:root{
  --bg:#000;--card:#0B0F18;--card2:#111827;--line:#1E2A44;--blue:#1F5BFF;--bright:#4A86FF;
  --white:#fff;--muted:#9AA4B8;--ok:#22C55E;--warn:#F5B53D;--danger:#EF4444;--gray:#6B7488;
  --r:18px;--safe-t:env(safe-area-inset-top,0px);--safe-b:env(safe-area-inset-bottom,0px);
  color-scheme:dark;
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;background:var(--bg);color:var(--white);font:16px/1.45 Barlow,system-ui,-apple-system,"Segoe UI",sans-serif}
body{min-height:100vh;background:radial-gradient(120% 60% at 100% 0%,rgba(31,91,255,.22),transparent 60%),var(--bg)}
#app{max-width:560px;margin:0 auto;padding:calc(16px + var(--safe-t)) 18px calc(28px + var(--safe-b))}
.boot{display:grid;place-items:center;min-height:70vh}.boot img{width:96px;opacity:.9;animation:pulse 1.4s ease-in-out infinite}
@keyframes pulse{50%{opacity:.4}}
h1,h2,h3,.disp{font-family:"Barlow Condensed",Barlow,sans-serif;font-style:italic;font-weight:800;letter-spacing:.5px;margin:0;line-height:1.05;text-transform:uppercase}
h1{font-size:38px}h2{font-size:26px}h3{font-size:20px}
.top{display:flex;align-items:center;justify-content:space-between;margin-bottom:18px;gap:10px}
.brand{display:flex;align-items:center;gap:10px}.brand img{width:40px;height:40px;border-radius:10px}
.brand b{font-family:"Barlow Condensed",sans-serif;font-style:italic;font-weight:800;font-size:22px;letter-spacing:1px}
.brand small{display:block;color:var(--bright);font-size:11px;letter-spacing:3px;font-weight:700;margin-top:-2px}
.card{background:linear-gradient(180deg,var(--card2),var(--card));border:1px solid var(--line);border-radius:var(--r);padding:18px;margin:14px 0}
.hero{background:linear-gradient(135deg,#0A36C9,var(--blue));border:0;box-shadow:0 12px 40px rgba(31,91,255,.35)}
.cap{color:var(--muted);font-size:12px;font-weight:800;letter-spacing:2px;text-transform:uppercase}
.hero .cap{color:rgba(255,255,255,.8)}
.big{font-family:"Barlow Condensed",sans-serif;font-style:italic;font-weight:800;font-size:34px;line-height:1}
.muted{color:var(--muted)}.small{font-size:14px}.center{text-align:center}
.row{display:flex;gap:10px;align-items:center}.row.wrap{flex-wrap:wrap}.grow{flex:1}
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:12px}
label{display:block;font-size:13px;font-weight:700;color:var(--muted);letter-spacing:.5px;margin:12px 0 6px}
input,select,textarea{width:100%;font:inherit;font-size:17px;color:var(--white);background:#05070C;border:1px solid var(--line);border-radius:14px;padding:14px 14px;outline:none;appearance:none;-webkit-appearance:none}
select{background-image:linear-gradient(45deg,transparent 50%,var(--bright) 50%),linear-gradient(135deg,var(--bright) 50%,transparent 50%);background-position:calc(100% - 22px) 50%,calc(100% - 16px) 50%;background-size:6px 6px;background-repeat:no-repeat;padding-right:40px}
input:focus,select:focus,textarea:focus{border-color:var(--bright);box-shadow:0 0 0 3px rgba(74,134,255,.25)}
textarea{min-height:90px;resize:vertical}
.btn{display:flex;align-items:center;justify-content:center;gap:8px;width:100%;min-height:54px;border:0;border-radius:16px;font:800 17px Barlow,sans-serif;letter-spacing:.5px;color:#fff;background:var(--blue);margin-top:14px;cursor:pointer;text-decoration:none;text-transform:uppercase;box-shadow:0 8px 24px rgba(31,91,255,.35)}
.btn:active{transform:scale(.98)}.btn[disabled]{opacity:.5;pointer-events:none}
.btn.ghost{background:transparent;border:1.5px solid var(--line);box-shadow:none;color:var(--white)}
.btn.danger{background:transparent;border:1.5px solid var(--danger);color:var(--danger);box-shadow:none}
.btn.ok{background:var(--ok);box-shadow:none;color:#04130A}
.btn.sm{min-height:44px;font-size:14px;margin-top:0;width:auto;padding:0 16px}
.link{background:none;border:0;color:var(--bright);font:700 15px Barlow,sans-serif;padding:10px 0;cursor:pointer;text-decoration:underline}
.badge{display:inline-block;padding:5px 12px;border-radius:999px;font-weight:800;font-size:12px;letter-spacing:1.5px;text-transform:uppercase;border:1.5px solid currentColor}
.b-activo{color:var(--ok)}.b-pendiente{color:var(--warn)}.b-vencido{color:var(--danger)}.b-suspendido{color:#FF7A7A}.b-archivado,.b-sin{color:var(--gray)}
.list{display:flex;flex-direction:column;gap:10px;margin-top:12px}
.item{display:block;width:100%;text-align:left;background:var(--card);border:1px solid var(--line);border-radius:16px;padding:14px 16px;color:inherit;font:inherit;cursor:pointer}
.item:active{border-color:var(--bright)}
.item .n{font-weight:800;font-size:17px}.item .e{color:var(--muted);font-size:14px;word-break:break-all}
.kv{display:grid;grid-template-columns:auto 1fr;gap:6px 14px;font-size:15px}.kv dt{color:var(--muted)}.kv dd{margin:0;font-weight:700;text-align:right;word-break:break-word}
.actions{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:12px}.actions .btn{margin-top:0}
.pay{border-top:1px solid var(--line);padding:12px 0}.pay:first-child{border-top:0}
.notice{border-left:4px solid var(--warn);background:rgba(245,181,61,.08);padding:12px 14px;border-radius:12px;font-size:14px;color:#F3E2BC}
.err{color:#FF8A8A;font-weight:700;font-size:14px;margin-top:10px}
.chips{display:flex;gap:8px;overflow-x:auto;padding-bottom:4px;margin-top:10px}
.chip{flex:none;border:1.5px solid var(--line);background:transparent;color:var(--white);border-radius:999px;padding:9px 14px;font:700 14px Barlow,sans-serif;cursor:pointer}
.chip.on{border-color:var(--bright);background:rgba(31,91,255,.2)}
.back{background:none;border:0;color:var(--white);font:800 15px Barlow,sans-serif;padding:8px 0;cursor:pointer;display:flex;gap:6px;align-items:center}
.sheet{position:fixed;inset:0;background:rgba(0,0,0,.7);display:flex;align-items:flex-end;justify-content:center;z-index:20}
.sheet>div{width:100%;max-width:560px;max-height:92vh;overflow:auto;background:#05070C;border:1px solid var(--line);border-bottom:0;border-radius:24px 24px 0 0;padding:20px 18px calc(24px + var(--safe-b))}
.linkbox{word-break:break-all;font-size:13px;background:#05070C;border:1px dashed var(--bright);border-radius:12px;padding:12px;color:#CFE0FF}
#toast{position:fixed;left:50%;bottom:calc(24px + var(--safe-b));transform:translateX(-50%) translateY(120%);background:#fff;color:#000;font-weight:800;padding:12px 18px;border-radius:14px;transition:transform .25s;z-index:40;max-width:90vw;text-align:center}
#toast.on{transform:translateX(-50%) translateY(0)}
.foot{margin-top:28px;text-align:center;color:var(--gray);font-size:12px;letter-spacing:2px;text-transform:uppercase}
.lock{font-size:46px;text-align:center;margin:6px 0}
/* v2.0.0 · pestañas del alumno y sin desborde lateral */
html,body{overflow-x:hidden;max-width:100%}
#app,.card,.top{min-width:0}.top .brand{min-width:0}.brand small{white-space:nowrap}
.tabs{display:grid;grid-template-columns:repeat(5,1fr);gap:6px;margin:14px 0 4px}
.tab{background:var(--card);border:1px solid var(--line);border-radius:14px;color:#C9D1E0;font:800 11px Barlow,sans-serif;text-transform:uppercase;padding:10px 2px;display:flex;flex-direction:column;align-items:center;gap:4px;cursor:pointer}
.tab span{font-size:22px}.tab.on{border-color:var(--bright);background:rgba(31,91,255,.22);color:#fff}
details summary{cursor:pointer;list-style:none}details summary::-webkit-details-marker{display:none}
input[type=checkbox]{-webkit-appearance:checkbox;appearance:auto;width:26px;height:26px;padding:0;accent-color:#22C55E}


/* v2.3.0 · GIF de cada ejercicio, completo y grande */
.gifbox{display:none}
.gifbox.on{display:block;margin:2px 0 12px;border-radius:16px;overflow:hidden;background:#05070C;border:1px solid var(--line);text-align:center}
.gifbox.on>img{display:block;margin:0 auto;max-width:100%;max-height:340px;width:auto;height:auto}
.gifbox .flip{position:relative;width:100%;aspect-ratio:4/3}
.gifbox .flip img{position:absolute;inset:0;width:100%;height:100%;object-fit:contain;background:#fff}
.gifbox .flip img.b{animation:rpFlip 1.6s steps(1,end) infinite}
@keyframes rpFlip{0%{opacity:0}50%{opacity:1}100%{opacity:0}}
/* v3.0.0 · términos, registro y progreso */
.legalbox{max-height:42vh;overflow:auto;border:1px solid var(--line);border-radius:14px;padding:4px 14px;margin:10px 0;background:#05070C}
.legal h3{font-size:16px;margin:14px 0 6px}.legal p{margin:6px 0;color:#C9D1E0;line-height:1.45}
.chk{display:flex;gap:10px;align-items:flex-start;font-size:14px;margin:10px 0;color:#E6EAF2;text-transform:none;letter-spacing:0}
.chk input{flex:0 0 auto;margin-top:1px}
input.mini{width:70px;padding:8px 10px;margin:0;font-size:16px}