/**
 * Modern AJAX Loader Styles
 * Полноэкранный оверлей с современным CSS-спиннером
 * Created: 2026-02-04
 */

/* ================================================================ *
   Fullscreen Overlay
 * ================================================================ */
#ajax-loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.55);
    z-index: 10000;
    display: none;
    justify-content: center;
    align-items: center;
    backdrop-filter: blur(2px);
    -webkit-backdrop-filter: blur(2px);
    transition: opacity 0.2s ease-in-out;
}

#ajax-loading-overlay.is-visible {
    display: flex;
}

#ajax-loading-overlay.is-hiding {
    opacity: 0;
}

/* ================================================================ *
   Inner Loading Box
 * ================================================================ */
.ajax-loading-box {
    background: #2a2a2a;
    border-radius: 12px;
    padding: 28px 36px;
    box-shadow: 
        0 10px 40px rgba(0, 0, 0, 0.4),
        0 0 0 1px rgba(255, 255, 255, 0.1);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    min-width: 140px;
    animation: fadeInUp 0.25s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(10px) scale(0.98);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

/* ================================================================ *
   CSS Spinner (Border-style)
 * ================================================================ */
.ajax-spinner {
    width: 44px;
    height: 44px;
    border: 3px solid rgba(255, 255, 255, 0.15);
    border-top-color: #3498db;
    border-radius: 50%;
    animation: spin 0.85s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* ================================================================ *
   Loading Text
 * ================================================================ */
.ajax-loading-text {
    color: #e0e0e0;
    font-size: 14px;
    font-weight: 500;
    letter-spacing: 0.3px;
    text-align: center;
    margin: 0;
}

/* ================================================================ *
   Inline/Button Spinner (для быстрых операций)
 * ================================================================ */
.ajax-spinner-inline {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid rgba(0, 0, 0, 0.15);
    border-top-color: #3498db;
    border-radius: 50%;
    animation: spin 0.75s linear infinite;
    vertical-align: middle;
}

/* Светлая версия для кнопок с тёмным фоном */
.ajax-spinner-inline.spinner-light {
    border-color: rgba(255, 255, 255, 0.2);
    border-top-color: #fff;
}

/* Состояние кнопки при загрузке */
.btn-loading {
    position: relative;
    pointer-events: none;
    opacity: 0.7;
}

.btn-loading .btn-text {
    visibility: hidden;
}

.btn-loading .ajax-spinner-inline {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

/* Альтернативный вариант: спиннер рядом с текстом */
.btn-with-spinner {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.btn-with-spinner .ajax-spinner-inline {
    flex-shrink: 0;
}

/* ================================================================ *
   Accessibility
 * ================================================================ */
#ajax-loading-overlay[aria-busy="true"] {
    cursor: wait;
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
    .ajax-spinner,
    .ajax-spinner-inline {
        animation-duration: 1.5s;
    }
    
    .ajax-loading-box {
        animation: none;
    }
    
    #ajax-loading-overlay {
        transition: none;
    }
}

/* ================================================================ *
   Responsive adjustments
 * ================================================================ */
@media (max-width: 480px) {
    .ajax-loading-box {
        padding: 22px 28px;
        min-width: 120px;
        border-radius: 10px;
    }
    
    .ajax-spinner {
        width: 36px;
        height: 36px;
    }
    
    .ajax-loading-text {
        font-size: 13px;
    }
}