@font-face{font-family:"Baloo";src:url(assets/baloo-arabic.woff2) format("woff2");font-weight:400 800;font-display:swap;unicode-range:U+0600-06FF,U+0750-077F,U+08A0-08FF,U+200C-200E,U+FB50-FDFF,U+FE70-FEFC}
@font-face{font-family:"Baloo";src:url(assets/baloo-latin.woff2) format("woff2");font-weight:400 800;font-display:swap;unicode-range:U+0000-00FF,U+2000-206F,U+2190-2193,U+2212}
:root{
  --bg1:#e9f3ff;--bg2:#fff6e5;--ink:#1f2a44;--muted:#55617f;--card:#fff;
  --blue:#4f7cff;--blue-d:#3358d4;--ok:#1fa463;--ok-bg:#e3f8ec;--bad:#e5484d;--bad-bg:#ffeceb;
  --orange:#ff9f1c;--green:#14a37f;--purple:#8a56f0;--r:22px;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;min-height:100vh;min-height:100dvh;display:flex;flex-direction:column;font-family:"Baloo","Segoe UI","Noto Sans Arabic",Tahoma,sans-serif;color:var(--ink);
  background:linear-gradient(170deg,var(--bg1),var(--bg2));font-size:19px;line-height:1.5}
main{width:100%;max-width:760px;margin:0 auto;padding:12px 12px 24px;flex:1}
[hidden]{display:none!important}
a{color:inherit}
.card{background:var(--card);border-radius:var(--r);box-shadow:0 8px 28px rgba(40,60,120,.12);padding:16px 14px 18px}
.center{text-align:center}
.btn{display:block;width:100%;font:inherit;font-weight:800;border:0;border-radius:18px;cursor:pointer;margin-top:12px;text-align:center;text-decoration:none;
  background:var(--blue);color:#fff;padding:12px 16px;min-height:56px;box-shadow:0 5px 0 var(--blue-d);transition:transform .08s}
.btn.big{font-size:1.35rem}
.btn:active{transform:translateY(3px);box-shadow:0 2px 0 var(--blue-d)}
.btn.ghost{background:#eef2fb;color:var(--blue-d);box-shadow:0 4px 0 #cdd6ec;font-size:1.1rem}
.btn.next{background:var(--ok);box-shadow:0 5px 0 #137a48}
:focus-visible{outline:4px solid #ffb703;outline-offset:2px}

/* app bar */
.appbar{position:sticky;top:0;z-index:5;display:flex;align-items:center;gap:8px;padding:8px 12px;padding-top:max(8px,env(safe-area-inset-top));
  background:rgba(255,255,255,.92);backdrop-filter:blur(8px);box-shadow:0 2px 12px rgba(40,60,120,.1)}
.appbar .back,.appbar .home-btn{flex:0 0 48px;height:48px;border-radius:14px;border:0;background:#eef2fb;font:inherit;font-size:1.5rem;font-weight:800;color:var(--blue-d);cursor:pointer;display:grid;place-items:center;text-decoration:none}
.bar-title{flex:1;margin:0;font-size:1.3rem;text-align:center;color:var(--blue-d);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}

/* home */
#v-home{position:relative;text-align:center;padding-top:6px}
.logo{display:block;width:100%;max-width:560px;height:auto;aspect-ratio:921/114;object-fit:contain;margin:0 auto 6px;border-radius:14px;background:#fff;padding:8px 12px;box-sizing:border-box;box-shadow:0 3px 12px rgba(40,60,120,.15)}
.stage{position:relative;width:100%;touch-action:none;user-select:none;-webkit-user-select:none}
.viewer-canvas{display:block;width:100%;height:100%;cursor:grab}
.viewer-canvas:active{cursor:grabbing}
.hero-stage{height:min(38vh,300px);margin:0 auto}
h1{font-size:2.3rem;line-height:1.15;margin:.1em 0 0;color:var(--blue-d)}
.sub{color:var(--muted);margin:.1em 0 .8em;font-size:1.1rem}
.menu{display:grid;gap:12px}
.tile{display:flex;align-items:center;gap:14px;text-align:right;text-decoration:none;border-radius:var(--r);padding:14px 16px;min-height:84px;color:#fff;
  box-shadow:0 6px 0 rgba(0,0,0,.15),0 10px 24px rgba(40,60,120,.15);transition:transform .08s}
.tile:active{transform:translateY(3px)}
.tile .ti{font-size:2.3rem;width:60px;height:60px;display:grid;place-items:center;background:rgba(255,255,255,.25);border-radius:18px;flex:0 0 auto}
.tile b{display:block;font-size:1.6rem;line-height:1.2}
.tile small{display:block;font-size:1rem;opacity:.95}
.t-learn{background:linear-gradient(135deg,#4f7cff,#6f9bff)}
.t-practice{background:linear-gradient(135deg,#14a37f,#2fc79a)}
.t-quiz{background:linear-gradient(135deg,#ff8a1c,#ffb13b)}
.credit{text-align:center;color:var(--muted);font-weight:700;font-size:1rem;padding:10px 12px calc(14px + env(safe-area-inset-bottom))}

/* learn */
.lead{font-weight:700;font-size:1.15rem;margin:4px 4px 10px;text-align:center}
.solid-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}
.solid-tile{background:#fff;border-radius:18px;padding:10px 8px 12px;text-align:center;text-decoration:none;box-shadow:0 4px 0 #dbe3f5,0 6px 18px rgba(40,60,120,.08);display:flex;flex-direction:column;align-items:center;min-height:150px;justify-content:center}
.solid-tile .th canvas{width:110px;height:110px;display:block}
.solid-tile b{font-size:1.15rem;line-height:1.25}
.solid-tile small{color:var(--muted);font-size:.9rem}
.solid-tile .emo{font-size:3rem}
.vol-tile{background:linear-gradient(135deg,#fff3dc,#fff)}
.solid-card{padding-top:8px}
.solid-stage{height:min(46vh,380px);border-radius:16px;background:radial-gradient(circle at 50% 40%,#f4f8ff,#e6eeff)}
.drag-hint{position:absolute;bottom:8px;right:0;left:0;text-align:center;font-size:.9rem;color:var(--muted);pointer-events:none;z-index:1}
.net-row{display:flex;gap:8px}
.net-btn{background:var(--orange);box-shadow:0 5px 0 #c9740a;font-size:1.25rem}
.solid-name{font-size:1.7rem;margin:12px 0 6px;text-align:center;color:var(--blue-d)}
.solid-name small{font-size:1.1rem;color:var(--muted)}
.facts{display:grid;grid-template-columns:repeat(4,1fr);gap:8px}
.fact{background:#f2f5ff;border-radius:16px;padding:8px 4px;text-align:center;border:3px solid transparent;transition:all .2s}
.fact b{display:block;font-size:2rem;line-height:1.1;color:var(--blue-d)}
.fact span{font-size:.92rem;font-weight:700;color:var(--muted);line-height:1.2;display:block}
.fact.glow{border-color:#ff2f6d;background:#ffe8ef;transform:scale(1.05)}
.f-bases b{color:#d27a00}.f-curved b{color:var(--green)}
.show-row{display:flex;flex-wrap:wrap;align-items:center;gap:8px;margin-top:12px;justify-content:center}
.show-label{font-weight:800;white-space:nowrap}
.pill{font:inherit;font-weight:800;font-size:1.05rem;border:3px solid #cdd8f0;background:#fff;color:var(--ink);border-radius:999px;padding:4px 13px;min-height:48px;cursor:pointer}
@media (min-width:381px){.show-row{flex-wrap:nowrap}}
.pill.on{background:#ff2f6d;border-color:#ff2f6d;color:#fff}
.info{list-style:none;padding:0;margin:14px 0 0;display:grid;gap:8px}
.info li{background:#f8faff;border-radius:14px;padding:8px 12px;font-size:1.05rem}
.life{margin-top:12px;display:flex;flex-wrap:wrap;gap:6px;align-items:center}
.life-chip{background:#fff3dc;border-radius:999px;padding:3px 12px;font-weight:700;font-size:1rem}
.pager{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.sliders{display:grid;gap:6px;margin-top:10px}
.sliders label{display:grid;grid-template-columns:90px 34px 1fr;align-items:center;gap:8px;font-weight:800}
.sliders output{font-size:1.4rem;color:var(--blue-d);text-align:center}
input[type=range]{width:100%;height:44px;accent-color:var(--blue)}
.formula{background:#f2f5ff;border-radius:16px;padding:8px 14px;margin-top:10px}
.formula p{margin:4px 0}
.eq{display:inline-block;unicode-bidi:isolate;font-weight:800;white-space:nowrap}

/* practice */
.practice-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}
.p-tile{background:#fff;border-radius:18px;padding:14px 10px;min-height:120px;text-align:center;text-decoration:none;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:4px;box-shadow:0 4px 0 #dbe3f5,0 6px 18px rgba(40,60,120,.08)}
.p-tile .ti{font-size:2.4rem}
.p-tile b{font-size:1.12rem;line-height:1.25}

/* exercise */
.ex-top{display:flex;align-items:center;justify-content:space-between;gap:8px;margin:0 2px 10px;min-height:32px}
.dots{display:flex;gap:6px;list-style:none;padding:0;margin:0;flex-wrap:wrap}
.dots li{width:16px;height:16px;border-radius:50%;background:#d5ddef}
.dots li.cur{background:var(--blue);transform:scale(1.25)}
.dots li.ok{background:var(--ok)}.dots li.bad{background:var(--bad)}
.score-pill{font-weight:800;background:#fff;border-radius:999px;padding:2px 14px;box-shadow:0 2px 8px rgba(0,0,0,.08);margin-inline-start:auto;white-space:nowrap}
.ex-num{margin:0;color:var(--muted);font-weight:700;text-align:center;font-size:1rem}
.prompt{font-size:1.45rem;font-weight:800;text-align:center;margin:4px 0 8px;line-height:1.35}
.visual{display:flex;justify-content:center;align-items:center;margin-bottom:6px}
.ex-stage{height:min(36vh,280px);border-radius:16px;background:radial-gradient(circle at 50% 40%,#f4f8ff,#e6eeff)}
.net-svg{width:100%;max-width:340px;max-height:300px;height:auto}
.net-svg.grid{max-width:300px;max-height:240px}
.box-svg{width:100%;max-width:360px;height:auto;max-height:260px}
.box-svg .lbl{font:800 17px "Baloo",Tahoma,sans-serif;fill:#1f2a44;text-anchor:middle;direction:rtl;unicode-bidi:plaintext}
.emo{font-family:"Apple Color Emoji","Segoe UI Emoji","Noto Color Emoji",sans-serif}
.emo.huge{font-size:6.5rem;line-height:1.2;filter:drop-shadow(0 6px 10px rgba(0,0,0,.15))}
.emo.big{font-size:5rem}
.v-emoji{min-height:150px}
.choices{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:6px}
.choices.two .choice{font-size:1.5rem}
.choices.nets{grid-template-columns:repeat(3,1fr)}
.choice{font:inherit;font-weight:800;font-size:1.2rem;line-height:1.25;border:3px solid #cdd8f0;background:#fff;color:var(--ink);border-radius:18px;min-height:64px;padding:8px 6px;cursor:pointer;
  box-shadow:0 4px 0 #cdd8f0;transition:transform .08s}
.choice:active{transform:translateY(2px)}
.choices.nets .choice{padding:6px;display:grid;place-items:center}
.choice .net-svg.small{max-height:130px;width:100%}
.choice.right{border-color:var(--ok);background:var(--ok-bg);box-shadow:0 4px 0 #9ad9b5}
.choice.wrong{border-color:var(--bad);background:var(--bad-bg);box-shadow:0 4px 0 #f1a9ab}
.choice:disabled{cursor:default;color:var(--ink)}
.choice:disabled:not(.right):not(.wrong){opacity:.6}
.feedback{margin-top:12px;border-radius:16px;padding:10px 14px}
.feedback b{font-size:1.25rem}
.feedback p{margin:4px 0 0}
.feedback.ok{background:var(--ok-bg);color:#0d5a34}
.feedback.bad{background:#fff4e0;color:#7a4300}
.trophy{font-size:4.5rem;line-height:1.1}
.score{font-size:3rem;font-weight:800;margin:0;color:var(--blue-d)}
.end-stars{font-size:2.2rem;letter-spacing:4px}
.end-msg{font-size:1.35rem;font-weight:800;margin:6px 0}
.summary{list-style:none;padding:0;margin:10px 0 0;text-align:right;display:grid;gap:6px}
.summary li{border-radius:12px;padding:6px 10px;display:flex;gap:6px;font-size:1rem}
.summary li.ok{background:var(--ok-bg)}.summary li.bad{background:var(--bad-bg)}
#confetti{position:fixed;inset:0;pointer-events:none;z-index:50;width:100%;height:100%}
.nojs{text-align:center;padding:20px}

/* bigger screens: tablet / classroom screen */
@media (min-width:700px){
  body{font-size:21px}
  .solid-grid{grid-template-columns:repeat(3,1fr)}
  .practice-grid{grid-template-columns:repeat(3,1fr)}
  .menu{grid-template-columns:repeat(3,1fr)}
  .tile{flex-direction:column;text-align:center;min-height:170px;justify-content:center}
  .logo{max-width:620px}
  .hero-stage{height:min(40vh,340px)}
  .ex-stage{height:min(40vh,340px)}
}
@media (max-width:380px){
  .facts{grid-template-columns:repeat(2,1fr)}
  .choice{font-size:1.08rem}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important}}