/* Question-solving UX — release 2026.09.17.14 */
:root{--q-surface:color-mix(in srgb,var(--paper) 96%,var(--soft));--q-quiet:color-mix(in srgb,var(--soft) 34%,var(--paper));--q-shadow:0 12px 32px rgba(15,34,58,.07)}
.right{scrollbar-gutter:stable}.qhead{background:color-mix(in srgb,var(--paper) 96%,transparent);backdrop-filter:blur(12px)}
.qmeta{margin:10px 0 5px}.qmetaLine{font-weight:750}.objectiveLine{line-height:1.42;max-width:62ch}.questionState{margin:5px 0 9px}
.qUtilityDetails{margin:6px 0 10px}.qUtilityDetails>summary{list-style:none;cursor:pointer;display:inline-flex;align-items:center;gap:6px;color:var(--muted);font-size:10px;font-weight:850;letter-spacing:.04em;text-transform:uppercase;border:1px solid var(--line);border-radius:999px;padding:6px 9px;background:var(--paper)}.qUtilityDetails>summary::-webkit-details-marker{display:none}.qUtilityDetails>summary:after{content:'＋';font-size:11px}.qUtilityDetails[open]>summary:after{content:'−'}.qUtilityDetails .qcontrols{margin:8px 0 0;padding:9px;border:1px solid var(--line);border-radius:12px;background:var(--q-quiet)}
.qtools{margin:6px 0 12px}.confidence{padding:4px;border:1px solid var(--line);border-radius:10px;background:var(--q-quiet)}.confidenceLabel{padding-left:4px}.flagBtn{min-height:36px}
.qstem{font-size:15.5px;line-height:1.58;font-weight:720;border-radius:15px;padding:16px 16px;margin:8px 0 13px;background:var(--q-surface);box-shadow:var(--q-shadow);border-left:4px solid color-mix(in srgb,var(--blue) 72%,var(--line))}
#choices{display:grid;gap:8px}.choice{margin:0;min-height:52px;border-radius:13px;padding:12px 13px;line-height:1.47;font-size:13.5px;background:var(--paper);box-shadow:0 3px 12px rgba(15,34,58,.025);align-items:flex-start}.choice:hover{transform:none;box-shadow:0 7px 18px rgba(15,34,58,.07);border-color:color-mix(in srgb,var(--blue) 62%,var(--line))}.choice.sel{background:color-mix(in srgb,var(--soft) 62%,var(--paper));box-shadow:0 0 0 2px color-mix(in srgb,var(--blue) 24%,transparent)}.choice .letter{display:grid;place-items:center;flex:0 0 26px;width:26px;height:26px;border-radius:8px;background:var(--q-quiet);font-size:11px;margin-top:-1px}.choice.sel .letter{background:var(--blue);color:#fff}.choice.correct .letter{background:var(--green);color:#fff}.choice.wrong .letter{background:var(--red);color:#fff}
.nextrow{position:sticky;bottom:0;z-index:3;margin:14px -2px 0;padding:10px 2px calc(8px + env(safe-area-inset-bottom));background:linear-gradient(180deg,transparent 0,var(--paper) 22%,var(--paper) 100%)}.nextrow button{min-height:44px;font-weight:750}.nextrow #checkBtn{flex:1.35}.nextrow #checkBtn:disabled{opacity:.58}
.answerbox{border:0!important;background:transparent!important;padding:0!important;margin-top:16px!important}.answerbox.show{display:grid!important;gap:10px}.answerbox>.result{margin:0;border-radius:14px;padding:12px 14px;font-size:14px;display:flex;align-items:center;gap:8px}.answerbox>.result.good{background:color-mix(in srgb,var(--green) 11%,var(--paper));border:1px solid color-mix(in srgb,var(--green) 35%,var(--line))}.answerbox>.result.bad{background:color-mix(in srgb,var(--red) 10%,var(--paper));border:1px solid color-mix(in srgb,var(--red) 35%,var(--line))}.answerbox>.result.good:before{content:'✓';font-size:16px}.answerbox>.result.bad:before{content:'×';font-size:18px}
#why{border:1px solid var(--line);border-radius:15px;padding:14px;background:var(--q-surface);box-shadow:var(--q-shadow)}.answerLabel{font-size:9px;letter-spacing:.12em;margin:11px 0 4px}.answerLabel:first-child{margin-top:0}.correctAnswerLine{padding:9px 10px;border-radius:10px;background:color-mix(in srgb,var(--green) 8%,var(--paper));border-left:3px solid var(--green);line-height:1.42}.answerbox p{font-size:12.5px;line-height:1.58;margin:5px 0 0}.selectedWhy{border-radius:12px;padding:11px 12px;line-height:1.52}.trapBox{border-radius:12px;padding:11px 12px;line-height:1.5;background:color-mix(in srgb,var(--orange) 10%,var(--paper))}.pearl{margin:0!important;border:1px solid color-mix(in srgb,var(--blue) 30%,var(--line));border-left:4px solid var(--blue);border-radius:14px!important;padding:12px 13px!important;background:color-mix(in srgb,var(--soft) 55%,var(--paper))!important;font-size:12.5px!important;line-height:1.5}.pearl .answerLabel{color:var(--blue);margin:0 0 4px}.choiceReview{border-radius:12px;margin-top:11px}.choiceReview summary{padding:10px 11px}.choiceReviewItem{line-height:1.52}.repairActions{border-radius:14px;padding:12px;background:color-mix(in srgb,var(--yellow) 36%,var(--paper))}.repairActionsText{font-size:12px;line-height:1.48}.repairBtn{min-height:40px;padding:9px 11px}
.qAnswered .qtools{opacity:.68}.qAnswered .confidence{display:none}.qAnswered .objectiveLine{opacity:.75}.qAnswered .nextrow #nextBtn{background:var(--blue);border-color:var(--blue);color:#fff}.qAnswered .nextrow #checkBtn{display:none}
.qindex{max-height:98px;overflow:auto;align-content:flex-start;padding-right:3px}.masteryLegend,.keyboard{opacity:.78}.copyright{opacity:.72}
/* Exam mode: remove tutor cues and visual noise */
.examActive .qUtilityDetails,.examActive .masteryLegend,.examActive .keyboard,.examActive .objectiveLine{display:none!important}.examActive .qhead{border-bottom-color:color-mix(in srgb,var(--blue) 35%,var(--line))}.examActive .qstem{border-left-color:var(--ink);box-shadow:none;background:var(--paper)}.examActive .choice{box-shadow:none}.examActive .nextrow{background:linear-gradient(180deg,transparent 0,var(--paper) 25%,var(--paper) 100%)}.examActive .qtools{justify-content:flex-start}.examActive .flagBtn{font-weight:800}.examActive .qindex{max-height:74px}.examBanner{position:sticky;top:58px;z-index:3;box-shadow:0 7px 22px rgba(15,34,58,.08)}
.examReviewItem{padding:13px;border-radius:14px}.examReviewItem .stem{font-size:13.5px;line-height:1.5}.examReviewItem .answers{line-height:1.55}.examReviewItem details p{line-height:1.55}.examScoreCircle strong{font-size:27px}
@media(max-width:980px){.qstem{font-size:15px}.choice{font-size:14px;min-height:54px;padding:13px}.qindex{max-height:80px}.examBanner{top:0}}
@media(max-width:620px){.right{padding:13px 13px 18px}.qhead{margin:-2px -2px 8px;padding:2px 2px 9px}.qstem{font-size:15px;line-height:1.56;padding:14px 13px;margin-top:7px}.choice{font-size:14px;line-height:1.48;padding:13px 12px;gap:9px}.choice .letter{flex-basis:28px;width:28px;height:28px}.qtools{align-items:flex-start}.confidence{width:100%;justify-content:space-between}.confidence button{flex:1;min-height:35px}.nextrow{gap:6px;margin-top:12px}.nextrow button{padding:9px 7px}.answerbox p{font-size:13px}.repairBtn{flex:1}.qindex{display:grid;grid-template-columns:repeat(8,1fr);gap:5px;max-height:76px}.dot{width:100%;height:30px}.examBannerActions{width:100%;display:grid;grid-template-columns:1fr 1fr}.examTimer{grid-column:1/-1;text-align:left}.examSubmit{grid-column:1/-1}}
@media(prefers-reduced-motion:reduce){.choice,.answerbox{transition:none!important}.choice:hover{box-shadow:none}}