/* Whole areas are independent choices; details remain a separate disclosure. */
.problem-area-select{display:grid;grid-template-columns:65px minmax(0,1fr) 20px;gap:12px;align-items:center;padding:17px 13px;cursor:pointer;min-width:0}
.problem-area-select input{appearance:auto;accent-color:#557b58;width:20px;height:20px;margin:0;cursor:pointer}
.problem-area-select .problem-area-meta{font-weight:600;color:#ead09a}
.problem-area-select:hover .problem-area-art{transform:translateY(-3px)}
.problem-area.whole-area-selected{background:linear-gradient(135deg,#546046aa,#283d2eaa);border-color:#c8d6a0}
.problem-area.whole-area-selected .problem-area-meta{color:#dceabb}
.problem-area-details>summary{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:11px 16px;min-height:46px;border-top:1px solid #c3a16644;color:#e0cca9;font:400 12px/1.5 var(--sans)}
.problem-area-details>summary b{font-weight:400}
.problem-area-details>summary .problem-expand{align-self:center;margin:0;font-size:21px}
.problem-area-details[open]>summary .problem-expand::before{content:'−'}
.problem-area-details .problem-area-body{padding-top:3px}
.problem-area-select:focus-within{outline:3px solid #f4d17d;outline-offset:-4px;border-radius:12px}

/* This small sticky basket belongs only to the problem selector. */
.problem-selection-anchor{position:sticky;top:18px;z-index:35;min-height:72px;display:flex;justify-content:flex-end;align-items:flex-start;margin-bottom:16px;pointer-events:none}
.problem-selection-anchor[hidden],.problem-selection[hidden]{display:none!important}
.problem-selection-anchor .problem-selection{position:relative;width:250px;max-width:100%;margin:0;padding:0;pointer-events:auto;border-radius:12px;background:linear-gradient(145deg,#57422e,#34271f);box-shadow:0 5px 18px #120b0880}
.problem-selection .problem-basket-toggle{display:grid;grid-template-columns:21px minmax(0,1fr) auto 12px;align-items:center;gap:9px;width:100%;min-height:70px;padding:10px 13px;border:0;border-radius:12px;background:transparent;color:var(--gold);text-align:left}
.problem-basket-toggle svg{display:block;width:21px;height:21px}
.problem-basket-label{display:block;min-width:0}
.problem-basket-label strong{display:block;font:400 21px/1.3 var(--serif)}
.problem-basket-preview{display:block;margin-top:3px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;color:#e1cdaa;font:400 11px/1.5 var(--sans)}
.problem-basket-toggle .problem-selection-total{min-width:27px;height:27px;font-size:12px}
.problem-basket-chevron{display:block;width:8px;height:8px;border-right:1.5px solid currentColor;border-bottom:1.5px solid currentColor;transform:translateY(-2px) rotate(45deg)}
.problem-basket-toggle[aria-expanded=true] .problem-basket-chevron{transform:translateY(2px) rotate(225deg)}
.problem-selection .problem-selection-panel{position:absolute;top:calc(100% + 7px);right:0;width:296px;max-width:calc(100vw - 32px);max-height:min(440px,55svh,var(--selection-panel-height,440px));overflow:auto;overscroll-behavior:contain;margin:0;padding:10px 13px 13px;border:1px solid #cba45d;border-radius:12px;background:linear-gradient(145deg,#57422e,#34271f);box-shadow:0 8px 22px #120b0880}
.problem-selection.opens-up .problem-selection-panel{top:auto;bottom:calc(100% + 7px)}
.problem-selection .problem-selection-list{display:grid;grid-template-columns:1fr;gap:0}
.problem-selection .problem-selection-list li{grid-template-columns:30px minmax(0,1fr) 40px;gap:7px;padding:5px 0}
.problem-selection .problem-selection-list span{font-size:13px;line-height:1.55}
.problem-selection .problem-selection-list button{width:40px;height:44px}
.problem-selection .problem-selection-actions{display:grid;grid-template-columns:1fr;gap:8px;padding-top:12px}
.problem-selection .problem-selection-copy,.problem-selection .problem-selection-link{min-height:44px;font-size:12px;padding:9px 10px}
.problem-selection .problem-selection-clear{grid-column:auto;min-height:40px;padding:5px;font-size:12px}
.problem-selection .problem-selection-note{margin-top:9px;padding-top:9px;font-size:11px;line-height:1.6}
.problem-selection .problem-copy-fallback textarea{min-height:100px}
@media(min-width:900px){
 .problem-area-select{grid-template-columns:80px minmax(0,1fr) 22px;gap:15px;padding:20px 18px 16px}
 .problem-area-select input{width:22px;height:22px}
 .problem-area-details>summary{padding:12px 18px;font-size:13px}
}
@media(max-width:699px){
 .problem-selection-anchor{top:12px;min-height:64px;margin-bottom:13px}
 .problem-selection-anchor .problem-selection{width:216px}
 .problem-selection .problem-basket-toggle{min-height:62px;padding:9px 11px;gap:7px}
 .problem-basket-label strong{font-size:20px}
 .problem-basket-preview{font-size:10px}
 .problem-area-select{padding:15px 13px}
 .problem-selection .problem-selection-panel{max-height:min(48svh,var(--selection-panel-height,440px))}
}
@media(prefers-reduced-motion:reduce){.problem-area-select:hover .problem-area-art{transform:none}}

/* Both columns use whole-area cards and individually selectable illustrated examples. */
.problem-theory-list{display:block}
.problem-theory-area .problem-area-name{font-size:clamp(22px,2.1vw,27px);line-height:1.3;text-wrap:pretty}
.problem-example-choices{display:grid;gap:9px;margin:5px 0 13px;padding-top:11px;border-top:1px solid #b3966055}
.problem-area-details>.problem-area-body>.problem-example-choices{margin:6px 0 0;padding-top:0;border-top:0}
.problem-example-choice{display:grid;grid-template-columns:44px minmax(0,1fr) 20px;gap:10px;align-items:center;min-width:0;min-height:72px;padding:11px 10px;border:1px solid #c5a973;border-radius:10px;background:#fff9ed;cursor:pointer;color:#4d3c29}
.problem-example-choice>img{display:block;width:44px;height:53px;object-fit:contain}
.problem-example-choice>span{min-width:0;font:400 13px/1.65 var(--sans);text-wrap:pretty}
.problem-example-choice input{appearance:auto;accent-color:#44674e;width:20px;height:20px;margin:0;cursor:pointer}
.problem-example-choice:hover{border-color:#7f9467}
.problem-example-choice:has(input:checked){border-color:#537650;background:#e5efda;box-shadow:inset 0 0 0 1px #537650}
.problem-example-choice:focus-within{outline:3px solid #537650;outline-offset:2px}
@media(min-width:900px){.problem-example-choice{grid-template-columns:50px minmax(0,1fr) 20px;gap:12px;padding:14px 12px}.problem-example-choice>img{width:50px;height:60px}.problem-example-choice>span{font-size:14px}}
@media(max-width:400px){.problem-example-choice{grid-template-columns:36px minmax(0,1fr) 20px;gap:8px;padding:10px 8px}.problem-example-choice>img{width:36px;height:46px}}