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@media(max-width:600px){.scene-legend{padding:10px 18px 0;gap:12px;justify-content:center;font-size:10px}}
/* Readable stacked energy diagram on narrow screens. */
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/* Revision 2: original dark ETTcogen palette; benefits visible in the diagram. */
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@keyframes benefit-appear{from{opacity:.45;transform:translateY(4px)}to{opacity:1;transform:none}}
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