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@media(max-width:1200px){.ed-inputs{grid-template-columns:repeat(3,minmax(0,1fr))}.ed-control:nth-child(3n+1){border-left:0}.ed-control:nth-child(n+4){border-top:1px solid var(--line)}.ed-control:last-child{grid-column:auto}.hardware-controls{grid-template-columns:repeat(3,1fr)}.header-tag{display:none}.site-header nav{margin-left:auto}.ed-number input{font-size:25px}}
@media(max-width:980px){.ed-results>.ed-result-note{display:block}.ed-result-note>p{margin-top:12px!important}.ed-result-note>a{display:inline-block;margin-top:12px}.class-strip>div{padding:17px 15px}.class-strip strong{font-size:23px}.hardware-heading{display:block}.hardware-heading p{margin-top:14px;max-width:none}.reference-frame{height:230px}.cathode-reference{grid-template-columns:100px 100px 1fr;padding:16px;gap:14px}.cathode-reference img{width:100px;height:145px}.collector-heading{display:block}.collector-heading p{max-width:none;margin-top:14px}.collector-buttons button:last-child{margin-left:0}.ed-results strong{font-size:28px}}
@media(max-width:700px){.brand>span{font-size:20px}.class-strip{grid-template-columns:repeat(3,1fr);margin-bottom:24px}.class-strip>div{padding:15px 11px}.class-strip span{font-size:6px;letter-spacing:.3px}.class-strip strong{font-size:22px}.class-strip>div:nth-child(4){border-left:0}.class-strip>div:nth-child(n+4){border-top:1px solid var(--line)}.class-strip small{font-size:10px}.hardware-section{margin-bottom:30px}.hardware-heading h2{font-size:22px}.hardware-heading p{font-size:10px}.reference-tabs button{flex:1 1 31%;padding:11px 7px;font-size:9px;line-height:1.5}.reference-frame{height:155px}.reference-frame[data-kind=portrait]{height:350px}.reference-caption{display:block;padding:15px}.reference-caption p{margin-top:10px;font-size:10px}.reference-caption strong{font-size:12px}.hardware-controls{grid-template-columns:repeat(2,1fr)}.hardware-controls button{font-size:10px;padding:11px 7px}.hardware-detail{padding:16px}.hardware-detail p{font-size:10px}.ed-inputs{grid-template-columns:1fr 1fr}.ed-control:nth-child(odd){border-left:0}.ed-control:nth-child(even){border-left:1px solid var(--line)}.ed-control:nth-child(n+3){border-top:1px solid var(--line)}.ed-control:last-child{grid-column:auto}.ed-control:last-child>label{min-height:32px}.ed-results{grid-template-columns:1fr 1fr}.ed-results>div:nth-child(3){grid-column:1/-1;border-left:0;border-top:1px solid var(--line)}.ed-results>.ed-result-note{grid-column:1/-1}.ed-results strong{font-size:28px}.ed-power-help{padding:14px 17px;font-size:9px}.cathode-reference{grid-template-columns:1fr 1fr;gap:14px}.cathode-reference img{width:100%;height:160px;object-fit:contain}.cathode-reference>div{grid-column:1/-1}.cathode-reference h3{font-size:17px}.cathode-reference p{font-size:10px}.optics-current-strip{padding:15px 14px;gap:10px 20px;font-size:9px}.collector-heading{padding:22px 18px 10px}.collector-heading h3{font-size:23px}.collector-heading p{font-size:10px}.collector-buttons{padding:8px 18px;gap:8px}.collector-buttons button{font-size:9px;padding:9px 10px}.collector-scroll #collector-canvas{min-width:660px}.collector-notes{grid-template-columns:1fr;padding:16px 18px;gap:10px}.collector-lab>.fine-print{padding:0 18px 18px}.collector-notes p{font-size:10px}}

@media(min-width:701px) and (max-width:980px){.site-header{height:auto;flex-wrap:wrap;gap:15px;padding-top:20px;padding-bottom:0}.site-header .brand>span{font-size:20px;letter-spacing:2px}.site-header nav{margin-left:0;flex-basis:100%;display:grid;grid-template-columns:1fr 1.4fr;border-top:1px solid var(--line);gap:0}.site-header nav a{display:flex;align-items:center;justify-content:center;padding:13px 10px;font-size:12px;line-height:1.6}.site-header nav a:first-child{border-right:1px solid var(--line)}.site-header nav .nav-current{box-shadow:inset 0 -2px var(--amber);color:var(--amber)}.hero{display:block;padding-block:35px}.hero-aside{width:auto;margin-top:23px}.hero-aside p{font-size:13px}.hero h1{font-size:43px}html{scroll-padding-top:155px}}

.reference-frame[data-kind=tube]{height:auto;aspect-ratio:3.8}.reference-frame[data-kind=tube] img{object-fit:cover}@media(max-width:700px){.reference-frame[data-kind=tube]{height:110px;aspect-ratio:auto}}

.class-strip span{min-height:28px;letter-spacing:.3px;line-height:1.6}.hero h1{font-size:clamp(32px,4vw,64px);letter-spacing:-1.5px}.gun-controls-link{display:flex;justify-content:space-between;gap:16px;padding:13px 24px;border-top:1px solid var(--line);font-size:10px;line-height:1.8;color:#8ea5b8}.gun-controls-link a{color:#c4a2da}.anode-label{fill:#c4a2da!important}#ed-anode-node{cursor:pointer}#optics-gun-controls{scroll-margin-top:150px}@media(max-width:700px){.gun-controls-link{display:block;padding:13px}.gun-controls-link a{display:block;margin-top:8px}.class-strip span{min-height:34px;font-size:7px}.hero h1{font-size:34px}.site-header nav a{font-size:10px}}

/* Brighter laboratory palette: legible surfaces, luminous copper and cyan. */
:root{--bg:#0c1728;--panel:#13243a;--line:#35516b;--muted:#adc3d7;--text:#f2f8ff;--amber:#ffca78;--cyan:#70f1f2;--blue:#a4d7ff}
body{background:radial-gradient(ellipse at 80% 0,#17334a66,transparent 48%),var(--bg)}
.model-layout,.optics-layout,.ed-workspace,.ed-parameters,.ed-results,.learning-grid>*,.principles article,.thermal-layout,.collector-lab{background:#112238}
.stage-sidebar,.optics-settings{background:#152b43}.class-strip,.reference-tabs,.reference-caption,.cathode-reference,.hardware-detail{background:#14283e}
.brand-sub,.eyebrow,.model-note,.section-line{color:#b2cada}.hero h1{color:#fff3dc}.hero-aside p,.hardware-heading p,.hardware-detail p,.reference-caption p,.cathode-reference p,.collector-heading p,.optics-intro>p,.optics-settings-note,.optics-control>small,.fine-print,.phase-caption,.stage-short{color:#b1c6d8}
.class-strip strong,.ed-results strong{color:#ffcf89}.class-strip span{color:#b9ccdf}.class-strip small{color:#a8d8ec}
.apparatus{background:radial-gradient(ellipse at 45% 48%,#21517499,transparent 75%)}
.device-part{opacity:.8}.device-part.reached{opacity:.9}.device-part.focused{opacity:1;filter:drop-shadow(0 0 9px #ffc36e38)}
#device .diagram-label{fill:#c3d3e3}#device .diagram-small{fill:#a5bbce}#device .cyan-label{fill:#8af7f5}#device .blue-label{fill:#b3dfff}
.stage-button.active{background:#24405a;border-color:#ffc56a}.stage-button .stage-name{color:#e2edf8}.stage-button.active .stage-name{color:#ffda9e}
.reference-tabs button,.hardware-controls button,.collector-buttons button{color:#bfd5e5}.reference-tabs button.selected,.hardware-controls button.selected,.collector-buttons button.selected{background:#6a4f2a44;color:#ffda97;border-color:#ae864e}
input[type=range]{filter:brightness(1.18)}.optics-control output{color:#ffcf8b}.optics-status{color:#a0fff1;background:#1b615336}
.visual-response{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px 20px;border-top:1px solid var(--line);padding:17px 24px;background:linear-gradient(120deg,#173e56,#173048);font:10px var(--mono);color:#c4e9ff}
.visual-response span:nth-child(2){color:#88f6ef}.visual-response span:nth-child(3){color:#ffcf88}.visual-response small{grid-column:1/-1;font:10px/1.8 var(--font);color:#b3cee0}
.optics-motion{margin:0;padding:14px 22px;border-top:1px solid var(--line);font:10px/1.8 var(--mono);color:#b4eff6;background:#17384d}
.gun-controls-link{color:#bdd3e4}.gun-controls-link a{color:#dfc0ff}
@media(max-width:700px){.visual-response{padding:14px;gap:10px;font-size:9px}.visual-response small,.optics-motion{font-size:9px}.optics-motion{padding:13px 14px}.brand-sub{letter-spacing:1.1px!important}}

.ed-inputs{grid-template-columns:repeat(4,minmax(0,1fr))}.ed-control:nth-child(n){border-top:0;border-left:1px solid var(--line)}.ed-control:nth-child(4n+1){border-left:0}.ed-control:nth-child(n+5){border-top:1px solid var(--line)}
.ed-derived{background:linear-gradient(130deg,#264b5b77,#27344866)}.ed-number output{font:31px var(--mono);color:#92f5e7}.derived-tag{display:inline-block;color:#95efe2;font:8px var(--mono);letter-spacing:1px;padding:7px 0}.ed-derived>small{display:block;color:#b4d0dc;font-size:10px;line-height:1.7}.ed-control:last-child{grid-column:auto}.ed-control label{min-height:30px}
.coupling-strip{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:15px;padding:18px 24px;border-block:1px solid var(--line);background:#193c4b;color:#c7e2ef;font:10px/1.8 var(--mono)}.coupling-strip b{display:block;color:#ffce8c;font-size:16px;font-weight:400}.coupling-strip small{grid-column:1/-1;color:#aacbda;font:10px/1.8 var(--font)}#ed-gun-status{color:#99f4dd;align-self:center}#ed-gun-status.reflected{color:#ffb09a}.reference-tabs button{flex:1;padding-inline:12px}
@media(max-width:980px){.ed-inputs{grid-template-columns:repeat(2,minmax(0,1fr))}.ed-control:nth-child(n){border-left:1px solid var(--line);border-top:0}.ed-control:nth-child(odd){border-left:0}.ed-control:nth-child(n+3){border-top:1px solid var(--line)}.coupling-strip{grid-template-columns:1fr 1fr}.ed-number output{font-size:28px}.reference-tabs button{flex:1 1 24%}}
@media(max-width:700px){.ed-number output{font-size:26px}.ed-derived>small{font-size:9px}.coupling-strip{padding:15px;gap:12px;font-size:9px}.coupling-strip b{font-size:14px}.reference-tabs button{flex:1 1 31%}.ed-control label{font-size:10px;line-height:1.6}}

#ed-gun-controls{scroll-margin-top:130px}

.reference-pair{display:grid;gap:18px;margin:0 0 22px}.reference-pair figure{margin:0;border:1px solid var(--line);background:#14283e}.reference-pair-frame{aspect-ratio:4/1;overflow:hidden;background:white}.reference-pair-frame img{display:block;width:100%;height:100%;object-fit:cover;object-position:50% 30%}.reference-pair figure:nth-child(2) img{object-position:50% 50%}.reference-pair figcaption{padding:14px 20px;color:#c8dcea;font-size:12px;line-height:1.7}.reference-pair figcaption span{font:10px var(--mono);color:#ffcd87;margin-right:12px}
#device [data-part="0"]{opacity:1;filter:none}.visual-response #visual-radiation{grid-column:1/-1;color:#8af5ee}.legend{flex-wrap:wrap}.hotspots button[data-hotspot="0"]{background:#12273f}
@media(max-width:700px){.reference-pair{gap:12px}.reference-pair figcaption{font-size:10px;padding:11px 13px}.reference-pair-frame{aspect-ratio:3.5/1}.reference-pair-frame img{object-position:50% 25%}.reference-pair figure:nth-child(2) img{object-position:50% 50%}.apparatus{min-height:245px}.model-topbar .legend{gap:7px}}

.reference-pair{grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;align-items:center;margin-bottom:18px}.reference-pair figure{border:0;background:#142b48}.reference-pair-frame{aspect-ratio:4/1;background:#142b48;border:1px solid #34506d}.reference-pair-frame img{object-fit:contain;object-position:center!important}.reference-pair figcaption{display:none}.hardware-controls{grid-template-columns:repeat(5,minmax(0,1fr))}.hardware-controls button{font-size:10px;min-height:48px}.ed-control label{min-height:36px}.optics-settings .optics-control label>span{max-width:70%}
@media(max-width:980px){.hardware-controls{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media(max-width:700px){.reference-pair{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}.reference-pair-frame{aspect-ratio:3/1}.hardware-controls{grid-template-columns:repeat(2,minmax(0,1fr))}.hardware-controls button{font-size:9px}.ed-control label{font-size:10px;min-height:48px}.optics-settings .optics-control label>span{max-width:65%}}
.reference-pair-frame{aspect-ratio:3/1;max-height:180px}.reference-pair-frame img{object-fit:cover}.reference-pair{max-width:1120px;margin-inline:auto}