:root{--azul:#1e3a8a;--azul-oscuro:#172554;--verde:#0f766e;--verde-oscuro:#115e59;--gris-fondo:#e2e8f0;--tinta:#0f172a;--tinta-suave:#475569;--borde:#cbd5e1;--rojo:#b91c1c}*{box-sizing:border-box}html,body{background:var(--gris-fondo);color:var(--tinta);margin:0;padding:0;font-family:Segoe UI,Roboto,Arial,sans-serif;line-height:1.6}img{max-width:100%;display:block}video{background:#000;border-radius:12px;max-width:100%}h1{color:var(--azul);margin:0 0 12px;font-size:clamp(26px,4vw,34px)}h2{color:var(--azul);margin:24px 0 10px;font-size:clamp(20px,3vw,26px)}h3{color:var(--tinta);margin:18px 0 8px;font-size:20px}p{font-size:17px}.texto-suave{color:var(--tinta-suave)}.pantalla-centro{justify-content:center;align-items:center;min-height:100vh;padding:16px;display:flex}.contenedor{max-width:960px;margin:0 auto;padding:24px 16px 64px}.tarjeta{background:#fff;border-radius:18px;padding:clamp(20px,4vw,36px);box-shadow:0 10px 30px #00000026}.btn{cursor:pointer;text-align:center;border:none;border-radius:12px;padding:14px 20px;font-size:17px;font-weight:700;transition:transform 50ms,filter .1s;display:inline-block}.btn:active{transform:translateY(2px)}.btn:disabled{opacity:.6;cursor:default}.btn-primario{background:var(--azul);color:#fff;box-shadow:0 4px 0 var(--azul-oscuro)}.btn-verde{background:var(--verde);color:#fff;box-shadow:0 4px 0 var(--verde-oscuro)}.btn-secundario{color:var(--azul);border:2px solid var(--azul);background:#fff}.btn-bloque{width:100%}.campo{border:1px solid var(--borde);border-radius:12px;width:100%;margin-bottom:14px;padding:15px;font-size:17px}.mensaje{min-height:22px;color:var(--rojo);margin:12px 0 0;font-weight:600}.mensaje.ok{color:#166534}.mensaje.info{color:var(--azul)}.login-caja{text-align:center;width:100%;max-width:640px}.login-portada{border-radius:14px;margin-bottom:22px}.bloque-seccion{border-radius:12px;margin:6px 0 14px;padding:10px 14px;font-size:17px;font-weight:800}.bloque-seccion.azul{color:var(--azul);background:#eff6ff}.bloque-seccion.verde{color:var(--verde);background:#ecfdf5}.rejilla-registro{grid-template-columns:1fr;gap:12px;margin-bottom:16px;display:grid}.cabecera-home{background:var(--azul);color:#fff;border-radius:18px;margin-bottom:22px;padding:clamp(20px,4vw,32px)}.cabecera-home h1{color:#fff}.cabecera-home p{color:#dbeafe;margin:4px 0 0}.bienvenida{border-left:6px solid var(--verde);background:#ecfdf5;border-radius:12px;margin-bottom:20px;padding:16px 18px;font-size:17px}.rejilla-clases{grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:18px;display:grid}.clase-card{background:#fff;border-radius:16px;flex-direction:column;display:flex;overflow:hidden;box-shadow:0 8px 22px #0000001f}.clase-card img{object-fit:cover;width:100%;height:160px}.clase-card .cuerpo{flex-direction:column;flex:1;gap:10px;padding:16px;display:flex}.clase-card h3{color:var(--azul);margin:0}.clase-card .desc{color:var(--tinta-suave);flex:1;font-size:15px}.pill{color:var(--tinta-suave);background:#f1f5f9;border-radius:999px;align-self:flex-start;padding:4px 10px;font-size:13px;font-weight:700}.pill.ok{color:#166534;background:#dcfce7}.pill.pendiente{color:#854d0e;background:#fef9c3}.barra-superior{flex-wrap:wrap;justify-content:flex-end;gap:10px;margin-bottom:16px;display:flex}.contenido-clase p{margin:14px 0}.contenido-clase img{border-radius:14px;margin:18px 0}.recuadro-azul{border:1px solid #bfdbfe;border-left:6px solid var(--azul);background:#eff6ff;border-radius:12px;margin:20px 0;padding:18px 22px}.recuadro-azul>:first-child{margin-top:0}.recuadro-azul>:last-child{margin-bottom:0}.recuadro-azul h2,.recuadro-azul h3{color:var(--azul)}.nota-editor{color:#92400e;background:#fffbeb;border:1px dashed #f59e0b;border-radius:12px;margin:18px 0;padding:14px 16px;font-size:15px}.pregunta{border:1px solid var(--borde);background:#f8fafc;border-radius:12px;margin-bottom:16px;padding:16px 18px}.pregunta legend{color:var(--azul);padding:0 6px;font-weight:700}.pregunta .enunciado{margin:4px 0 12px;font-size:17px;font-weight:700}.opcion{cursor:pointer;background:#fff;border:1px solid #e2e8f0;border-radius:10px;align-items:flex-start;gap:10px;margin-bottom:8px;padding:10px 12px;display:flex}.opcion input{margin-top:4px}.resultado{border-left:6px solid var(--verde);background:#ecfdf5;border-radius:12px;margin-top:18px;padding:18px}.resultado.malo{background:#fef2f2;border-left-color:#dc2626}.resultado h2{margin:0 0 6px}.acciones-fila{flex-wrap:wrap;gap:12px;margin-top:22px;display:flex}.estudiante-bloque{border:1px solid var(--borde);background:#fff;border-radius:12px;margin-bottom:14px;padding:16px}.nota-fila{border:1px solid var(--borde);border-left:6px solid var(--verde);background:#ecfdf5;border-radius:10px;margin-top:10px;padding:12px 14px}.nota-fila.pendiente{background:#fef2f2;border-left-color:#dc2626}@media (width>=620px){.rejilla-registro{grid-template-columns:1fr 1fr}}