/* ============================================================
   FLASHCARDS DE ESTUDIO — Maestro Hansell
   Estilo "carta coleccionable" para repasar materias de carrera.
   ============================================================ */

.franja-mazos {
    padding: 0 24px 30px;
    max-width: 1180px;
    margin: 0 auto;
}

.mazos-scroll {
    display: flex;
    gap: 14px;
    overflow-x: auto;
    padding-bottom: 10px;
    scrollbar-width: thin;
}

.mazo-boton {
    flex: 0 0 auto;
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--bg-card);
    border: 1px solid var(--linea);
    color: var(--tinta-tenue);
    border-radius: 30px;
    padding: 10px 18px;
    cursor: pointer;
    font-family: var(--f-texto);
    font-size: 0.88rem;
    font-weight: 600;
    transition: border-color .2s ease, color .2s ease, background .2s ease;
    white-space: nowrap;
}

.mazo-boton .icono-mazo { font-size: 1.05rem; }

.mazo-boton .cuenta {
    font-family: var(--f-mono);
    font-size: 0.72rem;
    color: var(--tinta-débil);
    background: rgba(255,255,255,0.06);
    border-radius: 20px;
    padding: 2px 8px;
}

.mazo-boton:hover { color: var(--tinta); border-color: var(--color-mazo, var(--acento)); }

.mazo-boton.activo {
    background: var(--color-mazo, var(--acento));
    border-color: var(--color-mazo, var(--acento));
    color: #0a0d12;
}
.mazo-boton.activo .cuenta { background: rgba(0,0,0,0.18); color: #0a0d12; }

/* ---------- ARENA DE ESTUDIO ---------- */
.arena-estudio {
    max-width: 1180px;
    margin: 0 auto;
    padding: 10px 24px 100px;
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    gap: 26px;
}

.barra-progreso-wrap {
    display: flex;
    align-items: center;
    gap: 14px;
    font-family: var(--f-mono);
    font-size: 0.78rem;
    color: var(--tinta-débil);
}

.barra-progreso {
    flex: 1;
    height: 4px;
    background: var(--linea);
    border-radius: 4px;
    overflow: hidden;
}

.barra-progreso .relleno {
    height: 100%;
    width: 0%;
    background: var(--color-mazo, var(--acento));
    transition: width .3s ease;
}

/* ---------- LA CARTA ---------- */
.escenario-carta {
    display: flex;
    justify-content: center;
    perspective: 1600px;
}

.carta {
    width: 100%;
    max-width: 420px;
    aspect-ratio: 5 / 7;
    position: relative;
    cursor: pointer;
    transform-style: preserve-3d;
    transition: transform .55s cubic-bezier(.2,.8,.2,1);
}

.carta.volteada { transform: rotateY(180deg); }

.carta .cara {
    position: absolute;
    inset: 0;
    backface-visibility: hidden;
    border-radius: 20px;
    padding: 22px;
    display: flex;
    flex-direction: column;
    background:
        linear-gradient(155deg, var(--bg-card) 0%, var(--bg-elevada) 100%);
    border: 1px solid var(--linea);
    box-shadow: 0 20px 50px -20px rgba(0,0,0,0.6);
    overflow: hidden;
}

.carta .cara::before {
    /* Marco tipo "holo" en el borde, color según el mazo */
    content: '';
    position: absolute;
    inset: 0;
    padding: 2px;
    border-radius: 20px;
    background: linear-gradient(135deg, var(--color-mazo, var(--acento)), transparent 40%, transparent 60%, var(--color-mazo, var(--acento)));
    -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
    opacity: 0.9;
    pointer-events: none;
}

.carta .cara-trasera { transform: rotateY(180deg); }

.carta-encabezado {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 14px;
}

.carta-tema {
    font-family: var(--f-mono);
    font-size: 0.68rem;
    letter-spacing: .06em;
    text-transform: uppercase;
    color: var(--color-mazo, var(--acento));
}

.carta-nivel {
    font-family: var(--f-mono);
    font-size: 0.65rem;
    padding: 3px 9px;
    border-radius: 20px;
    border: 1px solid var(--color-mazo, var(--acento));
    color: var(--color-mazo, var(--acento));
    white-space: nowrap;
}

.carta-cuerpo {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 10px 6px;
}

.carta-cuerpo p {
    font-family: var(--f-display);
    font-size: 1.15rem;
    font-weight: 600;
    line-height: 1.4;
}

.cara-trasera .carta-cuerpo p {
    font-family: var(--f-texto);
    font-weight: 400;
    font-size: 1rem;
    text-align: left;
}

.carta-pie {
    text-align: center;
    font-family: var(--f-mono);
    font-size: 0.68rem;
    color: var(--tinta-débil);
    letter-spacing: .05em;
}

.carta .cara::after {
    /* numerito estilo carta, esquina inferior */
    content: attr(data-num);
    position: absolute;
    bottom: 14px;
    right: 18px;
    font-family: var(--f-mono);
    font-size: 0.65rem;
    color: var(--tinta-débil);
}

/* ---------- CONTROLES ---------- */
.controles-carta {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 14px;
    flex-wrap: wrap;
}

.controles-carta button {
    font-family: var(--f-texto);
    font-weight: 600;
    font-size: 0.88rem;
    border-radius: 30px;
    padding: 11px 20px;
    cursor: pointer;
    border: 1px solid var(--linea);
    background: var(--bg-card);
    color: var(--tinta);
    transition: border-color .2s ease, color .2s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.controles-carta button:hover { border-color: var(--color-mazo, var(--acento)); color: var(--color-mazo, var(--acento)); }

.controles-carta .primario {
    background: var(--color-mazo, var(--acento));
    border-color: var(--color-mazo, var(--acento));
    color: #0a0d12;
}
.controles-carta .primario:hover { color: #0a0d12; filter: brightness(1.08); }

.controles-carta .aprendida { background: rgba(47,208,138,0.12); border-color: var(--c-escritor); color: var(--c-escritor); }

/* ---------- FORMULARIO: AGREGAR CARTA ---------- */
.panel-nueva-carta {
    max-width: 620px;
    margin: 10px auto 0;
    background: var(--bg-card);
    border: 1px solid var(--linea);
    border-radius: var(--radio);
    padding: 24px;
}

.panel-nueva-carta summary {
    cursor: pointer;
    font-weight: 600;
    font-size: 0.92rem;
    list-style: none;
    display: flex;
    align-items: center;
    gap: 8px;
}
.panel-nueva-carta summary::-webkit-details-marker { display: none; }
.panel-nueva-carta summary::before { content: '＋'; color: var(--acento); font-size: 1.1rem; }
.panel-nueva-carta[open] summary::before { content: '－'; }

.form-carta { margin-top: 18px; display: grid; gap: 12px; }

.form-carta label {
    font-size: 0.8rem;
    color: var(--tinta-tenue);
    display: block;
    margin-bottom: 6px;
}

.form-carta input, .form-carta select, .form-carta textarea {
    width: 100%;
    background: var(--bg-elevada);
    border: 1px solid var(--linea);
    border-radius: var(--radio-chico);
    padding: 10px 12px;
    color: var(--tinta);
    font-family: var(--f-texto);
    font-size: 0.9rem;
}

.form-carta textarea { resize: vertical; min-height: 70px; }

.form-carta .fila-doble {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.form-carta .btn-guardar {
    justify-self: start;
    margin-top: 4px;
}

.aviso-vacio {
    text-align: center;
    color: var(--tinta-débil);
    padding: 60px 20px;
    font-size: 0.95rem;
}

@media (max-width: 640px) {
    .form-carta .fila-doble { grid-template-columns: 1fr; }
    .carta { max-width: 340px; }
}