#mechanism-svg:has(.isp-origin),#mechanism-svg:has(.ray-lesson){display:block;aspect-ratio:auto}.ray-lesson{width:100%}
.site-header nav{display:flex;gap:8px}.site-header [data-open-glossary]{background:#0865cf;color:#fff;border-color:#0865cf}
.aperture-coupling{grid-column:1/-1;border:1px solid #a6b4c4;border-left:4px solid #0865cf;padding:13px;background:#fff}.aperture-choice{display:flex;gap:6px;align-items:center;flex-wrap:wrap;font-size:12px}.aperture-choice button,.ray-point-picker button{font-size:12px;padding:7px 10px}.aperture-choice button[aria-pressed=true],.ray-point-picker button[aria-pressed=true]{background:#143852;color:white;border-color:#143852}.aperture-equation{display:flex;flex-wrap:wrap;justify-content:space-between;gap:6px;font-size:13px;margin-top:13px}.aperture-coupling p{font-size:12px;line-height:1.6;margin:8px 0}.aperture-coupling .term-button{font-size:12px}.aperture-limit{color:#8b5000}.optical-scale{display:flex;align-items:center;flex-wrap:wrap;gap:9px;padding:10px 15px;border-bottom:1px solid #b4c0ce;background:#f2f4f6;font-size:12px}.optical-scale label{display:flex;align-items:center;gap:7px}.optical-scale select{padding:6px;background:white;border:1px solid #a7b5c5;color:#173047}.optical-scale button{padding:7px 10px;font-size:12px}.optical-scale p{width:100%;color:#8b5000;margin:0}.optical-scale[hidden]{display:none}.ray-point-picker{display:flex;flex-wrap:wrap;align-items:center;gap:6px;padding:4px 16px 12px;font-size:12px}.ray-point-picker [data-ray-point]:not([data-ray-point=all]){border-bottom:3px solid var(--point-color)}.ray-reading{display:grid;grid-template-columns:1fr 1fr;gap:16px;border-top:1px solid #c4ccd6;padding:12px 20px}.ray-reading p{font-size:13px;line-height:1.65;margin:0}.ray-reading b{color:#173047}@media(max-width:600px){.ray-reading{grid-template-columns:1fr}.aperture-equation{flex-direction:column}.optical-scale span{width:100%}.ray-point-picker{gap:4px;padding:4px 10px 10px}}
.reader.glossary-reader{width:min(510px,calc(100vw - 32px))}.reader-navigation{display:flex;gap:8px;padding:9px 16px;border-bottom:1px solid #c5cbd2;background:#f4f5f6}.reader-navigation button{font-size:12px;padding:7px 10px}.reader-navigation [hidden]{display:none}
.glossary-intro{margin-top:0}.glossary-search{display:block;font-weight:650;font-size:13px}.glossary-search input{width:100%;display:block;margin-top:6px;padding:12px;border:1px solid #8996a5;border-radius:2px;background:#fff;color:#172332;font:inherit;font-size:15px}
.reading-equation{margin:18px 0 12px;padding:13px 14px;border:1px solid #c4cdd7;border-left:3px solid #0865cf;background:#f5f7fa;overflow-x:auto}.reading-equation>span{display:block;font-size:12px;color:#526277;line-height:1.5;margin-bottom:10px}.reading-equation math{font-size:20px;margin:0;text-align:left;math-style:normal}.symbol-definitions{display:grid;grid-template-columns:minmax(45px,auto) minmax(0,1fr);gap:8px 12px;padding:0 0 15px;margin:14px 0 18px;border-bottom:1px solid #d2d8df;font-size:13px;line-height:1.65}.symbol-definitions dt{font-family:Georgia,serif;font-style:italic;font-weight:700;color:#193a59;white-space:nowrap}.symbol-definitions dd{margin:0;color:#435367}.term-technical>p{margin:15px 0;line-height:1.8}.formula-assumptions{font-size:13px;border-top:1px solid #c5cbd2;padding:12px 0;margin:18px 0}.formula-assumptions summary{cursor:pointer;font-weight:650}.reader-body>math{display:block math;padding:16px 6px;margin:18px 0;border-bottom:1px solid #d4dce5;overflow-x:auto;font-size:20px}
.glossary-categories{display:flex;gap:5px;flex-wrap:wrap;margin:13px 0}.glossary-categories button{padding:7px 9px;font-size:12px}.glossary-categories button[aria-pressed=true]{color:#fff;background:#202e40;border-color:#202e40}
.glossary-shortcuts{display:flex;gap:5px;flex-wrap:wrap;border-bottom:1px solid #c5cbd2;padding-bottom:15px}.glossary-shortcuts span{width:100%;font-size:12px;color:#536274}.glossary-shortcuts button{font-size:12px;padding:5px 8px;border:0;border-bottom:1px solid #0865cf;color:#0754aa;background:transparent}
.glossary-count{font-size:12px;color:#526171;margin:14px 0}.glossary-list{list-style:none;padding:0!important;margin:0!important}.glossary-list li{margin:0!important;border-bottom:1px solid #d3d8de}.glossary-list button{display:block;width:100%;text-align:left;padding:13px 9px;background:#fff;border:0;border-radius:0}.glossary-list button:hover{background:#f0f4f9}.glossary-list strong{display:block;color:#152b43;font-size:16px}.glossary-list span{display:block;font-size:13px;line-height:1.55;margin:5px 0;color:#435267;font-weight:400}.glossary-list small{font-size:10px;text-transform:uppercase;letter-spacing:.08em;color:#647284}
.term-english{font-size:12px;color:#657385;margin-top:0}.term-definition{font-size:18px;line-height:1.65;color:#172b43;font-weight:550}.term-example{padding:14px 16px;border-left:3px solid #0865cf;background:#f1f5f9}.term-example h3{font-size:12px;text-transform:uppercase;letter-spacing:.06em;margin:0 0 7px}.term-example p{margin:0}.term-distinction{border-left:3px solid #b36b00;padding-left:13px;font-size:13px}.term-technical{margin:20px 0;border-top:1px solid #c5cbd2;border-bottom:1px solid #c5cbd2;padding:13px 0}.term-technical summary{font-weight:650;cursor:pointer}.term-technical h4{font-size:13px;margin-bottom:4px}.term-technical [data-live-term]{font-size:13px;background:#f1f5f9;padding:12px}.term-related h3{font-size:13px}.term-related button{margin:0 5px 7px 0;font-size:12px;padding:6px 9px}.term-routes{display:flex;gap:7px;flex-wrap:wrap;margin:15px 0}.term-routes button{font-size:12px}.term-sources{font-size:12px;margin:18px 0}.term-sources summary{cursor:pointer}.term-sources a{display:block;margin-top:10px}
.bit-demo{margin:20px 0;border:1px solid #b5c0cd;padding:12px}.bit-demo h3{font-size:15px;margin:0 0 12px}.bit-demo label{font-size:13px;display:flex;justify-content:space-between}.bit-demo input{width:100%;accent-color:#0865cf;margin:10px 0}.bit-demo svg{width:100%;fill:#263a50}.bit-readout{display:flex;justify-content:space-between;font-size:13px}.bit-demo p{font-size:12px;color:#536274;margin-bottom:0}
@media(max-width:760px){.reader.glossary-reader{left:8px;right:8px;width:auto}.site-header nav{gap:4px}.site-header nav button{font-size:11px;padding:7px}.glossary-list button{padding-left:0}.reader.glossary-reader .reader-body{padding:16px}.bit-readout{gap:10px}}

.formula-group{margin:0 0 26px}.formula-group>h3{font-size:18px;margin:0 0 10px}.formula-calculation{border-top:1px solid #c8d2dc}.formula-calculation:last-child{border-bottom:1px solid #c8d2dc}.formula-calculation>summary{padding:15px 4px;cursor:pointer;font-weight:650;color:#193a59;line-height:1.6}.formula-calculation>summary:focus-visible{outline:2px solid #0865cf;outline-offset:2px}.formula-calculation[open]>summary{color:#065bbd}.formula-calculation-body{padding:0 4px 18px;min-width:0;overflow-wrap:anywhere}.formula-calculation-body>p{font-size:15px;line-height:1.8}.formula-calculation-body .symbol-definitions{font-size:14px}.formula-calculation-body h4{font-size:15px;margin:22px 0 10px}.formula-calculation-body [data-term-calculation]{font-size:14px;line-height:1.8}.formula-calculation-body .reading-equation{max-width:100%;box-sizing:border-box}@media(max-width:600px){.formula-calculation-body .symbol-definitions{grid-template-columns:minmax(40px,auto) minmax(0,1fr);gap:8px}.formula-calculation-body .reading-equation math{font-size:17px}}

/* Coupled optical settings expose the editable input and the dependent result. */
.aperture-heading{display:block;font-size:10px;letter-spacing:.08em;font-weight:750;margin-bottom:9px;color:#3b4d60}.aperture-choice{display:grid;grid-template-columns:1fr 1fr;gap:7px}.aperture-choice button{text-align:left;padding:10px;font-size:13px}.aperture-choice button span{display:block;font-weight:400;font-size:10px;margin-top:4px;line-height:1.4}.aperture-result{display:flex;align-items:center;justify-content:space-between;gap:12px;margin:13px 0 8px;padding:12px 0;border-top:1px solid #b7c2ce;border-bottom:1px solid #b7c2ce}.aperture-result>div>span{font-size:10px;letter-spacing:.04em;display:block}.aperture-result strong{font-size:24px;color:#103d65;display:block;margin-top:4px;font-variant-numeric:tabular-nums}.aperture-result .aperture-equation{display:flex;flex-direction:column;margin:0;font-size:13px;gap:5px}.aperture-equation span{font-size:12px!important;letter-spacing:0!important}.control-hint{display:block;font-size:10px;line-height:1.6;color:#5b6470;margin-top:7px}.spot-scale{display:flex;align-items:center;flex-wrap:wrap;gap:8px;padding:12px 0}.spot-scale strong{width:100%;font-size:11px;letter-spacing:.06em;margin-bottom:5px}.spot-scale label{display:flex;align-items:center;gap:8px;font-size:11px}.spot-scale select{font-size:12px;background:white;border:1px solid #acb6c2;padding:5px}.spot-scale button{font-size:11px;padding:5px 8px}.spot-comparison{display:grid;grid-template-columns:1fr 1fr;gap:10px}.spot-comparison svg{min-width:0;width:100%;overflow:hidden}.spot-scale-caption{font-size:11px!important}.ray-focus-note{font-size:12px;line-height:1.6;color:#455b6e;padding:0 20px;margin:0 0 13px}@media(max-width:600px){.aperture-result{align-items:flex-start;flex-wrap:wrap}.aperture-result .aperture-equation{font-size:12px}.spot-comparison{grid-template-columns:1fr}.spot-comparison svg{max-width:320px;margin:auto}.ray-focus-note{padding:0 12px}.aperture-choice button{font-size:12px;padding:8px}}