@font-face{font-family:"El Messiri";src:url(../fonts/ElMessiri-Regular.ttf);font-weight:400;font-display:swap}
@font-face{font-family:"El Messiri";src:url(../fonts/ElMessiri-Bold.ttf);font-weight:700;font-display:swap}
:root{
  --bg:#f3f8f9; --card:#fff; --ink:#14262c; --muted:#5c7178; --line:#d5e3e7;
  --brand:#16798f; --brand-2:#7ab530; --brand-ink:#fff; --accent:#e4f2f5;
  --ok:#1d8a4a; --ok-bg:#e3f5ea; --bad:#c0392b; --bad-bg:#fbe9e7;
}
@media (prefers-color-scheme:dark){
  :root{--bg:#0e1a1e;--card:#162429;--ink:#e6f1f3;--muted:#92a9b0;--line:#25393f;--brand:#3fb0c9;--brand-ink:#06161a;--accent:#1b2f35;--ok:#5fd18a;--ok-bg:#15301f;--bad:#ff8a7a;--bad-bg:#3a1e1b}
}
*{box-sizing:border-box}
[hidden]{display:none!important}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:17px/1.75 "El Messiri",system-ui,-apple-system,"Segoe UI",Tahoma,sans-serif}
a{color:var(--brand);text-decoration:none}
button{font:inherit;color:inherit}
.bar{position:sticky;top:0;z-index:5;display:flex;align-items:center;gap:10px;padding:8px 16px;padding-top:max(8px,env(safe-area-inset-top));background:linear-gradient(90deg,#16798f,#4aa35a);color:#fff}
.brand{display:flex;align-items:center;gap:8px;color:#fff;font-weight:700;font-size:20px;white-space:nowrap}
.brand img{border-radius:8px;background:#fff}
.icon-btn{background:transparent;border:0;color:#fff;font-size:24px;line-height:1;padding:6px 8px;cursor:pointer}
#q{flex:1;min-width:0;border:0;border-radius:20px;padding:8px 14px;font:inherit;font-size:15px;background:rgba(255,255,255,.95);color:#14262c}
.crumbs{display:flex;flex-wrap:wrap;gap:2px 8px;max-width:960px;margin:0 auto;padding:10px 16px 0;font-size:14px;color:var(--muted)}
.crumbs:empty{display:none}
.crumbs a::after{content:"›";margin-inline-start:8px;color:var(--muted)}
.crumbs span{color:var(--ink)}
main{max-width:960px;margin:0 auto;padding:12px 16px 40px}
h1{font-size:24px;line-height:1.4;margin:12px 0}
h2{font-size:19px;margin:22px 0 8px}
.muted{color:var(--muted)}
.hero{display:flex;align-items:center;gap:16px;background:var(--card);border:1px solid var(--line);border-radius:16px;padding:14px 16px;margin:8px 0 16px}
.hero img{width:92px;height:auto;flex:none}
.hero h1{margin:0 0 4px}
.hero p{margin:0}
.chips{display:flex;flex-wrap:wrap;gap:6px;margin-top:8px}
.chip{background:var(--accent);color:var(--brand);border-radius:12px;padding:0 10px;font-size:14px}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(230px,1fr));gap:10px}
.tile,.row{display:block;background:var(--card);border:1px solid var(--line);border-radius:14px;padding:12px 14px;color:var(--ink)}
.tile{border-inline-start:5px solid var(--brand-2)}
.tile:hover,.row:hover,.tile:active,.row:active{background:var(--accent)}
.tile small,.row small{display:block;color:var(--muted);font-size:14px}
.list{display:flex;flex-direction:column;gap:8px}
.row{display:flex;justify-content:space-between;align-items:center;gap:10px}
.row .tags{display:flex;gap:6px;flex:none}
.badge{display:inline-block;background:var(--accent);color:var(--brand);border-radius:10px;padding:0 8px;font-size:13px;white-space:nowrap}
.badge.done{background:var(--ok-bg);color:var(--ok)}
.actions{display:flex;flex-wrap:wrap;gap:8px;margin:14px 0}
.btn{display:inline-block;background:var(--brand);color:var(--brand-ink);border:0;border-radius:12px;padding:9px 18px;cursor:pointer;font-weight:700}
.btn.alt{background:var(--accent);color:var(--brand)}
.btn[disabled]{opacity:.5;cursor:default}
.notice{background:var(--accent);border:1px solid var(--line);border-radius:12px;padding:12px 14px;margin:12px 0}
/* quiz */
.qcard{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:16px}
.qmeta{display:flex;justify-content:space-between;color:var(--muted);font-size:14px;margin-bottom:8px}
.bar-progress{height:6px;background:var(--line);border-radius:3px;overflow:hidden;margin-bottom:12px}
.bar-progress i{display:block;height:100%;background:linear-gradient(90deg,var(--brand),var(--brand-2))}
.qtext{font-size:19px;font-weight:700;margin:0 0 12px;white-space:pre-line}
.qimg{max-width:100%;border-radius:10px;margin:0 0 12px}
.opts{display:flex;flex-direction:column;gap:8px}
.opt{text-align:start;background:var(--bg);border:2px solid var(--line);border-radius:12px;padding:10px 14px;cursor:pointer;white-space:pre-line}
.opt:hover:not([disabled]){border-color:var(--brand)}
.opt.ok{border-color:var(--ok);background:var(--ok-bg)}
.opt.bad{border-color:var(--bad);background:var(--bad-bg)}
.opt[disabled]{cursor:default}
.expl{margin:12px 0 0;padding:10px 12px;border-radius:12px;background:var(--accent);font-size:16px;white-space:pre-line}
.score{font-size:42px;font-weight:700;text-align:center;margin:10px 0;color:var(--brand)}
.foot{text-align:center;color:var(--muted);font-size:13px;padding:20px 16px 30px}
.lesson-video{display:block;width:100%;max-height:70vh;background:#000;border-radius:12px}
.pdf-frame{display:block;width:100%;height:80vh;border:1px solid var(--line);border-radius:12px;background:#fff}
.notice.err{background:var(--bad-bg);border-color:var(--bad);color:var(--bad)}
.notice.err a{color:inherit;text-decoration:underline}
/* zoomable PDF viewer */
.pv{border:1px solid var(--line);border-radius:12px;overflow:hidden;background:var(--card)}
.pv:fullscreen{display:flex;flex-direction:column;border-radius:0;border:0}
.pv:fullscreen .pv-scroll{height:auto;flex:1}
.pv-bar{display:flex;flex-wrap:wrap;align-items:center;gap:6px;padding:8px;background:var(--accent);border-bottom:1px solid var(--line)}
.pv-btn{min-width:40px;height:40px;padding:0 12px;border:0;border-radius:10px;background:var(--brand);color:var(--brand-ink);font-size:18px;font-weight:700;cursor:pointer}
.pv-btn:hover{filter:brightness(1.1)}
.pv-zoom{min-width:52px;text-align:center;font-weight:700;direction:ltr}
.pv-sep{width:1px;height:24px;background:var(--line);margin:0 2px}
.pv-pagein{width:60px;height:40px;text-align:center;border:2px solid var(--line);border-radius:10px;background:var(--bg);color:var(--ink);font:inherit}
.pv-of{color:var(--muted);direction:ltr}
.pv-scroll{height:78vh;overflow:auto;background:#6b7a80;touch-action:pan-x pan-y;-webkit-overflow-scrolling:touch;outline:none}
.pv-pages{width:max-content;min-width:100%;padding:8px 0}
.pv-page{position:relative;margin:8px auto;background:#fff;box-shadow:0 1px 6px rgba(0,0,0,.4)}
.pv-page canvas{display:block;width:100%;height:100%}
/* exam */
.cta{margin-bottom:12px}
.cta-card{display:block;padding:14px 16px;border-radius:14px;color:#fff;background:linear-gradient(90deg,#16798f,#4aa35a);border:0}
.cta-card strong{display:block;font-size:20px}
.cta-card small{display:block;opacity:.9}
.cta-card.orange,.btn.orange{background:#e8820c;color:#fff}
.row.orange{border-inline-start:5px solid #e8820c;background:rgba(232,130,12,.12)}
.tile.big{font-size:20px;padding:18px 16px}
.chips.lens{gap:8px}
.chip-btn{min-width:56px;height:42px;border:2px solid var(--line);border-radius:12px;background:var(--card);color:var(--ink);font:inherit;font-weight:700;cursor:pointer}
.chip-btn.on{border-color:var(--brand);background:var(--accent);color:var(--brand)}
.ex-time{font-weight:700;direction:ltr}
.qcard.urgent .ex-time{color:var(--bad)}
.qcard.urgent .ex-bar i{background:var(--bad)}
.ex-bar i{transition:width .25s linear}
.ex-verdict{margin:12px 0 0;font-weight:700;font-size:18px}
.ex-verdict.good{color:var(--ok)}
.ex-verdict.wrong{color:var(--bad)}
.pct{text-align:center;font-size:26px;font-weight:700}
.pct.pass{color:var(--ok)}
.pct.fail{color:var(--bad)}
.ex-grade{text-align:center;font-size:19px;font-weight:700}
.qcard.rv{margin:12px 0;border-inline-start:5px solid var(--line)}
.qcard.rv.good{border-inline-start-color:var(--ok)}
.qcard.rv.wrong{border-inline-start-color:var(--bad)}
.opt.static{cursor:default}
.row.orange a{flex:1}
.score,.pct{direction:ltr}
/* home: unit illustrations + help card */
.tile.withimg{display:flex;align-items:center;gap:12px}
.tile-img{width:76px;height:auto;flex:none;border-radius:8px;background:#fff}
.tile.withimg span{flex:1}
.cta-card.help{display:flex;align-items:center;gap:12px;background:var(--card);color:var(--ink);border:1px solid var(--line)}
.cta-card.help img{border-radius:10px;flex:none}
.cta-card.help strong{font-size:18px}
/* ---------- visual editor (edit mode only) ---------- */
body.editing{padding-bottom:84px}
body.editing [data-ek]{outline:1px dashed #e8820c;outline-offset:2px;cursor:text;min-width:1.5em;border-radius:3px}
body.editing [data-ek]:hover{background:rgba(232,130,12,.14)}
body.editing [data-ek].ed-active{outline:2px solid #e8820c;background:rgba(232,130,12,.18);cursor:text}
body.editing [data-ik]{outline:2px dashed #1d8a4a;outline-offset:2px;cursor:pointer}
body.editing [data-ik]:hover{filter:brightness(1.08)}
[data-ph]:empty::before{content:attr(data-ph);color:var(--muted);font-style:italic}
body:not(.editing) .expl:empty{display:none}
#ed-ui{position:fixed;z-index:60;left:0;right:0;bottom:0;display:flex;flex-wrap:wrap;gap:6px;align-items:center;padding:8px 10px;padding-bottom:max(8px,env(safe-area-inset-bottom));background:#1f2a33;color:#fff;box-shadow:0 -2px 10px rgba(0,0,0,.35)}
.ed-status{flex:1 1 150px;font-weight:700;font-size:14px}
.ed-status.warn{color:#ffb454}
.ed-btn{min-height:38px;padding:0 12px;border:0;border-radius:10px;background:#3b4a56;color:#fff;font:inherit;font-size:14px;cursor:pointer}
.ed-btn:hover{filter:brightness(1.15)}
.ed-btn[disabled]{opacity:.4;cursor:default}
.ed-btn.primary{background:#1d8a4a}
.ed-btn.danger{background:#b3402f}
.ed-toast{position:absolute;bottom:100%;left:50%;transform:translateX(-50%);margin-bottom:8px;background:#000c;color:#fff;border-radius:10px;padding:8px 14px;font-size:14px;max-width:92vw;text-align:center}
.ed-modal{position:fixed;inset:0;z-index:70;background:rgba(0,0,0,.55);display:flex;align-items:flex-start;justify-content:center;overflow:auto;padding:16px}
.ed-modal-box{background:var(--card);color:var(--ink);border-radius:14px;max-width:720px;width:100%;padding:16px 18px;margin:auto}
.ed-modal-box h2{margin:0 0 8px}
.ed-modal-box h3{margin:16px 0 6px;font-size:16px}
.ed-row{display:flex;flex-wrap:wrap;gap:10px}
.ed-field{display:flex;flex-direction:column;gap:2px;flex:1 1 160px;font-size:14px;margin:4px 0}
.ed-field input{padding:8px 10px;border:2px solid var(--line);border-radius:10px;background:var(--bg);color:var(--ink);font:inherit}
.ed-modal-actions{display:flex;gap:8px;margin-top:14px}
.ed-err{color:var(--bad);font-weight:700;min-height:1.4em}
.qeditor{margin-top:18px}
/* access gate */
body.locked .bar #q{display:none}
.lockbox{max-width:440px;margin:24px auto;text-align:center}
.lockbox h1{margin:4px 0}
.lockinput{width:100%;padding:12px 14px;font:inherit;font-size:18px;letter-spacing:1px;text-align:center;border:2px solid var(--line);border-radius:12px;background:var(--bg);color:var(--ink);margin:8px 0}
.lockinput:focus{outline:none;border-color:var(--brand)}
.lockmsg{min-height:1.5em;color:var(--muted);font-size:15px}
.lockmsg.err{color:var(--bad);font-weight:700}
.linkbtn{background:none;border:0;color:var(--muted);text-decoration:underline;font:inherit;font-size:13px;cursor:pointer}
.gate-foot{padding-top:0}