:root{
--bg:#f5f7fc;--card:#fff;--ink:#27304a;--muted:#5d6785;--line:#e3e8f3;
--lav:#e9e5fb;--lav2:#cfc6f5;--lavd:#5b51a3;--mint:#dff5ec;--mintd:#1f7a58;--sky:#e1effc;--skyd:#2c6aa0;
--peach:#fdeee6;--peachd:#a5552c;--rose:#fbe8ef;--rosed:#9b3b62;--yel:#fff6d6;--yeld:#8a6a10;
--r:14px;--sh:0 1px 2px rgba(30,40,80,.06),0 4px 14px rgba(30,40,80,.06);
--font:Rubik,system-ui,-apple-system,"Segoe UI",Arial,sans-serif}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;font-family:var(--font);color:var(--ink);background:var(--bg);line-height:1.5;overflow-x:hidden}
h1,h2,h3{line-height:1.25;margin:0}
button,input,select{font:inherit;color:inherit}
a{color:var(--skyd)}
:focus-visible{outline:3px solid #8b7fe0;outline-offset:2px;border-radius:6px}
.skip{position:absolute;right:-999px;top:0;background:#fff;padding:8px 12px;z-index:99}.skip:focus{right:8px}
[hidden]{display:none!important}
.muted{color:var(--muted);font-weight:400}
.pill{display:inline-grid;place-items:center;min-width:22px;height:22px;padding:0 6px;border-radius:11px;background:var(--lavd);color:#fff;font-size:12.5px;font-weight:600}
/* top bar */
.topbar{position:sticky;top:0;z-index:30;background:rgba(255,255,255,.92);backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
.topbar-in{max-width:1500px;margin:0 auto;display:flex;align-items:center;gap:12px;padding:8px 16px;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:var(--ink);margin-inline-end:auto;min-width:0}
.lights{display:grid;gap:3px;background:#3b3566;padding:5px 6px;border-radius:9px}
.lights i{display:block;width:9px;height:9px;border-radius:50%}
.lights i:nth-child(1){background:#f7a8b8}.lights i:nth-child(2){background:#ffe08a}.lights i:nth-child(3){background:#9ee6c3}
.brand-t{font-weight:700;font-size:20px;display:flex;align-items:baseline;gap:8px;flex-wrap:wrap}
.brand-t small{font-weight:500;font-size:13px;color:var(--muted)}
.tabs{display:flex;gap:4px;flex-wrap:wrap}
.tab{white-space:nowrap;border:0;background:transparent;padding:8px 12px;border-radius:10px;cursor:pointer;font-weight:500;min-height:40px;display:inline-flex;align-items:center;gap:6px}
.tab:hover{background:var(--lav)}
.tab[aria-current="page"]{background:var(--lav);color:var(--lavd);font-weight:600}
/* buttons */
.btn{border:1px solid transparent;border-radius:11px;padding:9px 14px;min-height:42px;cursor:pointer;font-weight:500;display:inline-flex;align-items:center;justify-content:center;gap:6px;text-decoration:none;line-height:1.2;white-space:nowrap}
.btn.primary{background:var(--lavd);color:#fff}.btn.primary:hover{background:#4a4190}
.btn.soft{background:#fff;border-color:var(--lav2);color:var(--lavd)}.btn.soft:hover{background:var(--lav)}
.btn.ok{background:var(--mint);color:var(--mintd);border-color:#bfe9d6}.btn.ok:hover{background:#cdeedf}
.btn.again{background:var(--lav);color:var(--lavd);border-color:var(--lav2)}
.btn.wide{width:100%}
.btn:disabled{opacity:.5;cursor:not-allowed}
.link-btn{background:none;border:0;color:var(--lavd);text-decoration:underline;cursor:pointer;padding:6px;min-height:36px}
.icon-btn{background:#fff;border:1px solid var(--line);border-radius:10px;width:40px;height:40px;cursor:pointer;font-size:16px;flex:none}
.icon-btn:hover{background:var(--lav)}
.chk{display:inline-flex;align-items:center;gap:7px;cursor:pointer;min-height:32px}
.chk input{width:18px;height:18px;accent-color:var(--lavd)}
/* hero */
.view{max-width:1500px;margin:0 auto;padding:0 16px}
.hero{padding:30px 0 18px;text-align:center}
.hero h1{font-size:clamp(24px,3.4vw,38px);font-weight:700}
.hero-sub{color:var(--muted);margin:8px auto 18px;max-width:680px;font-size:16px}
.hero-sub b{color:var(--lavd)}
.search{max-width:680px;margin:0 auto;position:relative}
.search svg{position:absolute;right:14px;top:50%;transform:translateY(-50%);color:var(--muted)}
.search input{width:100%;border:2px solid var(--lav2);border-radius:14px;padding:13px 46px 13px 14px;font-size:16px;background:#fff;box-shadow:var(--sh)}
.search input:focus{outline:none;border-color:var(--lavd)}
/* layout */
.bank{display:grid;grid-template-columns:290px minmax(0,1fr);gap:20px;align-items:start;padding-bottom:30px}
.filters{position:sticky;top:70px;max-height:calc(100vh - 84px);overflow:auto;background:#fff;border:1px solid var(--line);border-radius:var(--r);padding:12px 14px;box-shadow:var(--sh);overscroll-behavior:contain}
.filters-head{display:flex;align-items:center;gap:8px;margin-bottom:4px}.filters-head h2{font-size:18px;margin-inline-end:auto}
.close-filters.icon-btn,.filters-foot,.open-filters{display:none}
.facet{border-top:1px solid var(--line);padding:10px 0}
.facet>h3{font-size:14.5px;font-weight:600;margin-bottom:8px;display:flex;justify-content:space-between;align-items:center}
.opts{display:flex;flex-wrap:wrap;gap:6px}
.opt{border:1px solid var(--line);background:#fff;border-radius:999px;padding:6px 11px;cursor:pointer;font-size:14px;min-height:36px;display:inline-flex;align-items:center;gap:5px}
.opt .n{color:var(--muted);font-size:12px}
.opt[aria-pressed="true"]{background:var(--lav);border-color:var(--lavd);color:var(--lavd);font-weight:600}
.opt:disabled{opacity:.4;cursor:default}
.tlist{list-style:none;margin:0;padding:0;display:grid;gap:2px}
.trow{display:flex;align-items:center;gap:4px}
.tbtn{flex:1;text-align:right;border:0;background:none;padding:6px 8px;border-radius:9px;cursor:pointer;display:flex;gap:6px;align-items:center;min-height:36px;font-size:14px}
.tbtn:hover{background:var(--bg)}
.tbtn .box{width:18px;height:18px;border:2px solid var(--lav2);border-radius:5px;flex:none;display:grid;place-items:center;font-size:12px;color:#fff}
.tbtn[aria-pressed="true"] .box{background:var(--lavd);border-color:var(--lavd)}
.tbtn[aria-pressed="true"]{color:var(--lavd);font-weight:600}
.tbtn .n{margin-inline-start:auto;color:var(--muted);font-size:12px;font-weight:400}
.texp{border:0;background:none;width:32px;height:32px;border-radius:8px;cursor:pointer;color:var(--muted);flex:none}
.texp:hover{background:var(--lav)}
.subs{list-style:none;margin:0 0 4px;padding:0 22px 0 0;display:grid;gap:1px}
.subs .tbtn{font-size:13.5px;min-height:32px;padding:4px 8px}
.yr{display:flex;gap:8px;align-items:center}
.yr select,.pr-pick select,.field input{border:1px solid var(--lav2);border-radius:10px;padding:7px 10px;background:#fff;min-height:40px;max-width:100%}
.yr select{flex:1;min-width:0}
/* results */
.results{min-width:0}
.results-bar{display:flex;align-items:center;gap:10px;flex-wrap:wrap;margin-bottom:8px}
.rcount{margin:0;margin-inline-end:auto;font-size:16px}.rcount b{color:var(--lavd);font-size:20px}
.rbar-actions{display:flex;gap:8px;flex-wrap:wrap}
.active-chips{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:12px}
.achip{background:var(--lav);color:var(--lavd);border:0;border-radius:999px;padding:5px 10px;font-size:13.5px;cursor:pointer;display:inline-flex;gap:6px;align-items:center;min-height:32px}
.achip:hover{background:var(--lav2)}
.achip.clear{background:none;text-decoration:underline}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(272px,1fr));gap:14px}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);box-shadow:var(--sh);padding:14px 14px 12px;display:flex;flex-direction:column;height:300px;position:relative;min-width:0}
.card:hover{border-color:var(--lav2)}
.card .src{display:flex;gap:6px;align-items:center;font-size:12.5px;color:var(--muted);margin-bottom:6px;min-height:22px;overflow:hidden;white-space:nowrap}
.badge{display:inline-block;border-radius:7px;padding:2px 8px;font-size:12px;font-weight:600;white-space:nowrap}
.badge.b{background:var(--peach);color:var(--peachd)}.badge.c{background:var(--sky);color:var(--skyd)}.badge.o{background:var(--mint);color:var(--mintd)}
.card h3{font-size:16px;font-weight:600;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;margin-bottom:6px}
.card h3 button{all:unset;cursor:pointer}
.card h3 button:focus-visible{outline:3px solid #8b7fe0;outline-offset:2px;border-radius:4px}
.card .desc{font-size:14px;color:var(--muted);display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden;margin:0 0 8px}
.chips{display:flex;flex-wrap:wrap;gap:4px;max-height:52px;overflow:hidden;margin-top:auto;margin-bottom:10px}
.chip{font-size:12px;border-radius:7px;padding:2px 7px;background:var(--bg);color:var(--muted);white-space:nowrap;max-width:100%;overflow:hidden;text-overflow:ellipsis}
.chip.g{background:var(--yel);color:var(--yeld);font-weight:600}
.chip.t{background:var(--lav);color:var(--lavd)}
.card .acts{display:flex;gap:8px}
.card .acts .btn{flex:1;min-height:40px;padding:7px 10px;font-size:14.5px}
.btn.inb{background:var(--mint);color:var(--mintd);border-color:#bfe9d6}
.pdot{position:absolute;top:12px;left:12px;font-size:12px;border-radius:999px;padding:1px 8px;font-weight:600}
.pdot.ok{background:var(--mint);color:var(--mintd)}.pdot.again{background:var(--lav);color:var(--lavd)}
.more-wrap{text-align:center;margin:18px 0}
.empty{color:var(--muted);text-align:center;padding:30px 10px}.empty.small{padding:16px 6px}
/* modal & drawer */
.modal,.drawer{position:fixed;inset:0;z-index:50;display:flex;align-items:center;justify-content:center}
.modal-back{position:absolute;inset:0;background:rgba(25,30,60,.42)}
.modal-box{position:relative;background:#fff;border-radius:18px;width:min(940px,calc(100vw - 24px));max-height:calc(100dvh - 24px);display:flex;flex-direction:column;box-shadow:0 20px 60px rgba(20,25,60,.3)}
.modal-head{display:flex;align-items:flex-start;gap:10px;padding:14px 16px;border-bottom:1px solid var(--line)}
.modal-head h2{font-size:18px;margin-inline-end:auto;padding-top:6px}
.modal-body{overflow:auto;padding:14px 16px 20px;overscroll-behavior:contain}
.drawer{justify-content:flex-start}
.drawer-box{position:relative;background:#fff;width:min(460px,100vw);height:100dvh;display:flex;flex-direction:column;box-shadow:-10px 0 40px rgba(20,25,60,.2)}
.drawer-body{overflow:auto;padding:12px 16px;flex:1}
.drawer-foot{border-top:1px solid var(--line);padding:12px 16px 56px;display:flex;flex-wrap:wrap;gap:8px}
.drawer-foot .btn{flex:1 1 40%}
.field{display:grid;gap:4px;margin-bottom:12px;font-size:14px}.field input{width:100%}
.blist{list-style:none;margin:0;padding:0;display:grid;gap:8px;counter-reset:b}
.blist li{display:flex;align-items:center;gap:6px;border:1px solid var(--line);border-radius:12px;padding:8px;background:#fff;counter-increment:b}
.blist li::before{content:counter(b);font-weight:700;color:var(--lavd);width:22px;text-align:center;flex:none}
.blist li.drag{opacity:.5}
.blist .bt{flex:1;font-size:14px;min-width:0;cursor:pointer;background:none;border:0;text-align:right;padding:2px}
.blist .bt small{display:block;color:var(--muted);font-size:12px}
.blist .icon-btn{width:34px;height:34px;font-size:14px}
.share-out{flex-basis:100%;font-size:13px;background:var(--mint);color:var(--mintd);border-radius:10px;padding:8px 10px;margin:0;word-break:break-all}
/* item detail */
.meta-row{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:10px}
.summary{background:var(--bg);border-radius:12px;padding:10px 12px;margin:0 0 14px;font-size:15px}
.sec-t{font-size:16px;font-weight:700;margin:16px 0 8px;display:flex;align-items:center;gap:8px}
.doc{border:1px solid var(--line);border-radius:12px;background:#fff;overflow:hidden;min-height:80px;position:relative}
.doc .doc-in{padding:10px;overflow-x:auto}
.doc img.qimg{display:block;max-width:100%;height:auto;margin:0 auto}
.doc canvas{direction:ltr;display:block;height:auto;margin:0 auto 8px}
.doc .pg{display:block;height:auto;margin:0 auto 8px}
.doc iframe{display:block;width:100%;height:70vh;border:0}
.doc .loading{padding:24px;text-align:center;color:var(--muted)}
.doc .doc-foot{display:flex;justify-content:space-between;gap:8px;border-top:1px solid var(--line);padding:6px 10px;font-size:12.5px;color:var(--muted);background:#fbfcff;flex-wrap:wrap}
.doc .err{padding:16px;text-align:center}
.docx-body{direction:rtl}
.docx-body section.docx,.docx-body .docx{padding:4px !important;width:auto !important;min-height:0 !important;box-shadow:none !important;margin:0 !important;background:#fff}
.docx-body img{max-width:100%;height:auto}
.docx-body table{max-width:100%}
.docx-body math{font-size:1.05em}
details.sol{border:1px solid var(--lav2);border-radius:12px;margin-top:14px;background:#fbfaff}
details.sol>summary{cursor:pointer;padding:12px 14px;font-weight:600;color:var(--lavd);list-style:none;display:flex;align-items:center;gap:8px;min-height:44px}
details.sol>summary::-webkit-details-marker{display:none}
details.sol>summary::before{content:"▸";transition:transform .2s}
details.sol[open]>summary::before{transform:rotate(90deg)}
details.sol>.sol-in{padding:0 10px 12px}
.extras{display:grid;gap:8px}
.extra{display:flex;gap:8px;align-items:center;flex-wrap:wrap;border:1px solid var(--line);border-radius:10px;padding:8px 10px;background:#fff}
.extra span{flex:1;min-width:150px;font-size:14px}
.orig{display:inline-flex;margin-top:16px}
.m-acts{display:flex;gap:8px;flex-wrap:wrap;margin:6px 0 4px}
.kv{font-size:13.5px;color:var(--muted);margin:2px 0}
/* practice */
.pr-head{display:flex;flex-wrap:wrap;gap:12px;align-items:flex-end;padding:22px 0 10px}
.pr-head>div:first-child{margin-inline-end:auto}
.pr-title{font-size:clamp(22px,3vw,30px)}
.pr-sub{color:var(--muted);margin:4px 0 0}
.pr-pick{display:flex;gap:8px;flex-wrap:wrap}
.pr-pick label{display:grid;font-size:12.5px;color:var(--muted);gap:2px}
.pr-pick select{max-width:220px}
.pr-progress{display:flex;align-items:center;gap:14px;flex-wrap:wrap;margin-bottom:12px}
.pr-progress p{margin:0;font-size:14px;color:var(--muted)}
.bar{flex:1 1 220px;height:10px;background:#e8ebf4;border-radius:6px;overflow:hidden;display:flex}
.bar i{display:block;height:100%}#prBarOk{background:#7fd6ae}#prBarAgain{background:#b8acf0}
.pr-card{background:#fff;border:1px solid var(--line);border-radius:18px;box-shadow:var(--sh);padding:16px;margin-bottom:40px}
.pr-top{display:flex;gap:10px;flex-wrap:wrap;align-items:center;margin-bottom:8px}
.pr-top h2{font-size:18px;margin-inline-end:auto}
.pr-steps{display:flex;gap:8px;flex-wrap:wrap;margin:14px 0 4px;align-items:center}
.pr-hint{background:var(--yel);color:var(--yeld);border-radius:10px;padding:8px 12px;font-size:14px;margin:0}
.pr-nav{display:flex;gap:8px;flex-wrap:wrap;justify-content:space-between;border-top:1px solid var(--line);margin-top:16px;padding-top:12px}
.reveal{animation:rv .35s ease}
@keyframes rv{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}
/* set */
.set-head{padding:24px 0 16px}.kicker{color:var(--lavd);font-weight:600;margin:0 0 4px}
.set-head h1{font-size:clamp(22px,3vw,32px)}.set-head p{color:var(--muted)}
.set-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:10px}
#view-set .grid{padding-bottom:40px}
/* about */
.about{max-width:820px;padding-top:24px;padding-bottom:40px}
.about h1{font-size:28px;margin-bottom:12px}.about h2{font-size:19px;margin:22px 0 8px}
.about li{margin-bottom:6px}
/* print */
.print-tools{display:flex;flex-wrap:wrap;gap:10px;align-items:center;padding:14px 0;position:sticky;top:57px;background:var(--bg);z-index:5}
.pstatus{color:var(--muted);font-size:14px;margin-inline-end:auto}
.sheet{background:#fff;border:1px solid var(--line);border-radius:12px;padding:24px;margin-bottom:40px;max-width:900px}
.ws-head{border-bottom:2px solid var(--ink);padding-bottom:10px;margin-bottom:14px}
.ws-head h1{font-size:24px}
.ws-line{display:flex;gap:30px;margin-top:8px;font-size:15px;flex-wrap:wrap}
.ws-q{margin:0 0 22px;break-inside:auto}
.ws-q h2{font-size:16px;margin:0 0 6px;display:flex;gap:8px}
.ws-q h2 .num{background:var(--ink);color:#fff;border-radius:7px;min-width:28px;text-align:center;padding:0 6px}
.ws-q h2 small{font-weight:400;color:var(--muted);font-size:12.5px;align-self:center}
.ws-q .doc{border:0}.ws-q .doc .doc-foot{display:none}
.ws-src{font-size:11.5px;color:var(--muted);margin:2px 0 0;word-break:break-all}
.ws-sol-head{break-before:page;page-break-before:always;border-top:2px dashed var(--line);padding-top:18px;margin-top:18px}
.toast{position:fixed;bottom:60px;left:50%;transform:translateX(-50%);background:#2a2350;color:#fff;padding:10px 16px;border-radius:12px;z-index:60;font-size:14.5px;max-width:calc(100vw - 32px);box-shadow:var(--sh)}
/* responsive */
@media (max-width:900px){
 .bank{grid-template-columns:minmax(0,1fr)}
 .open-filters{display:inline-flex}
 .filters{position:fixed;inset:0 0 0 auto;width:min(380px,100vw);max-height:none;height:100dvh;border-radius:0;z-index:45;transform:translateX(105%);transition:transform .25s;top:0;padding-bottom:0;display:flex;flex-direction:column}
 #facets{flex:1;overflow:auto}
 .filters.open{transform:none;box-shadow:-10px 0 40px rgba(20,25,60,.25)}
 .close-filters.icon-btn{display:block}.filters-foot{display:block;padding:10px 0 50px;background:#fff}
 body.filters-open::after{content:"";position:fixed;inset:0;background:rgba(25,30,60,.4);z-index:44}
}
@media (max-width:560px){
 .topbar-in{padding:6px 10px;gap:6px}
 .brand-t small{display:none}.brand-t{font-size:18px}
 .tabs{width:100%;justify-content:space-between}
 .tab{padding:6px 4px;font-size:14px;flex:1 1 auto;justify-content:center;gap:4px}
 .tab .pill{min-width:20px;height:20px;font-size:12px}
 .view{padding:0 12px}
 .hero{padding:18px 0 12px}
 .rbar-actions{width:100%}.rbar-actions .btn{flex:1}
 #addAllBtn{display:none}
 .card{height:290px}
 .modal-box{width:100vw;max-height:100dvh;height:100dvh;border-radius:0}
 .print-tools{top:94px}
 .sheet{padding:14px}
 .pr-pick{width:100%}.pr-pick label{flex:1 1 45%}.pr-pick select{max-width:none;width:100%}
 .pr-card{padding:12px}
}
@media (prefers-reduced-motion:reduce){*{animation:none!important;transition:none!important;scroll-behavior:auto!important}}
@media print{
 @page{margin:14mm}
 body{background:#fff}
 .topbar,.no-print,.toast,.modal,.drawer,#view-bank,#view-practice,#view-set,#view-about{display:none!important}
 #view-print{display:block!important;max-width:none;padding:0}
 .sheet{border:0;padding:0;margin:0;max-width:none}
 .ws-q.brk{break-before:page;page-break-before:always}
 .ws-q.brk:first-of-type{break-before:auto}
 .doc{border:0}.doc .doc-in{overflow:visible;padding:0}
 canvas,img{break-inside:avoid}
}