/* ============================================================
   Skeleton Loading System
   ============================================================
   Shimmer + pulse animations for skeleton placeholders.
   Supports light/dark themes via data-theme attribute.
   Uses standardized breakpoints from breakpoints.css.
   ============================================================ */

/* ---------- Theme Variables ---------- */

/* Light theme skeleton colors */
[data-theme="light"] {
    --skeleton-base: #e2e8f0;
    --skeleton-highlight: #f1f5f9;
    --skeleton-text: #cbd5e1;
    --skeleton-card: #f8fafc;
    --skeleton-border: #e2e8f0;
    --skeleton-shimmer-start: rgba(226, 232, 240, 0.6);
    --skeleton-shimmer-mid: rgba(241, 245, 249, 0.9);
    --skeleton-shimmer-end: rgba(226, 232, 240, 0.6);
}

/* Dark theme skeleton colors */
[data-theme="dark"] {
    --skeleton-base: #1e293b;
    --skeleton-highlight: #334155;
    --skeleton-text: #475569;
    --skeleton-card: #1e293b;
    --skeleton-border: #334155;
    --skeleton-shimmer-start: rgba(30, 41, 59, 0.6);
    --skeleton-shimmer-mid: rgba(51, 65, 85, 0.9);
    --skeleton-shimmer-end: rgba(30, 41, 59, 0.6);
}

/* ---------- Base Skeleton ---------- */

.skeleton {
    position: relative;
    overflow: hidden;
    background: var(--skeleton-base);
    border-radius: 0.5rem;
    pointer-events: none;
    user-select: none;
}

.skeleton::after {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(
        90deg,
        var(--skeleton-shimmer-start) 0%,
        var(--skeleton-shimmer-mid) 50%,
        var(--skeleton-shimmer-end) 100%
    );
    transform: translateX(-100%);
    animation: skeleton-shimmer 1.8s ease-in-out infinite;
}

@keyframes skeleton-shimmer {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(100%);
    }
}

/* Pulse animation variant */
.skeleton--pulse {
    animation: skeleton-pulse 2s ease-in-out infinite;
}

.skeleton--pulse::after {
    display: none;
}

@keyframes skeleton-pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

/* Solid (no animation) variant */
.skeleton--solid::after {
    display: none;
}

/* ---------- Skeleton Text ---------- */

.skeleton-text {
    display: block;
    height: 1rem;
    margin-bottom: 0.5rem;
    border-radius: 0.25rem;
}

.skeleton-text:last-child {
    margin-bottom: 0;
}

/* Text size variants */
.skeleton-text--xs {
    height: 0.75rem;
    width: 60%;
}

.skeleton-text--sm {
    height: 0.875rem;
    width: 80%;
}

.skeleton-text--md {
    height: 1rem;
    width: 100%;
}

.skeleton-text--lg {
    height: 1.25rem;
    width: 90%;
}

.skeleton-text--xl {
    height: 1.75rem;
    width: 75%;
}

.skeleton-text--2xl {
    height: 2.25rem;
    width: 65%;
}

/* ---------- Skeleton Circle ---------- */

.skeleton-circle {
    border-radius: 50%;
    width: 2.5rem;
    height: 2.5rem;
    flex-shrink: 0;
}

.skeleton-circle--sm {
    width: 1.5rem;
    height: 1.5rem;
}

.skeleton-circle--md {
    width: 2.5rem;
    height: 2.5rem;
}

.skeleton-circle--lg {
    width: 3.5rem;
    height: 3.5rem;
}

.skeleton-circle--xl {
    width: 5rem;
    height: 5rem;
}

/* ---------- Skeleton Card ---------- */

.skeleton-card {
    padding: 1.25rem;
    border: 1px solid var(--skeleton-border);
    background: var(--skeleton-card);
}

.skeleton-card__header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.skeleton-card__body {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.skeleton-card__footer {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--skeleton-border);
}

/* ---------- Skeleton Image ---------- */

.skeleton-image {
    width: 100%;
    height: 12rem;
    border-radius: 0.5rem;
    background: var(--skeleton-base);
}

.skeleton-image--sm {
    height: 8rem;
}

.skeleton-image--md {
    height: 12rem;
}

.skeleton-image--lg {
    height: 18rem;
}

.skeleton-image--xl {
    height: 24rem;
}

.skeleton-image--square {
    aspect-ratio: 1 / 1;
    height: auto;
}

.skeleton-image--wide {
    aspect-ratio: 16 / 9;
    height: auto;
}

/* ---------- Skeleton List ---------- */

.skeleton-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.skeleton-list__item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 0.75rem;
    border-radius: 0.5rem;
    background: var(--skeleton-card);
    border: 1px solid var(--skeleton-border);
}

/* ---------- Skeleton Hero ---------- */

.skeleton-hero {
    padding: 2rem 1.5rem;
    border-radius: 0.75rem;
    background: var(--skeleton-card);
    border: 1px solid var(--skeleton-border);
}

.skeleton-hero__eyebrow {
    width: 30%;
    margin-bottom: 0.75rem;
}

.skeleton-hero__title {
    height: 2.5rem;
    margin-bottom: 1rem;
    width: 70%;
}

.skeleton-hero__body {
    width: 90%;
}

.skeleton-hero__actions {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
}

.skeleton-hero__button {
    width: 8rem;
    height: 2.75rem;
    border-radius: 0.5rem;
}

/* ---------- Skeleton Table ---------- */

.skeleton-table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
}

.skeleton-table th,
.skeleton-table td {
    padding: 0.75rem 1rem;
    text-align: left;
    border-bottom: 1px solid var(--skeleton-border);
}

.skeleton-table th {
    background: var(--skeleton-highlight);
}

/* ---------- Skeleton Grid ---------- */

.skeleton-grid {
    display: grid;
    gap: 1.25rem;
}

.skeleton-grid--2col {
    grid-template-columns: repeat(2, 1fr);
}

.skeleton-grid--3col {
    grid-template-columns: repeat(3, 1fr);
}

.skeleton-grid--4col {
    grid-template-columns: repeat(4, 1fr);
}

/* XL: Desktop grid adjustments */
@media (max-width: 1220px) {
    .skeleton-grid--4col {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* LG: Small laptop */
@media (max-width: 1024px) {
    .skeleton-grid--3col,
    .skeleton-grid--4col {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* MD: Tablet */
@media (max-width: 768px) {
    .skeleton-grid--2col,
    .skeleton-grid--3col,
    .skeleton-grid--4col {
        grid-template-columns: 1fr;
    }
}

/* ---------- Skeleton Button ---------- */

.skeleton-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 2.75rem;
    padding: 0 1.5rem;
    border-radius: 0.5rem;
    min-width: 6rem;
}

/* ---------- Skeleton Avatar ---------- */

.skeleton-avatar {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.skeleton-avatar__info {
    display: flex;
    flex-direction: column;
    gap: 0.375rem;
}

/* ---------- Skeleton Navbar ---------- */

.skeleton-navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    background: var(--skeleton-card);
    border: 1px solid var(--skeleton-border);
}

.skeleton-navbar__brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.skeleton-navbar__nav {
    display: flex;
    gap: 1.25rem;
}

.skeleton-navbar__nav-item {
    width: 5rem;
    height: 1rem;
}

/* ---------- Skeleton Stagger Animation ---------- */

.skeleton-stagger > * {
    opacity: 0;
    animation: skeleton-fade-in 0.3s ease-out forwards;
}

.skeleton-stagger > *:nth-child(1) { animation-delay: 0ms; }
.skeleton-stagger > *:nth-child(2) { animation-delay: 80ms; }
.skeleton-stagger > *:nth-child(3) { animation-delay: 160ms; }
.skeleton-stagger > *:nth-child(4) { animation-delay: 240ms; }
.skeleton-stagger > *:nth-child(5) { animation-delay: 320ms; }
.skeleton-stagger > *:nth-child(6) { animation-delay: 400ms; }
.skeleton-stagger > *:nth-child(7) { animation-delay: 480ms; }
.skeleton-stagger > *:nth-child(8) { animation-delay: 560ms; }
.skeleton-stagger > *:nth-child(9) { animation-delay: 640ms; }
.skeleton-stagger > *:nth-child(10) { animation-delay: 720ms; }

@keyframes skeleton-fade-in {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* ---------- Utility: Skeleton Wrapper ---------- */

.skeleton-wrapper {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.skeleton-wrapper--center {
    align-items: center;
    justify-content: center;
    min-height: 12rem;
}

/* ---------- Width Utilities ---------- */

.skeleton-w-xs {
    width: 3rem;
}

.skeleton-w-sm {
    width: 55%;
}

.skeleton-w-md {
    width: 75%;
}

.skeleton-w-lg {
    width: 90%;
}

.skeleton-w-xl {
    width: 6rem;
}

.skeleton-w-full {
    width: 100%;
}

/* ---------- Height Utilities ---------- */

.skeleton-h-xs {
    height: 0.625rem;
}

.skeleton-h-sm {
    height: 0.875rem;
}

.skeleton-h-md {
    height: 1.1rem;
}

.skeleton-h-lg {
    height: 1.5rem;
}

.skeleton-h-xl {
    height: 2rem;
}

/* ---------- Radius Utilities ---------- */

.skeleton-r-sm {
    border-radius: 0.25rem;
}

.skeleton-r-md {
    border-radius: 0.5rem;
}

.skeleton-r-lg {
    border-radius: 0.75rem;
}

.skeleton-r-full {
    border-radius: 9999px;
}

/* ---------- Layout Utilities ---------- */

.skeleton-flex-1 {
    flex: 1;
}

.skeleton-mb-md {
    margin-bottom: 1rem;
}

.skeleton-w-btn-sm {
    width: 5rem;
}

.skeleton-w-btn-md {
    width: 6rem;
}

/* ---------- Screen Reader Only ---------- */

.skeleton-sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}