:root{--ink:#173647;--teal:#087e83;--paper:#f3f6f5}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:18px/1.85 Tahoma,Arial,sans-serif}header{background:#123d4b;color:white;padding:38px max(5%,calc((100% - 1100px)/2))}header p{color:#d1ece7}h1{font-size:34px;line-height:1.4}h2{font-size:25px}h3{font-size:21px}main{max-width:1100px;margin:auto;padding:24px}nav{display:flex;flex-wrap:wrap;gap:8px;padding:18px 0}button,nav a,select{font:inherit;border:1px solid #b7cfcd;border-radius:10px;padding:9px 16px;background:white;color:var(--ink);cursor:pointer}nav a{text-decoration:none}button:hover,nav a:hover{background:#e3f1ef}section{background:white;border:1px solid #dbe5e3;border-radius:18px;margin:20px 0;padding:28px;scroll-margin-top:20px}.badge{background:#deefb8;color:#24412b;border-radius:30px;padding:5px 14px;display:inline-block;font-size:14px}.note{background:#edf6f4;border-right:4px solid var(--teal);padding:16px}.en,[lang=en]{direction:ltr;unicode-bidi:isolate;display:inline-block}table{border-collapse:collapse;width:100%;font-size:15px}th,td{padding:12px;border-bottom:1px solid #dbe5e3;text-align:right}th{background:#eaf3f1}.scroll{overflow-x:auto}.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:14px}.card,.quiz{border:1px solid #dbe5e3;border-radius:12px;padding:18px;margin:12px 0}.quiz p{margin:8px 0}.feedback{color:#075b54;font-weight:bold}progress{width:100%;accent-color:var(--teal)}details{margin:14px 0}summary{cursor:pointer;color:#086c73;font-weight:bold}img{max-width:100%;height:auto}textarea{width:100%;min-height:110px;font:inherit;border:1px solid #aac4c2;padding:12px;border-radius:8px}.small{font-size:14px;color:#557077}footer{text-align:center;padding:30px}label{display:block}button.primary{background:var(--teal);color:white}a{color:#087e83}@media(max-width:600px){main{padding:12px}section{padding:18px}h1{font-size:27px}header{padding:25px}button,select{max-width:100%}}@media print{body{background:white;font-size:12pt}header{background:white;color:#123d4b;padding:0}header p{color:#123d4b}nav,button,select,progress,.screen{display:none}section{border:0;padding:6px;break-inside:auto}h2,h3{break-after:avoid}details>*{display:block}table{font-size:9pt}main{padding:0}.quiz{break-inside:avoid}}

/* Subject palette: teal learning, violet practice, amber hints, green success. */
body{background:#f1f5fa}header{background:linear-gradient(120deg,#17455d,#087e83)}
section{border-top:5px solid #17858a;box-shadow:0 5px 22px #17364708}
#map{border-top-color:#5476bc}#start,#test{border-top-color:#8561b1}#explain,#vocab{border-top-color:#16877c}#book{border-top-color:#4275b9}#listen{border-top-color:#368caa}#next{border-top-color:#ce9130}
h2{color:#126d72}#start h2,#test h2{color:#68438e}#book h2,#map h2{color:#365f9a}#next h2{color:#8b5c13}
nav a{background:#e9f4f3;border-color:#b7dcd7;color:#185e61;font-weight:bold}nav a[href="#start"],nav a[href="#test"]{background:#f1eafb;border-color:#d9c7ed;color:#68438e}nav a[href="#next"]{background:#fff3d9;border-color:#ebcf93;color:#805516}
.note{background:#edf7f4;border-color:#16877c;color:#225a51}#book .note,#next .note{background:#fff5df;border-color:#c78a21;color:#795117}
.quiz{background:#f7f3fc;border-color:#dfd0ed;border-right:5px solid #8b68b0}.quiz>p:first-child{color:#493465;font-weight:bold}.quiz select{background:#fff;border-color:#bfacd6}
.quiz button{margin:4px;background:#f0e8fa;color:#604283;border-color:#d5c2e9}.quiz button:nth-of-type(1){background:#fff1cf;color:#785213;border-color:#e5cb8d}.quiz button:nth-of-type(2){background:#dcf2e8;color:#175f44;border-color:#a9d8c2}.quiz button:nth-of-type(3){background:#e4efff;color:#28588e;border-color:#b7d0ef}
.feedback:empty{display:none}.feedback:not(:empty){background:#edf3fb;color:#30557c;border-radius:10px;padding:12px;border-right:4px solid #6d93c0}.feedback[data-tone="success"]{background:#dff3e7;color:#185b36;border-color:#32915c}.feedback[data-tone="retry"]{background:#fff0dd;color:#825015;border-color:#ce9130}.feedback[data-tone="hint"]{background:#fff7d9;color:#765614;border-color:#d4a438}
.card{background:#f0f8f6;border-color:#c5e1d9}.card:nth-child(3n+2){background:#f1f5fc;border-color:#cad9ef}.card:nth-child(3n){background:#fbf4e9;border-color:#ecdbc0}summary{background:#ecf5f4;padding:10px 14px;border-radius:9px}#book details>summary{background:#edf3fc;color:#365f9a}
button:focus-visible,a:focus-visible,select:focus-visible,input:focus-visible,summary:focus-visible{outline:3px solid #9161bb;outline-offset:3px}button:hover{filter:brightness(.96)}
@media print{section{box-shadow:none;border-top:2px solid #8ea9a8}.quiz,.card,.note{background:white}.feedback:not(:empty){background:white}}

.platform-layout{max-width:1450px;margin:auto;display:grid;grid-template-columns:275px minmax(0,1fr);gap:22px;padding:22px}.platform-layout main{width:100%;min-width:0;padding:0}.platform-sidebar{align-self:start;position:sticky;top:18px;background:white;border:1px solid #cbdedb;border-radius:18px;padding:18px}.platform-sidebar h2{font-size:21px;margin:0 0 12px}.platform-sidebar details{margin:0}.platform-sidebar summary{background:#164f5b;color:white}.channel-list{display:grid;gap:8px;margin-top:12px}.channel-list button{text-align:right;width:100%;font-size:16px;background:#f0f6f8;border-color:#d3e2e6}.channel-list button[aria-current="page"]{background:#087e83;color:white;border-color:#087e83;font-weight:bold}.channel-list button small{display:block;font-size:11px;opacity:.9}.platform-sidebar .small{line-height:1.8}.channel-heading{background:#e4efee;border-radius:14px;padding:15px 20px;font-size:22px;font-weight:bold;margin-bottom:16px}.platform-layout main>nav{display:none}main>section[hidden]{display:none!important}.platform-layout main>section{margin-top:0}.unit-status{font-size:13px;background:#fff4db;padding:12px;border-radius:9px;color:#7a571c}.channel-footer{display:flex;gap:12px;margin:20px 0}.channel-footer button{flex:1}.platform-intro{font-size:15px}header h1{font-size:30px}header{padding:26px max(4%,calc((100% - 1400px)/2))}
@media(max-width:760px){.platform-layout{grid-template-columns:1fr;padding:12px;gap:12px}.platform-sidebar{position:static}.channel-list{grid-template-columns:repeat(2,minmax(0,1fr))}.channel-list button{font-size:14px;padding:10px}.platform-sidebar h2{font-size:18px}.channel-heading{font-size:19px}.platform-layout main{padding:0}}
@media print{.platform-layout{display:block;padding:0}.platform-sidebar,.channel-heading,.channel-footer{display:none}.platform-layout main>section[hidden]{display:block!important}}
/* Horizontal unit navigation */
.platform-layout{display:flex;flex-direction:column;gap:18px}.platform-sidebar{position:static;align-self:stretch;width:100%;padding:16px 20px}.platform-sidebar h2{display:inline-block;margin:0 0 12px;font-size:19px}.platform-sidebar details>summary{display:inline-block;min-width:230px;list-style:none;cursor:pointer}.platform-sidebar details>summary::after{content:" ▾";margin-right:18px}.platform-sidebar details[open]>summary::after{content:" ▴"}.channel-list{display:flex;flex-direction:row;flex-wrap:wrap;gap:8px}.channel-list button{width:auto;flex:0 1 auto;min-width:140px;text-align:center}.platform-sidebar .unit-status{margin:12px 0 0}.platform-sidebar>p.small{margin:8px 0 0}.platform-layout main{max-width:none}.platform-sidebar details>p.small{margin:8px 0}.platform-sidebar summary:focus-visible{outline:3px solid #9161bb;outline-offset:3px}
@media(max-width:760px){.platform-sidebar{padding:14px}.platform-sidebar details>summary{width:100%;min-width:0}.channel-list{display:flex;flex-wrap:nowrap;overflow-x:auto;padding:4px 2px 12px;scroll-snap-type:x proximity}.channel-list button{flex:0 0 155px;min-width:0;scroll-snap-align:start}.platform-sidebar details>p.small::after{content:" — اسحب الأقسام أفقيًا لرؤية المزيد."}}
@media print{.platform-sidebar{display:none}.platform-layout{display:block}}