/* ==========================================================================
   SRG ARCHIVE AJAX — Dynamic Loading States & Skeleton Placeholders
   Context-aware shimmer tints driven by --srg-context-accent-rgb.
   Strictly zero layout-shift: skeleton cards match real card dimensions.
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. SKELETON BASE — Shared shimmer utility
   -------------------------------------------------------------------------- */

/**
 * Core shimmer animation keyframes.
 * Uses a transparent → accent-tinted → transparent sweep to avoid cold-gray
 * generic placeholders. The tint is dynamically inherited from the section accent.
 */
@keyframes srg-shimmer {
    0%   { background-position: -600px 0; }
    100% { background-position:  600px 0; }
}

/* Base skeleton pulse for elements that do not need the full shimmer gradient */
@keyframes srg-skeleton-pulse {
    0%, 100% { opacity: 0.55; }
    50%       { opacity: 0.85; }
}

/* --------------------------------------------------------------------------
   2. SKELETON CARD — Software / Template / Generic Grid Card
   -------------------------------------------------------------------------- */

/**
 * .srg-skeleton-card
 * Matches .srg-software-card layout closely to prevent height jumps
 * when real cards replace skeletons on AJAX resolution.
 */
.srg-skeleton-card {
    background: var(--srg-bg-elevated, #fff);
    border: 1px solid var(--srg-border-primary, #e5e7eb);
    border-radius: var(--srg-radius-xl, 1rem);
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    min-height: 200px;
    overflow: hidden;

    /* Context-aware subtle border tint */
    border-color: rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.08);
}

/* Shimmer element shared helper */
.srg-skeleton-card__line {
    border-radius: var(--srg-radius-md, 0.5rem);
    background: linear-gradient(
        90deg,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.04) 25%,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.10) 50%,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.04) 75%
    );
    background-size: 600px 100%;
    animation: srg-shimmer 1.6s ease-in-out infinite;
}

/* Skeleton head row: logo placeholder + title block */
.srg-skeleton-card__head {
    display: flex;
    align-items: center;
    gap: 12px;
}

/* Logo / icon square placeholder */
.srg-skeleton-card__logo {
    width: 48px;
    height: 48px;
    flex-shrink: 0;
    border-radius: var(--srg-radius-lg, 0.75rem);
    background: linear-gradient(
        90deg,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.06) 25%,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.14) 50%,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.06) 75%
    );
    background-size: 600px 100%;
    animation: srg-shimmer 1.6s ease-in-out infinite;
}

/* Title + subtitle text lines in the head */
.srg-skeleton-card__title-block {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.srg-skeleton-card__title {
    height: 14px;
    width: 70%;
}

.srg-skeleton-card__subtitle {
    height: 10px;
    width: 45%;
}

/* Body description lines */
.srg-skeleton-card__body {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-top: 4px;
}

.srg-skeleton-card__desc-1 {
    height: 11px;
    width: 100%;
}

.srg-skeleton-card__desc-2 {
    height: 11px;
    width: 85%;
}

.srg-skeleton-card__desc-3 {
    height: 11px;
    width: 60%;
}

/* Footer CTA bar placeholder */
.srg-skeleton-card__footer {
    margin-top: auto;
    height: 32px;
    width: 35%;
    border-radius: var(--srg-radius-lg, 0.75rem);
    background: linear-gradient(
        90deg,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.05) 25%,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.12) 50%,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.05) 75%
    );
    background-size: 600px 100%;
    animation: srg-shimmer 1.6s ease-in-out infinite;
}

/* Stagger shimmer animation so adjacent skeleton cards feel alive, not robotic */
.srg-skeleton-card:nth-child(2) .srg-skeleton-card__line,
.srg-skeleton-card:nth-child(2) .srg-skeleton-card__logo,
.srg-skeleton-card:nth-child(2) .srg-skeleton-card__footer {
    animation-delay: 0.15s;
}

.srg-skeleton-card:nth-child(3) .srg-skeleton-card__line,
.srg-skeleton-card:nth-child(3) .srg-skeleton-card__logo,
.srg-skeleton-card:nth-child(3) .srg-skeleton-card__footer {
    animation-delay: 0.30s;
}

.srg-skeleton-card:nth-child(4) .srg-skeleton-card__line,
.srg-skeleton-card:nth-child(4) .srg-skeleton-card__logo,
.srg-skeleton-card:nth-child(4) .srg-skeleton-card__footer {
    animation-delay: 0.45s;
}

.srg-skeleton-card:nth-child(5) .srg-skeleton-card__line,
.srg-skeleton-card:nth-child(5) .srg-skeleton-card__logo,
.srg-skeleton-card:nth-child(5) .srg-skeleton-card__footer {
    animation-delay: 0.60s;
}

.srg-skeleton-card:nth-child(6) .srg-skeleton-card__line,
.srg-skeleton-card:nth-child(6) .srg-skeleton-card__logo,
.srg-skeleton-card:nth-child(6) .srg-skeleton-card__footer {
    animation-delay: 0.75s;
}

/* --------------------------------------------------------------------------
   3. GRID LOADING STATE — Opacity dim during Load More append cycles
   -------------------------------------------------------------------------- */

/**
 * Applied to the grid during a load-more fetch (NOT during filter swaps,
 * where skeletons fully replace the grid content instead).
 */
.srg-grid--loading {
    opacity: 0.4;
    pointer-events: none;
    transition: opacity 200ms ease;
}

/* Restore opacity as soon as the class is removed */
.srg-grid--loading-done {
    opacity: 1;
    transition: opacity 300ms ease;
}

/* --------------------------------------------------------------------------
   4. FILTER PILL LOADING STATE
   -------------------------------------------------------------------------- */

/**
 * Applied to a filter pill during an active AJAX filter fetch.
 * Shows a subtle pulse animation to communicate that a request is in-flight.
 */
.srg-filter-btn.is-loading,
.srg-dropdown-item.is-loading {
    opacity: 0.65;
    pointer-events: none;
    animation: srg-skeleton-pulse 1.2s ease-in-out infinite;
}

/* --------------------------------------------------------------------------
   5. LOAD MORE BUTTON — Spin keyframe (referenced from main.js inline CSS)
   -------------------------------------------------------------------------- */

/**
 * The .srg-loading-spinner element inside Load More buttons uses this keyframe.
 * Defined here centrally to avoid inline <style> injection.
 */
@keyframes spin {
    from { transform: rotate(0deg); }
    to   { transform: rotate(360deg); }
}

/* --------------------------------------------------------------------------
   6. "REACHED END" INDICATOR
   -------------------------------------------------------------------------- */

.srg-reached-end {
    text-align: center;
    margin-top: var(--srg-space-8, 2rem);
    padding: var(--srg-space-4, 1rem);
    color: var(--srg-text-tertiary);
    font-weight: var(--srg-weight-medium, 500);
    font-size: var(--srg-text-sm, 0.875rem);
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 400ms ease, transform 400ms ease;
}

.srg-reached-end.is-visible {
    opacity: 1;
    transform: translateY(0);
}

/* --------------------------------------------------------------------------
   7. DARK MODE ADJUSTMENTS
   -------------------------------------------------------------------------- */

html.srg-dark .srg-skeleton-card {
    background: var(--srg-neutral-800, #1e293b);
    border-color: rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.12);
}

html.srg-dark .srg-skeleton-card__line,
html.srg-dark .srg-skeleton-card__logo,
html.srg-dark .srg-skeleton-card__footer {
    background: linear-gradient(
        90deg,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.06) 25%,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.18) 50%,
        rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.06) 75%
    );
    background-size: 600px 100%;
}

/* --------------------------------------------------------------------------
   8. REDUCED MOTION — Accessibility compliance
   -------------------------------------------------------------------------- */

/**
 * Users who prefer reduced motion see a simple opacity pulse instead
 * of the full shimmer sweep. Prevents vestibular disorder discomfort.
 */
@media (prefers-reduced-motion: reduce) {
    .srg-skeleton-card__line,
    .srg-skeleton-card__logo,
    .srg-skeleton-card__footer {
        animation: srg-skeleton-pulse 2s ease-in-out infinite;
        background: rgba(var(--srg-context-accent-rgb, 124, 58, 237), 0.07);
        background-size: unset;
    }

    .srg-filter-btn.is-loading,
    .srg-dropdown-item.is-loading {
        animation: none;
        opacity: 0.6;
    }
}