.task-banner { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 12px; padding: 18px 22px; border-radius: 14px; background: #e9def3; }
.task-banner h2 { margin: 0; font-size: 1.25rem; }
#score { color: var(--purple); font-weight: 700; }
.distance-figure { margin: 20px 0 28px; border: 1px solid var(--line); border-radius: 16px; background: white; overflow: hidden; }
.plot-scroll { overflow-x: auto; }
#distance-plot { display: block; width: 100%; min-width: 690px; }
#distance-plot text { fill: #383442; font: 17px Arial,sans-serif; }
#distance-plot .axis-title { font-size: 21px; font-weight: 700; }
.grid-minor { stroke: #ede9f0; stroke-width: 1; }
.grid-major { stroke: #d4cbdc; stroke-width: 1.3; }
.axis { fill: none; stroke: #383442; stroke-width: 2; }
#distance-curve { fill: none; stroke: #684890; stroke-width: 3; }
.measurement { fill: #383442; stroke: white; stroke-width: 1.5; }
.interval-fill { fill: #eac997; opacity: .18; }
.time-marker { stroke: #a45113; stroke-width: 2; stroke-dasharray: 8 5; }
#distance-plot .marker-label { fill: #8a400e; font-weight: 700; }
.distance-figure figcaption { padding: 15px 20px; display: flex; flex-wrap: wrap; gap: 12px 22px; font-size: .9rem; color: var(--muted); }
.distance-figure figcaption p { flex-basis: 100%; margin: 0; line-height: 1.5; }
.curve-key { color: var(--purple); font-weight: 700; }
.answer-card { padding: 24px; background: white; border: 1px solid var(--line); border-radius: 16px; }
.answer-card p { line-height: 1.5; }
.answer-grid { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 18px; margin: 20px 0; }
.answer-grid label { display: flex; flex-direction: column; gap: 10px; font-weight: 700; }
.input-unit { display: flex; align-items: center; gap: 9px; }
.input-unit input { width: 100%; min-width: 0; padding: 12px; border: 1px solid #a59aac; border-radius: 8px; font: inherit; }
input[aria-invalid="true"] { border: 2px solid #a83b25; }
.answer-card button { padding: 12px 18px; border: 0; border-radius: 10px; background: var(--purple); color: white; font: inherit; font-weight: 700; cursor: pointer; }
.answer-card button:disabled { opacity: .55; cursor: default; }
button:focus-visible, input:focus-visible, .plot-scroll:focus-visible { outline: 3px solid #d38857; outline-offset: 3px; }
#feedback { margin: 16px 0 0; min-height: 3em; }
#feedback.success { color: #236341; font-weight: 700; }
@media(max-width:600px) { .answer-grid { grid-template-columns: 1fr; } .answer-card { padding: 18px; } }

.solved-card { margin-top: 28px; padding: 24px; border: 1px solid var(--line); border-radius: 16px; background: #f0e9f6; }
.solved-card h2 { font-size: 1.4rem; }
#solved-empty { color: var(--muted); line-height: 1.5; }
#solved-list { margin: 0; padding-left: 26px; }
#solved-list li { padding: 14px 0; border-bottom: 1px solid #d8cce3; }
#solved-list li:last-child { border-bottom: 0; padding-bottom: 0; }
#solved-list li::marker { color: var(--purple); font-weight: 700; }
#solved-list p { margin: 0; line-height: 1.7; overflow-wrap: anywhere; font-variant-numeric: tabular-nums; }
#solved-list p:first-child { font-weight: 700; }

[hidden] { display: none !important; }
.history-info { font-size: .88rem; color: var(--muted); line-height: 1.6; }
.solved-card button { padding: 12px 16px; border: 0; border-radius: 10px; background: var(--purple); color: white; font: inherit; cursor: pointer; }
.solved-card button:disabled { opacity: .5; cursor: default; }
#qr-result { margin-top: 24px; padding-top: 20px; border-top: 1px solid var(--line); }
#history-qr { display: block; width: min(100%,440px); height: auto; background: white; shape-rendering: crispEdges; margin: 18px auto; }
#qr-payload { display: block; overflow-wrap: anywhere; padding: 12px 0; }
#qr-result details { margin-bottom: 20px; }