharray:7 6}.tir-decay-metrics{grid-template-columns:repeat(3,minmax(0,1fr))}.tir-reading p{margin:0;color:var(--muted)}.tir-check{display:flex;justify-content:space-between;gap:16px;margin-top:14px;padding:11px 12px;border:1px solid var(--line);border-radius:12px;background:color-mix(in srgb,var(--bg) 40%,transparent)}.tir-check span{color:var(--muted);font-size:.72rem}.tir-check strong{font-family:"SFMono-Regular",Consolas,"Liberation Mono",monospace;font-size:.78rem;text-align:right}.tir-domain{margin-top:10px!important;font-size:.82rem}.tir-cross-reference{margin-top:26px;color:var(--muted)}.tir-cross-reference a{color:var(--text);text-decoration-color:var(--line-strong)}
@media(max-width:1040px){.tir-hero{grid-template-columns:1fr;gap:24px}.tir-hero-card{max-width:760px}.tir-lab-shell{grid-template-columns:1fr}.tir-controls{position:static;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 18px}.tir-preset-set,.tir-actions,.tir-lab-note{grid-column:1/-1}.tir-transition-grid,.tir-field-grid,.tir-invariant-grid{grid-template-columns:1fr 1fr}.tir-transition-grid>*:last-child,.tir-field-grid>*:last-child,.tir-invariant-grid>*:last-child{grid-column:1/-1}.tir-metrics{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:760px){.tir-hero{padding-block:58px 52px}.tir-hero h2{font-size:clamp(2.35rem,12vw,4rem)}.tir-transition,.tir-field,.tir-invariants,.tir-takeaways{padding-block:58px}.tir-transition-grid,.tir-field-grid,.tir-invariant-grid,.tir-detail-grid{grid-template-columns:1fr}.tir-transition-grid>*:last-child,.tir-field-grid>*:last-child,.tir-invariant-grid>*:last-child{grid-column:auto}.tir-critical-note,.tir-caution,.tir-note{grid-template-columns:1fr;gap:7px}.tir-critical-note strong,.tir-caution strong,.tir-note strong{white-space:normal}.tir-controls{grid-template-columns:1fr}.tir-preset-set,.tir-actions,.tir-lab-note{grid-column:auto}.tir-panel{padding:12px;border-radius:16px}.tir-panel-head{align-items:flex-start;flex-direction:column;gap:8px}.tir-status{align-self:flex-start}.tir-geometry-svg .tir-medium-text,.tir-geometry-svg .tir-axis-text{font-size:36px}.tir-k-svg .tir-axis-text,.tir-k-svg .tir-k-label,.tir-decay-svg .tir-axis-text,.tir-decay-svg .tir-decay-label{font-size:24px}.tir-metrics,.tir-decay-metrics{grid-template-columns:repeat(2,minmax(0,1fr))}.tir-decay-metrics>div:last-child{grid-column:1/-1}.tir-state-stack>div{flex-direction:column;gap:3px}.tir-state-stack strong{text-align:left}.tir-check{flex-direction:column;gap:5px}.tir-check strong{text-align:left}.tir-lab-section{padding-block:58px}}
@media(max-width:390px){.tir-preset-set,.tir-actions{grid-template-columns:1fr}.tir-metrics,.tir-decay-metrics{grid-template-columns:1fr}.tir-decay-metrics>div:last-child{grid-column:auto}}