/* Luogu-style tag filter panel for the problem list.
   Renders inside a Bootstrap modal (.modal-body). */

.tag-panel-inner {
    display: flex;
    flex-direction: column;
    gap: .5rem;
    max-height: 60vh;
    overflow-y: auto;
}

/* ---- A single group row: title + tag pills ---- */
.tag-group {
    display: flex;
    align-items: flex-start;
    gap: .85rem;
    padding: .4rem 0;
    border-bottom: 1px dashed rgba(148, 163, 184, 0.3);
}

.tag-group:last-of-type {
    border-bottom: none;
}

.tag-group-title {
    flex: 0 0 5.5rem;
    font-size: .82rem;
    font-weight: 600;
    color: #64748b;
    padding-top: .25rem;
}

.tag-group-items {
    display: flex;
    flex-wrap: wrap;
    gap: .4rem;
}

/* ---- Tag pill button ---- */
.tag-btn {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: .3rem;
    padding: .22rem .65rem;
    font-size: .82rem;
    line-height: 1.45;
    color: #1e293b;
    background: #fff;
    border: 1px solid #e2e8f0;
    border-radius: 6px;
    cursor: pointer;
    user-select: none;
    transition: background-color .12s ease, color .12s ease, border-color .12s ease;
}

/* Visually hidden but stays inside the pill's padding box, so when a click
   focuses it the browser only nudges the scrollable panel instead of
   jumping to a 1px element positioned elsewhere on the page. */
.tag-btn input {
    position: absolute;
    top: 0;
    left: 0;
    width: 1px;
    height: 1px;
    margin: 0;
    padding: 0;
    overflow: hidden;
    clip: rect(0 0 0 0);
    white-space: nowrap;
    border: 0;
}

.tag-btn:hover {
    background: #eff6ff;
    border-color: #bfdbfe;
    color: #2563eb;
}

.tag-btn:focus-within {
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

/* Active (checked) state */
.tag-btn.is-active {
    color: #fff;
    background: #3b82f6;
    border-color: #3b82f6;
}

.tag-btn.is-active .tag-btn-count {
    color: rgba(255, 255, 255, 0.88);
}

.tag-btn.is-active:hover {
    background: #2563eb;
    border-color: #2563eb;
    color: #fff;
}

/* Disabled (zero-count) state */
.tag-btn.is-disabled {
    color: #cbd5e1;
    background: #f8fafc;
    border-color: #f1f5f9;
    cursor: not-allowed;
}

.tag-btn.is-disabled:hover {
    background: #f8fafc;
    border-color: #f1f5f9;
    color: #cbd5e1;
}

.tag-btn-count {
    font-size: .72rem;
    color: #94a3b8;
    font-variant-numeric: tabular-nums;
}

/* ---- Panel footer status (inside modal-footer) ---- */
.tag-panel-status {
    font-size: .82rem;
}

/* ---- Selected tag chips ---- */
.tag-selected-row {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: .4rem;
}

.tag-selected-label {
    font-size: .82rem;
    color: #64748b;
}

.tag-selected-chip {
    display: inline-flex;
    align-items: center;
    gap: .35rem;
    padding: .2rem .65rem;
    font-size: .8rem;
    color: #fff;
    background: #3b82f6;
    border-radius: 999px;
    text-decoration: none;
    transition: background-color .12s ease;
}

.tag-selected-chip:hover {
    color: #fff;
    background: #2563eb;
}

.tag-selected-chip .bi {
    font-size: .68rem;
    opacity: .85;
}

@media (max-width: 575.98px) {
    .tag-group {
        flex-direction: column;
        gap: .3rem;
    }
    .tag-group-title {
        flex: none;
        padding-top: 0;
    }
}