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@media(max-width:760px){.chem-element-filters{grid-template-columns:minmax(0,1fr)}.chem-element-filters>button{justify-self:start}.chem-element-results{max-height:150px}.chem-periodic{min-width:900px}.chem-element-filters .chem-search label{font-size:.75rem}}
@media(max-width:760px){.chem-course>summary{padding:18px 16px;gap:10px;font-size:.75rem}.chem-course>summary strong{font-size:.65rem}.chem-course>summary>span::before{margin-right:6px}.chem-course-body{grid-template-columns:minmax(0,1fr);gap:22px;padding:2px 16px 22px}.chem-challenge-card{padding:16px}.chem-course-body h2{font-size:1.3rem}.chem-challenge-card>.chem-actions button{flex:1 1 45%}.chem-challenge-list{margin-top:16px}}

@media(prefers-reduced-motion:reduce){.chem-main *{animation:none!important;transition:none!important;scroll-behavior:auto!important}}
/* Onglets : 5 ateliers sur grand écran ; le 5e occupe toute la ligne sur mobile (grille de 2). */
.chem-tabs{grid-template-columns:repeat(5,minmax(0,1fr))}
@media(max-width:760px){.chem-tabs{grid-template-columns:repeat(2,minmax(0,1fr))}.chem-tabs button:last-child{grid-column:1/-1}}
/* Atelier « Calculer » */
.chem-calc-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px;margin-top:20px}
.chem-calc-card{display:grid;gap:10px;align-content:start}
.chem-calc-card h3{margin:6px 0 0;font-size:1.05rem}
.chem-calc-card label{font-size:.78rem;color:var(--chem-muted)}
.chem-calc-card .chem-caption{margin:0}
.chem-calc-examples{display:flex;flex-wrap:wrap;gap:6px}
.chem-main .chem-calc-examples button{min-height:34px;padding:6px 10px;font-size:.74rem;border-radius:999px}
.chem-calc-result{display:flex;align-items:baseline;gap:8px;margin:6px 0 0;font-size:.85rem;color:var(--chem-muted)}
.chem-calc-result strong{font-size:1.6rem;color:var(--chem-green);font-variant-numeric:tabular-nums}
.chem-calc-equation strong{font-size:1.25rem;line-height:1.4;color:var(--chem-text)}
.chem-calc-convert{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}
.chem-calc-convert label{display:grid;gap:6px}
.chem-calc-card .chem-feedback{margin-top:4px}
@media(max-width:1050px){.chem-calc-grid{grid-template-columns:minmax(0,1fr)}}
@media(max-width:560px){.chem-calc-convert{grid-template-columns:minmax(0,1fr)}}