.practice-shell{max-width:52rem;margin:0 auto;padding:1.5rem 1rem 4rem}@media (width>=64rem){.practice-shell{padding:2.5rem 1.75rem 5rem}}.practice-shell>header h1{margin-top:.35rem;font-size:clamp(1.85rem,1.3rem + 2.2vw,2.6rem)}.practice-lede{max-width:62ch;color:var(--text-muted);margin-top:.75rem;font-size:1.05rem;line-height:1.65}.practice-shell>header{margin-bottom:1.75rem}.sr-only{clip-path:inset(50%);white-space:nowrap;width:1px;height:1px;position:absolute;overflow:hidden}.tool{border:1px solid var(--border);background:var(--bg-raised);border-radius:.5rem;padding:1.25rem}@media (width>=40rem){.tool{padding:1.6rem 1.75rem}}.tool+.tool,.dashboard>.tool+.tool{margin-top:1rem}.tool-quiet{background:var(--bg-subtle)}.tool-head{margin-bottom:1.25rem}.tool-title{margin-top:.3rem;font-size:1.4rem}.tool-lede{color:var(--text-muted);max-width:62ch;margin-top:.5rem;line-height:1.6}.tool-actions{flex-wrap:wrap;gap:.6rem;margin-top:1.25rem;display:flex}.tool-actions.center{justify-content:center}.tool-keys{color:var(--text-muted);margin-top:1.25rem;font-size:.8rem}.tool-keys code{font-family:var(--font-mono);font-size:.85em}kbd{font-family:var(--font-mono);border:1px solid var(--border-strong);background:var(--bg-subtle);border-bottom-width:2px;border-radius:.25rem;padding:.1rem .4rem;font-size:.75em}.tool-toolbar{flex-wrap:wrap;align-items:flex-end;gap:1rem 1.5rem;margin-bottom:1.25rem;display:flex}.btn-ok{border-color:var(--callout-tip);color:var(--callout-tip)}.btn-ok:hover{background:var(--callout-tip-bg);color:var(--callout-tip);border-color:var(--callout-tip)}.btn-bad{border-color:var(--callout-mistake);color:var(--callout-mistake)}.btn-bad:hover{background:var(--callout-mistake-bg);color:var(--callout-mistake);border-color:var(--callout-mistake)}.btn:disabled{opacity:.45;cursor:not-allowed}.btn{cursor:pointer;font-family:var(--font-sans)}.field{border:0;gap:.35rem;min-width:0;margin:0;padding:0;display:grid}.field.grow{flex:14rem}.field-label{font-family:var(--font-mono);letter-spacing:.1em;text-transform:uppercase;color:var(--text-muted);font-size:.7rem}.field input[type=text],.field select{font:inherit;font-family:var(--font-mono);border:1px solid var(--border-strong);background:var(--bg);color:var(--text);border-radius:.4rem;width:100%;min-width:0;padding:.6rem .8rem}.field select{font-family:var(--font-sans);max-width:100%}.field input.ok{border-color:var(--callout-tip)}.field input.bad{border-color:var(--callout-mistake)}.segmented{border:1px solid var(--border-strong);border-radius:.4rem;display:inline-flex;overflow:hidden}.segmented button{font:inherit;color:var(--text-muted);cursor:pointer;background:0 0;border:0;padding:.45rem .9rem;font-size:.9rem}.segmented button+button{border-left:1px solid var(--border-strong)}.segmented button.on{background:var(--accent);color:var(--accent-contrast)}.chip-row{flex-wrap:wrap;gap:.4rem;display:flex}.chip,.chip-toggle{border:1px solid var(--border-strong);color:var(--text-muted);background:var(--bg-subtle);border-radius:999px;align-items:center;gap:.35rem;padding:.3rem .7rem;font-size:.8rem;display:inline-flex}.chip-toggle{cursor:pointer;user-select:none}.chip-toggle input{opacity:0;width:1px;height:1px;position:absolute}.chip-toggle.on{border-color:var(--accent);color:var(--accent);background:var(--accent-soft)}.chip-toggle:has(input:focus-visible){outline:2px solid var(--focus);outline-offset:2px}.stat-row{color:var(--text-muted);flex-wrap:wrap;gap:.5rem 1.25rem;margin-bottom:1rem;font-size:.875rem;display:flex}.stat strong{color:var(--text);font-size:1.05rem}.stat.ok strong{color:var(--callout-tip)}.stat.bad strong{color:var(--callout-mistake)}.stat.mono,.mono{font-family:var(--font-mono)}.progress-bar{background:var(--border);border-radius:999px;height:4px;margin-top:.75rem;overflow:hidden}.progress-bar>span{background:var(--accent);height:100%;transition:width .25s;display:block}.quiz-meta{color:var(--text-muted);justify-content:space-between;gap:1rem;margin-top:.4rem;font-size:.875rem;display:flex}.quiz-stem{max-width:68ch;font-size:1.15rem;line-height:1.55}.quiz-stem code,.choice-text code,.feedback-body code,.flashcard-text code,.result-text code{font-family:var(--font-mono);background:var(--bg-subtle);border:1px solid var(--border);border-radius:.25rem;padding:.08em .3em;font-size:.88em}.quiz-hint{color:var(--text-muted);margin-top:.5rem;font-size:.85rem}.quiz-question .code-wrap{margin-top:1rem;margin-bottom:0}.choice-list{gap:.5rem;margin-top:1.25rem;display:grid}.choice{text-align:left;font:inherit;border:1px solid var(--border-strong);background:var(--bg);color:var(--text);cursor:pointer;border-radius:.4rem;align-items:flex-start;gap:.85rem;padding:.75rem .9rem;line-height:1.5;transition:border-color .12s,background .12s;display:flex}.choice:hover:not(:disabled){border-color:var(--accent)}.choice:disabled{cursor:default}.choice-letter{font-family:var(--font-mono);border:1px solid var(--border-strong);width:1.6rem;height:1.6rem;color:var(--text-muted);border-radius:.3rem;flex-shrink:0;justify-content:center;align-items:center;margin-top:.1rem;font-size:.8rem;display:inline-flex}.choice.selected{border-color:var(--accent);background:var(--accent-soft)}.choice.selected .choice-letter{border-color:var(--accent);color:var(--accent)}.choice.correct{border-color:var(--callout-tip);background:var(--callout-tip-bg)}.choice.correct .choice-letter{background:var(--callout-tip);border-color:var(--callout-tip);color:#fff}.choice.wrong{border-color:var(--callout-mistake);background:var(--callout-mistake-bg)}.choice.wrong .choice-letter{background:var(--callout-mistake);border-color:var(--callout-mistake);color:#fff}.choice.muted{opacity:.55}.feedback{border:1px solid;border-left-width:3px;border-radius:.4rem;margin-top:1.25rem;padding:1rem 1.15rem}.feedback.ok{border-color:color-mix(in oklab, var(--callout-tip) 35%, transparent);border-left-color:var(--callout-tip);background:var(--callout-tip-bg)}.feedback.bad{border-color:color-mix(in oklab, var(--callout-mistake) 35%, transparent);border-left-color:var(--callout-mistake);background:var(--callout-mistake-bg)}.feedback-title{font-weight:600}.feedback.ok .feedback-title{color:var(--callout-tip)}.feedback.bad .feedback-title{color:var(--callout-mistake)}.feedback-body{margin-top:.5rem;line-height:1.6}.feedback .tool-actions{margin-top:1rem}.result-list{gap:.5rem;margin-top:1.5rem;display:grid}.result-list li{border:1px solid var(--border);border-radius:.4rem;gap:.75rem;padding:.6rem .8rem;font-size:.925rem;line-height:1.5;display:flex}.result-list li.ok{border-left:3px solid var(--callout-tip)}.result-list li.bad{border-left:3px solid var(--callout-mistake)}.result-mark{font-family:var(--font-mono);flex-shrink:0}.result-list li.ok .result-mark{color:var(--callout-tip)}.result-list li.bad .result-mark{color:var(--callout-mistake)}.result-n{color:var(--text-muted);font-family:var(--font-mono);font-size:.85em}.result-answer{color:var(--text-muted);margin-top:.25rem;font-size:.85em;display:block}.flashcard{perspective:1200px;cursor:pointer;width:100%;min-height:15rem;font:inherit;color:inherit;text-align:center;background:0 0;border:0;border-radius:.6rem;padding:0;display:block}.flashcard-inner{width:100%;min-height:15rem;transform-style:preserve-3d;transition:transform .45s cubic-bezier(.4,.2,.2,1);display:block;position:relative}.flashcard.flipped .flashcard-inner{transform:rotateY(180deg)}.flashcard-face{border:1px solid var(--border-strong);background:var(--bg);backface-visibility:hidden;border-radius:.6rem;flex-direction:column;justify-content:center;align-items:center;gap:.9rem;padding:1.5rem;display:flex;position:absolute;inset:0}.flashcard-face.back{border-color:var(--accent);transform:rotateY(180deg)}.flashcard-text{font-family:var(--font-display);text-wrap:balance;max-width:34ch;font-size:clamp(1.15rem,1rem + 1vw,1.55rem);line-height:1.35}.flashcard-face.back .flashcard-text{font-family:var(--font-sans);font-size:clamp(1rem,.95rem + .5vw,1.2rem);line-height:1.5}.flashcard-foot{color:var(--text-muted);font-size:.75rem;font-family:var(--font-mono)}@media (prefers-reduced-motion:reduce){.flashcard-inner{transition:none;transform:none!important}.flashcard-face{backface-visibility:visible;position:relative;transform:none}.flashcard-face.back,.flashcard.flipped .flashcard-face.front{display:none}.flashcard.flipped .flashcard-face.back{display:flex}}.card-done{text-align:center;padding:2rem 0}.problem-card{margin-top:.5rem}.problem-prompt{max-width:68ch;margin-top:.35rem;font-size:1.15rem;line-height:1.55}.answer-form{flex-wrap:wrap;align-items:flex-end;gap:.75rem;margin-top:1.25rem;display:flex}.answer-form .btn{height:2.75rem}.problem-card .code-wrap{margin-top:1rem;margin-bottom:0}.problem-card .code-block{font-size:.8rem}.domain-rows{gap:.9rem;display:grid}.domain-row-head{justify-content:space-between;gap:1rem;font-size:.95rem;display:flex}.domain-row-head a{color:var(--text);text-decoration:none}.domain-row-head a:hover{color:var(--accent)}.domain-row-num{font-family:var(--font-mono);color:var(--text-muted);white-space:nowrap;font-size:.8rem}.domain-row .progress-bar{margin-top:.4rem}.weak-list{gap:.6rem;display:grid}.weak-list li{align-items:baseline;gap:.9rem;line-height:1.5;display:flex}.weak-score{font-family:var(--font-mono);color:var(--callout-mistake);min-width:3ch;font-size:.85rem}.box-row{grid-template-columns:repeat(5,1fr);gap:.5rem;display:grid}.box-cell{text-align:center;border:1px solid var(--border);border-radius:.4rem;padding:.75rem .25rem}.box-count{font-family:var(--font-display);font-size:1.5rem;display:block}.box-label{font-family:var(--font-mono);color:var(--text-muted);font-size:.7rem}.session-list{gap:.4rem;font-size:.925rem;display:grid}.session-list li{border-bottom:1px solid var(--border);grid-template-columns:6.5rem 1fr auto;gap:1rem;padding:.4rem 0;display:grid}.session-list li:last-child{border-bottom:0}.hub-grid{gap:.75rem;display:grid}@media (width>=48rem){.hub-grid{grid-template-columns:1fr 1fr}}.hub-card{border:1px solid var(--border);background:var(--bg-raised);height:100%;color:var(--text);border-radius:.5rem;padding:1.25rem 1.35rem;text-decoration:none;transition:border-color .15s;display:block}.hub-card:hover{border-color:var(--accent);color:var(--text)}.hub-card h2{margin-top:.4rem;font-size:1.25rem}.hub-card p{color:var(--text-muted);margin-top:.5rem;font-size:.95rem;line-height:1.6}.hub-section{margin-top:2.5rem}.hub-section h2{margin-bottom:1rem;font-size:1.35rem}.quiz-links{gap:.5rem;display:grid}@media (width>=40rem){.quiz-links{grid-template-columns:1fr 1fr}}.quiz-link{border:1px solid var(--border);background:var(--bg-raised);color:var(--text);border-radius:.4rem;align-items:baseline;gap:.75rem;padding:.75rem 1rem;text-decoration:none;display:flex}.quiz-link:hover{border-color:var(--accent);color:var(--text)}.quiz-link .mono{color:var(--accent);font-size:.8rem}.quiz-link small{color:var(--text-muted);font-family:var(--font-mono);white-space:nowrap;margin-left:auto;font-size:.75rem}