:root{--bg:#fbfaf7;--bg2:#f3f1ea;--card:#fff;--ink:#16201d;--ink2:#4b5753;--line:#e3e0d6;--brand:#0B5D4B;--brand2:#0e7a62;--gold:#b38a3c;--gold2:#D9B26A;--ok:#11795f;--shadow:0 1px 2px rgba(0,0,0,.04),0 6px 24px rgba(0,0,0,.05);--r:16px;
--ui:'IBM Plex Sans Arabic',system-ui,-apple-system,'Segoe UI',Tahoma,sans-serif;--read:'Noto Naskh Arabic','IBM Plex Sans Arabic',serif}
@media (prefers-color-scheme:dark){:root:not([data-theme=light]){--bg:#0d1412;--bg2:#121c19;--card:#16211e;--ink:#e7eeeb;--ink2:#a9b7b2;--line:#25332f;--brand:#5fd0ae;--brand2:#7fe0c2;--gold:#D9B26A;--ok:#5fd0ae;--shadow:none}}
:root[data-theme=dark]{--bg:#0d1412;--bg2:#121c19;--card:#16211e;--ink:#e7eeeb;--ink2:#a9b7b2;--line:#25332f;--brand:#5fd0ae;--brand2:#7fe0c2;--gold:#D9B26A;--ok:#5fd0ae;--shadow:none}
*{box-sizing:border-box}html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:72px}
body{margin:0;background:var(--bg);color:var(--ink);font:400 16px/1.7 var(--ui);-webkit-font-smoothing:antialiased}
a{color:var(--brand);text-decoration:none}a:hover{text-decoration:underline}
.wrap{max-width:1100px;margin:0 auto;padding:0 18px}
.skip{position:absolute;inset-inline-start:-999px}.skip:focus{inset-inline-start:8px;top:8px;background:var(--card);padding:8px;z-index:99}
:focus-visible{outline:3px solid var(--gold2);outline-offset:2px;border-radius:6px}
.top{position:sticky;top:0;z-index:20;background:color-mix(in srgb,var(--bg) 88%,transparent);backdrop-filter:saturate(1.4) blur(12px);-webkit-backdrop-filter:saturate(1.4) blur(12px);border-bottom:1px solid var(--line)}
.top-in{display:flex;align-items:center;gap:12px;height:60px}
.brand{display:flex;align-items:center;gap:8px;color:var(--ink);font-weight:700;white-space:nowrap}.brand:hover{text-decoration:none}
.logo{width:30px;height:30px;flex:none}
.hsearch{position:relative;flex:1;max-width:420px;margin-inline-start:auto}
input[type=search],.ask input{width:100%;font:inherit;color:var(--ink);background:var(--card);border:1px solid var(--line);border-radius:999px;padding:9px 16px;outline:none;transition:border-color .15s}
input[type=search]:focus,.ask input:focus{border-color:var(--brand)}
.icon-btn{border:1px solid var(--line);background:var(--card);color:var(--ink);width:40px;height:40px;border-radius:50%;font-size:18px;cursor:pointer;flex:none}
.i-sun{display:none}[data-theme=dark] .i-sun{display:inline}[data-theme=dark] .i-moon{display:none}
@media (prefers-color-scheme:dark){:root:not([data-theme=light]) .i-sun{display:inline}:root:not([data-theme=light]) .i-moon{display:none}}
@media (max-width:640px){.brand span{display:none}.hsearch{max-width:none}}
.sugg{position:absolute;inset-inline:0;top:calc(100% + 6px);background:var(--card);border:1px solid var(--line);border-radius:14px;box-shadow:0 12px 40px rgba(0,0,0,.12);overflow:hidden;z-index:30;text-align:start}
.sugg a{display:block;padding:10px 14px;color:var(--ink);border-bottom:1px solid var(--line)}.sugg a:last-child{border:0}.sugg a:hover,.sugg a.on{background:var(--bg2);text-decoration:none}
.sugg small{display:block;color:var(--ink2);font-size:13px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.hero{padding:48px 0 28px;text-align:center;background:radial-gradient(1200px 400px at 50% -120px,color-mix(in srgb,var(--brand) 14%,transparent),transparent)}
.hero h1{font-size:clamp(34px,7vw,58px);line-height:1.15;margin:0 0 10px;letter-spacing:-.5px}.hero h1 span{color:var(--brand)}
.lead{font-size:clamp(16px,2.4vw,19px);color:var(--ink2);max-width:640px;margin:0 auto 22px}
.bigsearch{position:relative;display:flex;gap:8px;max-width:640px;margin:0 auto 18px}
.bigsearch input{padding:14px 20px;font-size:17px;box-shadow:var(--shadow)}
.bigsearch button,.ask button,.btn{font:600 16px var(--ui);border:0;border-radius:999px;background:var(--brand);color:#fff;padding:0 22px;cursor:pointer;min-height:46px}
[data-theme=dark] .bigsearch button,[data-theme=dark] .ask button,[data-theme=dark] .btn{color:#06201a}
@media (prefers-color-scheme:dark){:root:not([data-theme=light]) .bigsearch button,:root:not([data-theme=light]) .ask button,:root:not([data-theme=light]) .btn{color:#06201a}}
.btn.ghost{background:transparent;color:var(--brand);border:1px solid var(--line);display:inline-flex;align-items:center}
.cats{display:flex;flex-wrap:wrap;gap:8px;justify-content:center}
.chip{display:inline-block;font:600 13px/1 var(--ui);padding:6px 11px;border-radius:999px;background:var(--bg2);color:var(--ink2);border:1px solid var(--line)}
.chip.big{font-size:15px;padding:10px 16px;color:var(--ink)}.chip small{color:var(--ink2);font-weight:400}a.chip:hover{text-decoration:none;border-color:var(--brand)}
.c-science{color:#1565a8}.c-math{color:#7b3fb0}.c-history{color:#9a5b12}.c-saudi{color:#0B6B4B}.c-tech{color:#b0365b}.c-economy{color:#3d6b10}
[data-theme=dark] .chip{filter:brightness(1.6)}
@media (prefers-color-scheme:dark){:root:not([data-theme=light]) .chip{filter:brightness(1.6)}}
.group{margin:34px 0}.ghead{display:flex;align-items:baseline;justify-content:space-between}.ghead h2{margin:0 0 12px;font-size:22px}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:14px}
.card{display:block;background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:16px 18px;color:var(--ink);box-shadow:var(--shadow);transition:transform .15s,border-color .15s}
.card:hover{text-decoration:none;transform:translateY(-2px);border-color:var(--brand)}
.card h3{margin:10px 0 4px;font-size:19px}.card p{margin:0;color:var(--ink2);font-size:14.5px;line-height:1.6}
.ask{margin:26px 0;background:var(--card);border:1px solid var(--line);border-radius:22px;padding:22px;box-shadow:var(--shadow)}
.ask h2{margin:0 0 4px}.ask form{display:flex;gap:8px;margin-top:12px}.ask input{border-radius:14px;padding:12px 16px}
.muted{color:var(--ink2)}
#askout{margin-top:14px}.vbadge{display:inline-block;font:600 13px var(--ui);padding:1px 10px;border-radius:999px;background:#e3f2ea;color:#0b5d4b;text-decoration:none;margin-inline-end:6px}.vbadge.part{background:#fdf0d5;color:#8a5a00}[data-theme=dark] .vbadge{background:#12352b;color:#9fe0c3}[data-theme=dark] .vbadge.part{background:#3a2c0c;color:#f3c86b}.ans{font-family:var(--read);font-size:18px;line-height:1.9;background:var(--bg2);border-radius:14px;padding:14px 16px}
.ans .sref{font:600 12px var(--ui);vertical-align:super;color:var(--brand)}
.psg{border-inline-start:3px solid var(--gold2);padding:6px 12px;margin:10px 0}.psg b a{color:var(--ink)}.psg p{margin:4px 0;font-family:var(--read)}.psg .srcs{font-size:13px}
.today{margin:20px 0}.kicker{display:block;font:700 13px var(--ui);color:var(--gold);letter-spacing:.5px;margin-bottom:6px}
.why{margin:40px 0;background:linear-gradient(135deg,var(--brand),#083f33);color:#fff;border-radius:22px;padding:24px}
.why h2{margin-top:0}.why ul{margin:0;padding-inline-start:20px;columns:2 260px}.why li{margin:4px 0;break-inside:avoid}
.foot{border-top:1px solid var(--line);margin-top:40px;padding:22px 0;color:var(--ink2);font-size:14px}.foot .links a{margin:0 2px}
.crumbs{font-size:14px;color:var(--ink2);margin:18px 0 4px}
.ptitle{font-size:32px;margin:12px 0 4px}
.art .ahead h1{font-size:clamp(30px,6vw,46px);line-height:1.2;margin:10px 0 0}
.en{margin:2px 0 6px;color:var(--ink2);font-size:15px;text-align:end}
.meta{color:var(--ink2);font-size:14px;margin:0 0 16px}.ok{color:var(--ok);font-weight:600}
.tldr{background:var(--card);border:1px solid var(--line);border-radius:20px;padding:16px 18px 6px;box-shadow:var(--shadow);margin-bottom:22px}
.seg{display:inline-flex;background:var(--bg2);border-radius:999px;padding:4px;margin-bottom:6px;flex-wrap:wrap}
.seg button{font:600 14.5px var(--ui);border:0;background:transparent;color:var(--ink2);padding:8px 14px;border-radius:999px;cursor:pointer;min-height:38px}
.seg button[aria-selected=true]{background:var(--card);color:var(--brand);box-shadow:0 1px 4px rgba(0,0,0,.12)}
.tldr p{font-family:var(--read);font-size:19px;line-height:1.95;margin:8px 0 12px}.tldr .note{font:13px var(--ui);color:var(--ink2)}
.cols{display:grid;grid-template-columns:1fr;gap:22px}
@media (min-width:900px){.cols{grid-template-columns:300px 1fr}.side{position:sticky;top:76px;align-self:start}}
.facts{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:14px 16px;margin-bottom:14px}
.facts h2,.toc summary{font-size:16px;margin:0 0 8px;font-weight:700}
.fact{display:flex;justify-content:space-between;gap:12px;padding:8px 0;border-top:1px solid var(--line)}.fact:first-child{border-top:0}
.fact dt{color:var(--ink2);font-size:14px;flex:none;max-width:45%}.fact dd{margin:0;font-weight:600;font-size:14.5px;text-align:end}
.toc{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:12px 16px}.toc summary{cursor:pointer}.toc ol{margin:6px 0 0;padding-inline-start:20px;font-size:15px}
.content h2{font-size:24px;margin:26px 0 6px;line-height:1.35}.content section:first-child h2{margin-top:0}
.content p{font-family:var(--read);font-size:18.5px;line-height:2;margin:0 0 14px}
sup.cite{font:600 11px/1 var(--ui);vertical-align:super;margin-inline-start:2px}sup.cite a{display:inline-block;min-width:17px;padding:2px 4px;line-height:1.25;border-radius:6px;background:color-mix(in srgb,var(--brand) 12%,transparent);text-align:center}
sup.cite a:hover{text-decoration:none;background:var(--brand);color:#fff}
.quiz{background:var(--card);border:1px solid var(--line);border-radius:20px;padding:16px 18px;margin-top:26px}
.q{border:0;padding:0;margin:0 0 16px}.q legend{font-weight:700;margin-bottom:8px}
.q button{display:block;width:100%;text-align:start;font:16px var(--ui);color:var(--ink);background:var(--bg2);border:1px solid var(--line);border-radius:12px;padding:11px 14px;margin:6px 0;cursor:pointer;min-height:46px}
.q button:hover:not(:disabled){border-color:var(--brand)}.q button:disabled{cursor:default}
.q button.right{background:color-mix(in srgb,#16a34a 18%,var(--card));border-color:#16a34a}.q button.wrong{background:color-mix(in srgb,#dc2626 15%,var(--card));border-color:#dc2626}
.q .qwhy{font-size:14.5px;color:var(--ink2);margin:6px 2px 0}.score{font-weight:700;color:var(--brand)}
.refs a bdi,.psg bdi{unicode-bidi:isolate}.refs ol{padding-inline-start:22px}.refs li{margin:8px 0;line-height:1.6;scroll-margin-top:80px}.refs li:target{background:color-mix(in srgb,var(--gold2) 25%,transparent);border-radius:8px}
.refs .pub{color:var(--ink2);font-size:14px}.refs .host{display:block;color:var(--ink2);font-size:12.5px}
.actions{display:flex;gap:10px;flex-wrap:wrap;margin:22px 0}
.related{margin:34px 0}
.results{list-style:none;padding:0}.results li{background:var(--card);border:1px solid var(--line);border-radius:14px;padding:12px 16px;margin:10px 0}.results p{margin:6px 0 0;color:var(--ink2);font-size:15px}
.prose{max-width:760px}.prose p,.prose li{font-size:17.5px}
.pop{position:fixed;z-index:50;max-width:min(360px,92vw);background:var(--card);color:var(--ink);border:1px solid var(--line);border-radius:14px;box-shadow:0 14px 44px rgba(0,0,0,.2);padding:12px 14px;font-size:14.5px;line-height:1.55}
.pop b{display:block}.pop .p{color:var(--ink2);font-size:13px}.pop a{display:inline-block;margin-top:6px;font-weight:600}
@media (max-width:640px){.pop{inset-inline:4vw!important;bottom:14px!important;top:auto!important;max-width:none}}
@media (prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}
@media print{.top,.foot,.seg,.quiz,.actions,.related,.ask{display:none}.v-simple{display:none!important}.v-sum{display:block!important}}