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.focus-filter{margin-inline:var(--space-4);flex:1;position:static;top:auto}.focus-filter__item,.focus-chip{cursor:pointer;font:inherit;border:1px solid #0000;border-radius:999px}.focus-filter__item{color:var(--color-muted);background:0 0;flex:auto;min-height:2.35rem;padding:0 .7rem}.focus-filter__item[aria-pressed=true]{background:var(--color-surface);color:var(--color-ink);box-shadow:0 1px 4px #20201e1a}.focus-cloud{padding-bottom:calc(var(--control-height) + var(--space-7));align-content:flex-start}.focus-chip{background:var(--color-subtle);border:1px solid var(--color-line);color:var(--color-ink);min-height:2.4rem;padding:.35rem .8rem}.focus-chip--focused{background:var(--color-ink);border-color:var(--color-ink);color:var(--color-surface)}.focus-chip--in-course{color:#286b5d;background:#e7f2ef;border-color:#b9d8d0}.focus-chip--new{background:var(--color-surface)}.onboarding-create{bottom:calc(4.625rem + env(safe-area-inset-bottom) + var(--space-4));width:min(calc(100% - (2 * 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var(--color-accent-soft);transform:translateY(-2px)scale(1.14)}45%{background:var(--color-accent-soft);box-shadow:0 0 0 .25rem var(--color-accent-soft);transform:translateY(0)scale(1.04)}to{background:0 0;transform:none;box-shadow:0 0 #0000}}.visually-hidden,.visually-hidden-action{clip:rect(0 0 0 0)!important;clip-path:inset(50%)!important;white-space:nowrap!important;border:0!important;width:1px!important;height:1px!important;margin:-1px!important;padding:0!important;position:absolute!important;overflow:hidden!important}@keyframes checking-spin{to{transform:rotate(360deg)}}@media (prefers-reduced-motion:reduce){.checking-spinner,.mobile-header-refresh.is-refreshing>svg{animation-duration:1.4s}}.learning-controls--compact{padding:var(--space-5) var(--space-5) calc(5.5rem + env(safe-area-inset-bottom))}.learning-section-title{color:var(--color-ink);font-size:var(--type-body);font-weight:var(--weight-light);margin:0 0 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var(--shell-width));border:0;border-radius:1.5rem 1.5rem 0 0}.report-dialog__ticket-row{align-items:center;gap:var(--space-3);justify-content:space-between;display:flex}.report-dialog__label{color:var(--color-muted);font-size:var(--type-label);font-weight:var(--weight-light);margin:0 0 var(--space-2)}.report-ticket{font-size:.875rem;font-weight:var(--weight-light);white-space:nowrap}.report-copy-action{width:2.375rem;height:2.375rem}.report-copy-action:disabled{opacity:.35}.report-comment{color:var(--color-ink);resize:none;background:0 0;border:1px solid #c9c4bc;border-radius:.875rem;width:100%;min-height:6.5rem;margin-top:1.125rem;padding:.8125rem .875rem;line-height:1.45}.frontier-empty-screen{min-height:calc(100dvh - 8.375rem - env(safe-area-inset-bottom));padding:2.125rem var(--space-5) 7rem;flex-direction:column;display:flex}.home-shell .home-content:has(.frontier-empty-screen){max-width:var(--content-width);width:100%;margin:0 auto}.frontier-empty-screen h1{margin:0 0 var(--space-5);font-size:1.25rem;font-weight:500;line-height:1.3}.frontier-filter-strip{margin-bottom:1.125rem}.frontier-focus-cloud button{cursor:pointer;min-height:2.5rem}.frontier-primary-action{width:min(100%, calc(var(--content-width) + (2 * var(--space-5))));max-width:var(--shell-width);z-index:15;position:fixed;left:50%;transform:translate(-50%)}.learning-control-overlay,.mobile-progress-overlay,.answer-sheet-backdrop,.checking-overlay,.topics-overlay{width:min(100%, var(--shell-width));left:50%;right:auto;transform:translate(-50%)}@media (width>=26.9375rem){body{background:#efefec}.auth-shell,.centered-shell,.lesson-shell,.design-system-shell,.mobile-learning-page,.practice-shell{background:var(--color-canvas);box-shadow:0 0 0 1px #20201e0d}}@media (width<=340px){.learning-controls--compact,.practice-content,.frontier-empty-screen,.focus-picker--page{padding-left:var(--space-4);padding-right:var(--space-4)}}