/**
 * Global Loader - 2x2 colored blocks with staggered pulse animation
 * Professional, smooth; full-page and inline button states.
 */

/* Full-page overlay */
.app-loader {
    position: fixed;
    inset: 0;
    z-index: 99999;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #fff;
    transition: opacity 0.35s ease, visibility 0.35s ease;
}
.app-loader.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

/* 2x2 grid of blocks - full page */
.loader-blocks {
    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-template-rows: 1fr 1fr;
    gap: 8px;
    width: 52px;
    height: 52px;
}
.loader-blocks .block {
    width: 100%;
    height: 100%;
    border-radius: 8px;
    animation: loader-pulse 0.9s ease-in-out infinite both;
    will-change: transform;
}
.loader-blocks .block:nth-child(1) { background: #7c3aed; animation-delay: 0s; }
.loader-blocks .block:nth-child(2) { background: #f97316; animation-delay: 0.12s; }
.loader-blocks .block:nth-child(3) { background: #7c3aed; animation-delay: 0.24s; }
.loader-blocks .block:nth-child(4) { background: #ec4899; animation-delay: 0.36s; }

/* Staggered pulse: each block scales up then back in sequence */
@keyframes loader-pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.4); }
}

/* Inline / small loader (buttons) */
.loader-inline {
    display: inline-grid;
    grid-template-columns: 1fr 1fr;
    grid-template-rows: 1fr 1fr;
    gap: 2px;
    width: 22px;
    height: 22px;
    vertical-align: middle;
}
.loader-inline .block {
    width: 100%;
    height: 100%;
    border-radius: 3px;
    animation: loader-pulse 0.9s ease-in-out infinite both;
    will-change: transform;
}
.loader-inline .block:nth-child(1) { background: #7c3aed; animation-delay: 0s; }
.loader-inline .block:nth-child(2) { background: #f97316; animation-delay: 0.12s; }
.loader-inline .block:nth-child(3) { background: #7c3aed; animation-delay: 0.24s; }
.loader-inline .block:nth-child(4) { background: #ec4899; animation-delay: 0.36s; }

/* Reduce motion (accessibility) */
@media (prefers-reduced-motion: reduce) {
    .loader-blocks .block,
    .loader-inline .block {
        animation: none;
        transform: scale(1);
    }
}

/* Button loading state */
.btn-loading {
    position: relative;
    pointer-events: none;
}
.btn-loading .btn-text,
.btn-loading .btn-icon {
    visibility: hidden;
}
.btn-loading .loader-inline {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    margin: 0;
}