/* ═══════════════════════════════════════════════════════════
   Accordion / collapsible — expandable sections
   A bordered stack of sections, each a header (chevron + title +
   optional right-aligned subtitle) that toggles a body open/closed.
   Toggle the `.is-open` class on the item (framework-agnostic — any
   app can flip it; a native <details>/<summary> works too).
   ═══════════════════════════════════════════════════════════ */

.tn-accordion {
    display: flex;
    flex-direction: column;
    gap: var(--tn-space-sm);
}

.tn-accordion-item {
    border: 1px solid var(--tn-border);
    border-radius: var(--tn-radius);
    overflow: hidden;
    background: var(--tn-bg-card);
}

.tn-accordion-header {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 10px 14px;
    background: var(--tn-bg-card);
    border: none;
    font-family: inherit;
    font-size: var(--tn-font-size-sm);
    font-weight: 600;
    color: var(--tn-text-primary);
    cursor: pointer;
    text-align: left;
    transition: background var(--tn-transition);
}

.tn-accordion-header:hover {
    background: var(--tn-bg-hover);
}

.tn-accordion-header:focus-visible {
    outline: none;
    box-shadow: inset 0 0 0 2px var(--tn-accent);
}

/* Chevron rotates from ▶ to ▼ when open (use bi-chevron-right) */
.tn-accordion-chevron {
    flex-shrink: 0;
    font-size: 0.8em;
    color: var(--tn-text-secondary);
    transition: transform var(--tn-transition);
}

.tn-accordion-item.is-open .tn-accordion-chevron {
    transform: rotate(90deg);
}

/* Optional right-aligned subtitle / meta on the header */
.tn-accordion-sub {
    margin-left: auto;
    font-weight: 400;
    color: var(--tn-text-muted);
    font-size: var(--tn-font-size-xs);
}

/* Body — hidden until the item is open */
.tn-accordion-body {
    display: none;
    padding: 14px;
    border-top: 1px solid var(--tn-border-light);
    background: var(--tn-bg-hover);
    font-size: var(--tn-font-size-sm);
    color: var(--tn-text-primary);
}

.tn-accordion-item.is-open .tn-accordion-body {
    display: block;
}

/* Native <details> fallback — same look without any JS:
   <details class="tn-accordion-item"><summary class="tn-accordion-header">…</summary>…</details> */
details.tn-accordion-item > .tn-accordion-header {
    list-style: none;
}

details.tn-accordion-item > .tn-accordion-header::-webkit-details-marker {
    display: none;
}

details.tn-accordion-item[open] .tn-accordion-chevron {
    transform: rotate(90deg);
}

details.tn-accordion-item[open] .tn-accordion-body {
    display: block;
}