.container{max-width:1200px;margin:0 auto;padding:0 24px}.page-header{background-color:var(--color-canvas);border-bottom:1px solid var(--color-hairline);padding:64px 0 32px}.eyebrow{font-family:var(--font-mono);font-size:12px;color:var(--color-mute);text-transform:uppercase;letter-spacing:.08em;margin:0 0 12px}.page-title{font-size:40px;font-weight:600;line-height:1.05;letter-spacing:-1.6px;color:var(--color-ink);margin:0 0 12px}.page-desc{font-size:16px;line-height:24px;color:var(--color-body);margin:0 0 24px;max-width:520px}.filter-row{display:flex;flex-wrap:wrap;gap:16px;align-items:center}.filter-group{display:flex;gap:6px;flex-wrap:wrap}.filter-pill,.diff-pill{height:32px;padding:0 14px;background-color:var(--color-canvas-soft);border:1px solid var(--color-hairline);border-radius:9999px;font-size:13px;font-weight:400;color:var(--color-body);cursor:pointer;transition:background-color .15s,color .15s,border-color 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.streak-card--active{background:linear-gradient(135deg,#1c1108,#1a1a1a)}.streak-main{display:flex;align-items:baseline;gap:4px;margin-bottom:12px}.streak-flame{font-size:20px;line-height:1;margin-right:2px}.streak-count{font-size:28px;font-weight:600;letter-spacing:-1px;color:var(--color-ink);line-height:1}.streak-unit{font-size:14px;font-weight:500;color:var(--color-mute)}.streak-stats{display:flex;gap:16px;padding-top:10px;border-top:1px solid var(--color-hairline)}.streak-stat{display:flex;flex-direction:column;gap:1px}.streak-stat-label{font-family:var(--font-mono);font-size:10px;color:var(--color-mute);text-transform:uppercase;letter-spacing:.06em}.streak-stat-value{font-family:var(--font-mono);font-size:13px;font-weight:600;color:var(--color-body)}.reset-btn{width:100%;height:34px;background-color:transparent;color:var(--color-mute);border:1px solid var(--color-hairline);border-radius:6px;font-size:12px;font-weight:500;cursor:pointer;transition:color .15s,border-color .15s,background-color .15s}.reset-btn:hover{color:var(--color-error-text);border-color:var(--color-error-border);background-color:var(--color-error-bg)}.sidebar-link{display:block;padding:12px 16px;background-color:var(--color-canvas);border:1px solid var(--color-hairline);border-radius:8px;font-size:14px;font-weight:500;color:var(--color-body);text-decoration:none;transition:color .15s,border-color .15s}.sidebar-link:hover{color:var(--color-ink);border-color:var(--color-hairline-strong)}@media(max-width:960px){.practice-layout{grid-template-columns:1fr}.sidebar{display:grid;grid-template-columns:1fr 1fr}}@media(max-width:600px){.page-title{font-size:30px}.page-header{padding:40px 0 24px}.question-card{padding:20px}.sidebar{grid-template-columns:1fr}.filter-row{flex-direction:column;align-items:flex-start;gap:10px}.choice-card{padding:12px 14px;gap:10px}.choice-letter{width:24px;height:24px;font-size:11px}.question-text{font-size:15px;line-height:24px}.section{padding:32px 0 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