:root{--ink:#143a55;--navy:#102f4e;--teal:#079c9d;--sub:#57758a;--line:#d7e6ee;--bg:#f4f9fc}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;direction:rtl;background:var(--bg);color:var(--ink);font:16px/1.75 Tahoma,'Noto Sans Arabic','Segoe UI',Arial,sans-serif}button,a{font:inherit}button{cursor:pointer}button:focus-visible,a:focus-visible{outline:3px solid #e9ac42;outline-offset:3px}button:disabled{cursor:default;opacity:.5}a{color:inherit}.wrap{width:min(980px,calc(100% - 24px));margin:auto}.mast{background:linear-gradient(118deg,#09253f,#18506a);padding:15px 0 27px;color:white}.topnav{display:flex;justify-content:space-between;gap:10px;align-items:center}.topnav a{border:1px solid #89adbf;text-decoration:none;color:#e9faff;padding:6px 12px;border-radius:10px;font-weight:800;font-size:13px}.brand{font-weight:900}.brand small{display:block;color:#9be6e0;font-size:10px;font-weight:500;letter-spacing:.09em}.mast h1{font-size:clamp(24px,4vw,34px);margin:19px 0 3px}.mast p{color:#cfe2e9;font-size:13px;margin:0}.main{margin-top:-12px;padding-bottom:30px}.panel{background:#fff;border:1px solid var(--line);border-radius:19px;box-shadow:0 4px 18px #12384a0b;padding:clamp(13px,3vw,25px);margin-bottom:13px}.eyebrow{color:#0b8490;font-size:12px;font-weight:900}.panel h2{font-size:clamp(22px,3.3vw,29px);margin:5px 0 7px}.muted{color:var(--sub);font-size:14px;margin:2px 0 12px}.progressline{height:8px;background:#e8f0f3;border-radius:20px;overflow:hidden;flex:1;min-width:125px}.progressline>i{display:block;background:#0a9a98;height:100%;transition:width .25s}.stats{display:flex;align-items:center;gap:12px;flex-wrap:wrap;color:#567183;font-size:13px;font-weight:700;margin:12px 0}.lesson-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.lesson-link{text-align:right;border:1px solid #d6e6ed;background:#f2fafb;display:flex;flex-direction:column;gap:7px;min-height:170px;padding:18px;border-radius:17px;color:var(--ink)}.lesson-link:nth-child(2n){background:#f5f4fd}.lesson-link strong{font-size:21px}.lesson-link p{color:var(--sub);font-size:13px;margin:0}.lesson-link .emoji{font-size:31px}.lesson-link .start{color:#057a81;font-weight:900;font-size:13px;margin-top:auto}.lesson-link:hover{border-color:#0a9b9c}.btnrow{display:flex;flex-wrap:wrap;gap:9px;margin:17px 0 2px}.btn{border:1px solid #087e89;background:#098d96;color:white;border-radius:11px;min-height:46px;display:inline-flex;align-items:center;justify-content:center;text-align:center;text-decoration:none;padding:9px 15px;font-weight:900}.btn.alt{background:#edf6f8;color:#185773;border-color:#bfd8e2}.btn.soft{background:#f1effe;color:#51498b;border-color:#ddd7f2}.btn:disabled{opacity:.45}.lesson-head{display:flex;justify-content:space-between;gap:10px;align-items:flex-start}.lesson-head h2{margin:5px 0}.lesson-head .btn{font-size:12px;white-space:nowrap;padding:8px}.stages{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;margin:16px 0}.stage{display:flex;flex-direction:column;gap:2px;justify-content:center;align-items:center;min-height:80px;border-radius:13px;border:1px solid #d9e5ee;background:#f6f9fc;color:#517184;padding:7px 3px;text-align:center}.stage .emoji{font-size:22px}.stage span:last-child{font-size:12px;font-weight:900}.stage.active{background:#dff7f3;border-color:#009c97;color:#006e71}.stage:hover{background:#e8f7f7}.stage-title{scroll-margin-top:12px;font-size:20px;margin:12px 0}.lesson-info{padding:12px 15px;border-radius:13px;background:#eef8fb;border:1px solid #cfe5e9;color:#1b536a;margin:10px 0}.lesson-info strong{display:block;color:#0c6d75;font-size:15px}.lesson-info p{margin:4px 0;font-size:15px}.lesson-info.note{background:#fff9ec;border-color:#f1ddb0}.sequence{direction:rtl;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;margin:12px 0;max-width:790px;margin-inline:auto}.sequence-item{background:white;border:1px solid #cbdfe8;border-radius:13px;min-height:92px;padding:7px 4px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:3px;min-width:0}.sequence-item .ord{font:700 11px/1.2 Arial,sans-serif;color:#6c8394}.sequence-item svg{width:100%;max-width:108px;height:72px;display:block}.sequence-item .value{font-size:clamp(17px,4vw,27px);font-weight:900;color:#194761;direction:ltr}.sequence-item.missing{background:#e6f8f5;border:2px dashed #0a9fa3}.sequence-item.missing .value{font-size:34px;color:#0b8a92}.qa-title{font-size:17px;font-weight:900;margin:13px 0 8px;line-height:1.65}.option-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:9px;max-width:790px;margin:11px auto}.opt{position:relative;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;min-height:115px;border:2px solid #d4e5eb;border-radius:14px;background:#fbfdff;padding:8px;color:#153f59;touch-action:manipulation}.opt .letter{position:absolute;top:5px;left:9px;font:800 15px/1.3 Arial,sans-serif;color:#44718a}.opt svg{display:block;width:min(100%,160px);height:84px}.opt .value{font-size:27px;font-weight:900}.opt:hover:not(:disabled){background:#eaf9f7;border-color:#0b8e91}.opt.chosen{background:#eafafa;border-color:#0c88ad}.opt.correct{background:#e7f9ee;border-color:#15905d}.opt.wrong{background:#fff0ee;border-color:#d7655a}.opt:disabled{opacity:1}.feedback{border:1px solid #b7dfca;background:#eafaf1;color:#165d42;border-radius:12px;padding:11px 13px;margin:10px 0;font-size:14px}.feedback.bad{background:#fff3e9;border-color:#efc8a9;color:#8d502c}.feedback strong{display:block}.feedback p{margin:3px 0}.counter{color:#618194;font-size:13px;font-weight:850}.quizsteps{display:flex;flex-wrap:wrap;gap:7px;margin:10px 0}.quizsteps button{border:1px solid #cadce6;border-radius:9px;min-width:44px;min-height:42px;background:#fff;color:#16435a;font-weight:800}.quizsteps button.active{background:#126d88;color:#fff}.quizsteps button.done:not(.active){background:#dff6ee;border-color:#87c7af}.score{font-size:45px;font-weight:900;color:#0b858d;margin:6px 0}.footer{border-top:1px solid #d6e5ec;color:var(--sub);font-size:12px;text-align:center;padding-top:14px}.footer a{color:#057f84;text-decoration:none}.hidden-hint{border:1px solid #bbdce2;background:#f5fafc;border-radius:11px;padding:10px;margin:10px 0}.hidden-hint p{margin:0}.prototype{font-size:12px;color:#567183}
@media(max-width:650px){.lesson-list{grid-template-columns:1fr}.lesson-link{min-height:124px;padding:14px}.lesson-link strong{font-size:18px}.sequence{gap:5px}.sequence-item{min-height:80px;padding:5px 1px}.sequence-item svg{height:64px}.opt{min-height:112px}.opt svg{height:82px}.stage{min-height:72px}.stage .emoji{font-size:19px}.stage span:last-child{font-size:10px}}
@media(max-width:390px){.wrap{width:calc(100% - 12px)}.panel{padding:11px 8px}.sequence{gap:3px}.sequence-item{border-radius:9px}.sequence-item svg{height:59px}.opt{padding:3px;min-height:106px}.option-grid{gap:6px}.stages{gap:4px}.stage{padding:5px 0}.btn{padding:8px 9px;font-size:13px}.lesson-head{flex-wrap:wrap}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.progressline>i{transition:none}}

/* Center the missing item when four given stages form the first row. */
.sequence.q-len-5 .sequence-item.missing{grid-column:2 / span 2;min-height:73px}


/* v1.4.7 advanced patterns unit */
.matrix-board{display:grid;grid-template-columns:repeat(3,minmax(84px,1fr));gap:8px;max-width:420px;margin:12px auto 16px}
.matrix-cell{background:#fff;border:1.6px solid #d7e3ea;border-radius:14px;min-height:110px;display:flex;align-items:center;justify-content:center;padding:6px}
.matrix-cell.missing{background:#f5fbff;border-style:dashed}
.matrix-cell svg{width:100%;height:auto;max-width:120px}
.option-grid.many{grid-template-columns:repeat(auto-fit,minmax(120px,1fr))}
.opt svg{width:100%;height:auto}
@media (max-width:560px){
 .matrix-board{grid-template-columns:repeat(3,minmax(74px,1fr));gap:6px;max-width:none}
 .matrix-cell{min-height:92px;padding:3px;border-radius:12px}
 .matrix-cell svg{max-width:94px}
 .option-grid.many{grid-template-columns:repeat(2,minmax(0,1fr))}
}


.textitem{display:inline-flex;align-items:center;justify-content:center;min-height:42px;padding:8px 10px;font-weight:800;color:#163b5a;text-align:center;line-height:1.5}
.set-board{display:grid;grid-template-columns:repeat(auto-fit,minmax(110px,1fr));gap:10px;max-width:650px;margin:12px auto 16px}
.set-cell,.analogy-cell{background:#fff;border:1.6px solid #d7e3ea;border-radius:14px;min-height:118px;display:flex;align-items:center;justify-content:center;position:relative;padding:8px}
.mini-label{position:absolute;top:6px;inset-inline-start:8px;background:#eef6fb;color:#24506f;border-radius:999px;padding:2px 8px;font-size:.8rem;font-weight:800}
.analogy-board{display:grid;grid-template-columns:1fr auto 1fr;gap:10px;align-items:center;max-width:680px;margin:12px auto 16px}
.analogy-arrow{display:flex;align-items:center;justify-content:center;color:#57758b;font-weight:800;padding:0 4px;text-align:center}
.analogy-board .missing{background:#f5fbff;border-style:dashed}
@media (max-width:560px){
 .set-board{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}
 .set-cell,.analogy-cell{min-height:96px;padding:4px}
 .analogy-board{grid-template-columns:1fr;max-width:320px}
 .analogy-arrow{font-size:.92rem}
}

/* v1.4.9 – true responsive visual canvas: same geometry across breakpoints */
@media (min-width:760px){
 .wrap{width:min(1120px,calc(100% - 36px))}
 .matrix-board{max-width:550px;gap:10px}
 .matrix-cell{min-height:155px}
 .matrix-cell svg{max-width:146px}
 .option-grid{grid-template-columns:repeat(4,minmax(0,1fr));max-width:960px;gap:12px}
 .option-grid.many{grid-template-columns:repeat(5,minmax(0,1fr))}
 .opt{min-height:160px}
 .opt svg{width:100%;height:auto;max-width:160px}
 .sequence{grid-template-columns:repeat(5,minmax(0,1fr));max-width:970px;gap:10px}
 .sequence-item{min-height:135px}
 .sequence-item svg{width:100%;height:auto;max-width:140px}
 .sequence.q-len-5 .sequence-item.missing{grid-column:auto;min-height:135px}
 .analogy-board{max-width:820px}
 .analogy-cell svg,.set-cell svg{max-width:142px;width:100%;height:auto}
}
.matrix-board{direction:ltr;max-width:550px;width:100%;grid-template-columns:repeat(3,minmax(0,1fr));}
.matrix-cell{aspect-ratio:1.07;min-height:0;overflow:hidden;padding:6px}
.matrix-cell svg{max-width:150px;width:100%;height:auto;max-height:150px;display:block}
.option-grid{direction:ltr}
.opt{min-width:0;min-height:142px;padding:12px 8px 7px}
.opt svg{height:auto;max-height:none;width:100%;max-width:150px;aspect-ratio:120/104}
.set-board{direction:ltr;grid-template-columns:repeat(5,minmax(0,1fr));max-width:950px}
.set-cell{min-width:0;aspect-ratio:1/1;min-height:0;padding:7px}
.set-cell svg,.analogy-cell svg{width:100%;height:auto;max-width:148px}
.analogy-board{direction:rtl;grid-template-columns:minmax(0,1fr) auto minmax(0,1fr) minmax(0,1fr) auto minmax(0,1fr);max-width:960px}
.analogy-cell{min-height:0;aspect-ratio:1.05;padding:7px;min-width:0}
.analogy-arrow{white-space:nowrap;font-size:13px}
.sequence{direction:rtl;grid-template-columns:repeat(5,minmax(0,1fr));max-width:950px}
.sequence-item{min-height:0;aspect-ratio:1.13;padding:6px}
.sequence-item svg{width:100%;height:auto;max-width:140px;aspect-ratio:120/104}
.sequence.q-len-5 .sequence-item.missing{grid-column:auto;min-height:0}
.code-examples{direction:rtl;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;max-width:800px;margin:14px auto}
.code-sample{direction:rtl}
.code-sample{border:1px solid #d4e5ee;border-radius:14px;padding:8px;display:flex;flex-direction:column;justify-content:center;align-items:center;gap:4px;background:#f9fcff}
.code-sample svg{width:100%;max-width:145px;height:auto}
.code-sample strong{font-size:19px;color:#103d57;direction:rtl}
.code-equals{color:#6b8190}
.code-target{display:flex;justify-content:center;align-items:center;flex-direction:column;max-width:210px;margin:12px auto;padding:12px;border:2px dashed #6cb3be;border-radius:15px;background:#f3fbfd}
.code-target svg{width:100%;max-width:160px;height:auto}
.target-title{font-weight:800;color:#196074}
@media (max-width:650px){
 .wrap{width:calc(100% - 12px)}
 .panel{padding:12px 8px}
 .matrix-board{gap:5px;max-width:100%;margin:12px auto}
 .matrix-cell{aspect-ratio:1.05;padding:2px;border-radius:9px}
 .matrix-cell svg{max-width:none;width:100%;height:auto}
 .sequence{grid-template-columns:repeat(3,minmax(0,1fr));gap:6px;max-width:100%}
 .sequence-item{aspect-ratio:1.07;padding:3px;border-radius:10px}
 .sequence-item svg{max-width:none;width:100%;height:auto}
 .sequence.q-len-5 .sequence-item.missing{grid-column:auto;min-height:0}
 .option-grid,.option-grid.many{grid-template-columns:repeat(2,minmax(0,1fr));gap:8px;max-width:100%}
 .opt{padding:11px 5px 5px;min-height:152px}
 .opt svg{width:100%;max-width:152px;height:auto}
 .set-board{grid-template-columns:repeat(3,minmax(0,1fr));gap:6px;max-width:100%}
 .set-cell{aspect-ratio:1/1;padding:3px;border-radius:9px}
 .set-cell svg{max-width:none;width:100%;height:auto}
 .analogy-board{grid-template-columns:repeat(2,minmax(0,1fr));gap:6px;max-width:100%}
 .analogy-arrow{display:none}
 .analogy-cell{aspect-ratio:1.15;max-width:none;padding:5px}
 .analogy-cell svg{max-width:145px}
 .code-examples{gap:6px}
 .code-sample{padding:4px;min-width:0}
 .code-sample strong{font-size:16px}
 .code-target{max-width:175px}
 .qa-title{font-size:17px;line-height:1.8}
}

/* v1.4.12: graduated alternating-pattern sequence layout, RTL preserved */
.sequence {direction:rtl;}
.sequence-item {overflow:hidden;}
.sequence-item svg {object-fit:contain;}
@media(min-width:760px){
  .sequence:has(> .sequence-item:nth-child(9)){grid-template-columns:repeat(5,minmax(0,1fr));max-width:970px}
  .sequence:has(> .sequence-item:nth-child(9)) .sequence-item{aspect-ratio:1.18;min-height:102px}
}
@media(max-width:650px){
  .sequence:has(> .sequence-item:nth-child(9)) {grid-template-columns:repeat(3,minmax(0,1fr));gap:5px}
  .sequence:has(> .sequence-item:nth-child(9)) .sequence-item{min-height:92px;aspect-ratio:1.02}
  .sequence:has(> .sequence-item:nth-child(9)) .sequence-item svg{max-width:none;width:100%;height:auto}
}


/* v1.4.13: clarity of question and after-submit review */
.answer-review{border:1px solid #cbdfe8;background:#f8fbfd;border-radius:11px;margin:8px 0;padding:9px 12px}
.answer-review summary{cursor:pointer;font-weight:800;color:#16425b}
.answer-review p{margin:6px 0;font-size:14px}
.opt.chosen:not(.correct):not(.wrong){border-color:#188c9c;background:#eafafa;box-shadow:inset 0 0 0 1px #188c9c}
.sequence .sequence-item .ord{display:block;font-weight:800;color:#5a7588;font-size:11px;font-family:Tahoma,Arial,sans-serif}
@media(max-width:650px){
 .sequence:has(> .sequence-item:nth-child(9)) .sequence-item{min-height:96px}
 .sequence:has(> .sequence-item:nth-child(9)) .sequence-item svg{max-height:84px}
 .matrix-cell svg,.opt svg{object-fit:contain}
}