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.meter{height:4px}.session-text{font-size:12.5px;color:var(--fg)}.session-text b{font-weight:600}.session-text .dim{color:var(--fg-subtle)}#study{display:flex;flex-direction:column;gap:16px}.stage{perspective:1800px;position:relative;padding-bottom:14px}.stage:before,.stage:after{content:"";position:absolute;left:0;right:0;bottom:14px;height:60%;border-radius:14px;background:var(--surface);border:1px solid var(--line);box-shadow:var(--shadow-xs);transition:opacity .2s ease,transform .25s var(--ease-out)}.stage:before{transform:translateY(7px) scaleX(.965);z-index:0}.stage:after{transform:translateY(14px) scaleX(.93);z-index:-1;opacity:.7}.stage[data-stack="1"]:after,.stage[data-stack="0"]:after{opacity:0;transform:translateY(7px) scaleX(.965)}.stage[data-stack="0"]:before{opacity:0;transform:none}.flash{display:grid;cursor:pointer;position:relative;z-index:1;transform-style:preserve-3d;transition:transform .5s 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.q{font-size:14px;font-weight:500;color:var(--fg-muted);margin-top:6px;letter-spacing:0}.lbl{font-size:11.5px;letter-spacing:.06em;text-transform:uppercase;color:var(--fg-subtle);font-weight:600;margin-top:6px}.a{font-size:clamp(15px,2vw,17px);line-height:1.65;max-width:64ch;text-wrap:pretty}.tip{display:flex;gap:10px;align-items:flex-start;background:var(--warning-soft);color:var(--fg);border-radius:var(--radius-sm);padding:10px 12px;font-size:13.5px;line-height:1.55}.tip svg{width:16px;height:16px;flex:none;color:var(--warning);margin-top:2px}.front .tip{animation:fade-in .2s ease}.spacer{flex:1}.hint-row{display:flex;flex-wrap:wrap;gap:8px;align-items:center;justify-content:space-between}.hint-row .btn{margin-left:-10px}.hint-row .subtle{font-size:12.5px}.answer{min-height:92px;display:flex;flex-direction:column;justify-content:flex-start}.reveal-row{display:grid;grid-template-columns:auto minmax(0,1fr);gap:8px}.reveal{width:100%;--h: 52px;font-size:15px}.skip{--h: 52px;font-size:14px;color:var(--fg-muted);padding:0 18px}.skip kbd{margin-left:6px;background:transparent;border-color:currentColor;color:inherit;opacity:.55}.grade-skip{align-self:center;font-size:12.5px;color:var(--fg-subtle);font-weight:500;padding:4px 8px}@media(hover:hover)and (pointer:fine){.grade-skip:hover{color:var(--fg);text-decoration:underline;text-underline-offset:2px}}.reveal kbd,.grade kbd{margin-left:6px;background:transparent;border-color:currentColor;color:inherit;opacity:.55}.grade{display:flex;flex-direction:column;gap:10px}.grade:not([hidden]){animation:fade-in .15s ease}.grade-q{font-size:14px;font-weight:600;text-align:center}.grade-btns{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px}.grade-btns .btn{--h: 56px;flex-wrap:wrap;align-content:center;column-gap:0;row-gap:1px;border-color:transparent;position:relative}.g-label{font-size:15px;font-weight:650}.g-sub{flex-basis:100%;text-align:center;font-size:11.5px;font-weight:500;opacity:.8}.grade-btns kbd{position:absolute;top:7px;right:8px;margin:0}.g-no{background:color-mix(in srgb,var(--m-again) 11%,var(--surface));color:var(--danger)}@media(hover:hover)and (pointer:fine){.g-no:hover{background:color-mix(in srgb,var(--m-again) 18%,var(--surface))}}.g-part{background:var(--warning-soft);color:var(--warning)}@media(hover:hover)and (pointer:fine){.g-part:hover{background:color-mix(in srgb,var(--m-partial) 22%,var(--surface))}}.g-yes{background:var(--success-soft);color:var(--success)}@media(hover:hover)and (pointer:fine){.g-yes:hover{background:color-mix(in srgb,var(--m-known) 20%,var(--surface))}}.keys{font-size:12.5px;color:var(--fg-subtle);text-align:center}.done{padding:36px 24px 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.page-desc{font-size:12.5px}.answer{position:sticky;bottom:0;z-index:5;min-height:0;margin:0 -16px;padding:10px 16px calc(10px + env(safe-area-inset-bottom,0px));background:linear-gradient(to bottom,transparent,var(--canvas) 14px)}.grade-q{font-size:13px}.grade-btns .btn{--h: 60px}#study{gap:8px}.face{min-height:min(56dvh,440px);padding:18px 18px 20px}}@media(max-width:560px){.grade-btns{gap:6px}.grade-btns kbd,.reveal kbd,.skip kbd,.keys{display:none}.skip{padding:0 14px}.g-sub{font-size:11px}.hint-row .subtle{display:none}.done-actions{flex-direction:column;width:100%}.done-actions .btn{width:100%}}.badge.st-again{color:var(--danger);background:color-mix(in srgb,var(--m-again) 10%,transparent);border-color:transparent}.badge.st-partial{color:var(--warning);background:var(--warning-soft);border-color:transparent}.chip-teil{color:var(--c);background:color-mix(in srgb,var(--c) 10%,transparent);border-color:transparent}.figure{margin:2px 0 0;min-width:0;max-width:100%}.figure pre{margin:0;padding:12px 14px;overflow-x:auto;overscroll-behavior-x:contain;background:var(--sunken);border:1px solid var(--line);border-radius:var(--radius-sm);font:450 13px/1.5 var(--mono);font-variant-ligatures:none;-moz-tab-size:4;tab-size:4;white-space:pre;color:var(--fg);cursor:text;user-select:text;-webkit-user-select:text}.figure pre:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.figure-details{font-size:13px;color:var(--fg-muted)}.figure-details summary{cursor:pointer;width:fit-content;font-weight:550;padding:2px 0}.figure-details[open] summary{margin-bottom:6px}.figure-details .figure pre{font-size:12px}@media(max-width:560px){.figure pre{font-size:12px;padding:10px 12px}}.badge-link{color:inherit;text-decoration:none}.badge-link:hover{border-color:var(--accent);color:var(--accent)}