/* ============================================================
   NeuroLab — atlas.css
   Árbol de temas numerado y desplegable (panel lateral del atlas)
   ============================================================ */

/* --- Cabecera del panel --- */
.nl-tree-head {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    gap: .5rem;
    margin-bottom: .85rem;
}
.nl-tree-head h3 {
    font-size: .85rem;
    margin: 0;
    color: var(--gray-300);
}
.nl-tree-toggle-all {
    border: 0;
    background: none;
    padding: 0;
    font-family: inherit;
    font-size: .68rem;
    font-weight: 700;
    letter-spacing: .02em;
    color: var(--gray-500);
    cursor: pointer;
    transition: color var(--t-fast);
    white-space: nowrap;
}
.nl-tree-toggle-all:hover { color: var(--violet-light); }

/* --- Nodo del árbol --- */
/* El nodo es una fila: enlace al tema + botón que despliega los subtemas. */
#topic-tree .nl-tree-node {
    display: flex;
    align-items: flex-start;
    gap: .15rem;
    border-radius: 9px;
    font-size: .85rem;
    color: var(--gray-300);
    transition: background var(--t-fast), color var(--t-fast);
}
#topic-tree .nl-tree-node:hover { background: rgba(139,92,246,.1); color: var(--white); }

/* Enlace: abre tema.php */
#topic-tree .nl-tree-node__link {
    flex: 1;
    min-width: 0;
    display: flex;
    align-items: flex-start;
    gap: .5rem;
    padding: .45rem .3rem .45rem .55rem;
    border-radius: 9px;
    color: inherit;
    text-decoration: none;
}
#topic-tree .nl-tree-node__link:hover { color: var(--white); }
#topic-tree .nl-tree-node__link:focus-visible {
    outline: 2px solid var(--violet);
    outline-offset: 1px;
}

/* Botón: despliega / repliega los subtemas */
#topic-tree .nl-tree-node__toggle {
    flex-shrink: 0;
    display: flex;
    align-items: center;
    gap: .3rem;
    padding: .45rem .5rem;
    border: 0;
    background: none;
    border-radius: 9px;
    color: inherit;
    font-family: inherit;
    cursor: pointer;
    transition: background var(--t-fast);
}
#topic-tree .nl-tree-node__toggle:hover { background: rgba(139,92,246,.16); }
#topic-tree .nl-tree-node__toggle:focus-visible {
    outline: 2px solid var(--violet);
    outline-offset: 1px;
}

/* Tema principal: más peso visual que un subtema */
#topic-tree .nl-tree-node.is-root {
    font-weight: 700;
    color: var(--gray-100);
    margin-top: .15rem;
}
#topic-tree .nl-tree-node.is-child { font-size: .8rem; font-weight: 600; }

#topic-tree .nl-tree-node.active {
    background: rgba(139,92,246,.16);
    color: var(--violet-light);
    font-weight: 700;
}

/* Numeración */
.nl-tree-node__num {
    flex-shrink: 0;
    padding-top: .08rem;
    min-width: 2.1rem;
    font-size: .72rem;
    font-weight: 800;
    color: var(--violet);
    letter-spacing: .04em;   /* los romanos respiran mejor con algo de tracking */
    text-align: right;       /* alinea los íconos en columna, como un índice impreso */
}
.nl-tree-node.is-child .nl-tree-node__num {
    min-width: 2.4rem;
    font-size: .68rem;
    font-variant-numeric: tabular-nums;
    letter-spacing: .01em;
    color: var(--gray-500);
    font-weight: 700;
}
.nl-tree-node.active .nl-tree-node__num { color: var(--violet-light); }

.nl-tree-node__ico { flex-shrink: 0; font-size: .95rem; line-height: 1; }
.nl-tree-node__txt {
    flex: 1;
    line-height: 1.3;
    min-width: 0;
    overflow-wrap: anywhere;   /* el nombre completo se ve, aunque el panel sea angosto */
}

/* Contador de subtemas */
.nl-tree-node__count {
    flex-shrink: 0;
    min-width: 1.15rem;
    padding: .05rem .3rem;
    border-radius: 100px;
    background: rgba(139,92,246,.15);
    color: var(--violet-light);
    font-size: .62rem;
    font-weight: 800;
    text-align: center;
    line-height: 1.5;
}
.nl-tree-node.is-open .nl-tree-node__count {
    background: rgba(139,92,246,.07);
    color: var(--gray-500);
}

/* Chevron que gira al desplegar */
.nl-tree-node__chev {
    flex-shrink: 0;
    width: 0; height: 0;
    border-left: 5px solid currentColor;
    border-top: 4px solid transparent;
    border-bottom: 4px solid transparent;
    color: var(--gray-500);
    transition: transform var(--t-fast), color var(--t-fast);
}
.nl-tree-node__toggle:hover .nl-tree-node__chev { color: var(--violet-light); }
.nl-tree-node.is-open .nl-tree-node__chev { transform: rotate(90deg); }

/* --- Rama de subtemas --- */
#topic-tree .nl-tree-children {
    margin: .15rem 0 .35rem .95rem;
    padding-left: .55rem;
    border-left: 1.5px solid var(--gray-700);
    animation: nlTreeIn var(--t-fast) ease both;
}
#topic-tree .nl-tree-children[hidden] { display: none; }

@keyframes nlTreeIn {
    from { opacity: 0; transform: translateY(-3px); }
    to   { opacity: 1; transform: none; }
}

@media (prefers-reduced-motion: reduce) {
    #topic-tree .nl-tree-node,
    #topic-tree .nl-tree-node__toggle,
    .nl-tree-node__chev,
    #topic-tree .nl-tree-children { transition: none; animation: none; }
}

/* ============================================================
   Tarjeta de actividad — compartida por atlas.php y tema.php
   (antes vivía en el <style> inline de atlas.php)
   ============================================================ */
.nl-act-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 1rem;
}
.nl-act-card {
    display: block;
    background: var(--navy-mid);
    border: 1px solid var(--gray-700);
    border-radius: var(--radius);
    padding: 1.25rem;
    text-decoration: none;
    transition: border-color var(--t-base), transform var(--t-base);
}
.nl-act-card:hover {
    border-color: rgba(139,92,246,.35);
    transform: translateY(-3px);
}
.nl-act-card__tipo {
    display: inline-block;
    padding: .2rem .65rem;
    border-radius: 100px;
    font-size: .7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .04em;
    margin-bottom: .65rem;
}
.nl-act-card__tipo.lamina     { background: rgba(139,92,246,.15); color: var(--violet-light); }
.nl-act-card__tipo.simulador  { background: rgba(236,72,153,.18); color: #F472B6; }
.nl-act-card__tipo.comparador { background: rgba(109,40,217,.18); color: var(--violet-light); }
.nl-act-card__tipo.labeling   { background: rgba(139,92,246,.15); color: var(--violet-light); }
.nl-act-card__tipo.quiz       { background: rgba(236,72,153,.18); color: #F472B6; }
.nl-act-card__title { font-size: 1rem; font-weight: 700; color: var(--white); margin-bottom: .35rem; }
.nl-act-card__desc  { font-size: .82rem; color: var(--gray-500); line-height: 1.5; }

/* Tema de origen, cuando la actividad viene de un subtema */
.nl-act-card__origen {
    display: block;
    margin-top: .6rem;
    font-size: .7rem;
    font-weight: 700;
    color: var(--gray-500);
}

@media (prefers-reduced-motion: reduce) {
    .nl-act-card { transition: none; }
    .nl-act-card:hover { transform: none; }
}