/**
 * Genesis Budget - Loading System
 *
 * CSS-only loader overlay that displays during:
 * - Page loads
 * - AJAX requests
 * - Form submissions
 */

/* ========================================
   FULL PAGE LOADER OVERLAY
   ======================================== */

.gb-loader-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg-overlay, rgba(0, 0, 0, 0.5));
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: var(--z-loader, 700);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-normal, 250ms ease),
                visibility var(--transition-normal, 250ms ease);
}

.gb-loader-overlay.active {
    opacity: 1;
    visibility: visible;
}

/* Prevent body scroll when loader is active */
body.loading {
    overflow: hidden;
}

/* ========================================
   SPINNER ANIMATION
   ======================================== */

.gb-spinner {
    width: 48px;
    height: 48px;
    border: 4px solid var(--border-color, #e5e7eb);
    border-top-color: var(--color-primary, #4f46e5);
    border-radius: 50%;
    animation: gb-spin 0.8s linear infinite;
}

.gb-spinner.spinner-sm {
    width: 24px;
    height: 24px;
    border-width: 2px;
}

.gb-spinner.spinner-lg {
    width: 64px;
    height: 64px;
    border-width: 5px;
}

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

/* ========================================
   LOADER MESSAGE
   ======================================== */

.gb-loader-message {
    margin-top: var(--space-4, 1rem);
    color: var(--text-inverse, #ffffff);
    font-size: var(--font-size-base, 1rem);
    font-weight: var(--font-weight-medium, 500);
    text-align: center;
}

/* ========================================
   INLINE LOADER (For buttons/inputs)
   ======================================== */

.gb-inline-loader {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2, 0.5rem);
}

.gb-inline-loader .gb-spinner {
    width: 16px;
    height: 16px;
    border-width: 2px;
}

/* Button loading state */
.btn.loading,
button.loading {
    position: relative;
    color: transparent !important;
    pointer-events: none;
}

.btn.loading::after,
button.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 18px;
    height: 18px;
    margin: -9px 0 0 -9px;
    border: 2px solid currentColor;
    border-top-color: transparent;
    border-radius: 50%;
    animation: gb-spin 0.8s linear infinite;
    /* Restore color for the spinner */
    color: inherit;
    opacity: 0.9;
}

/* Primary button loading */
.btn-primary.loading::after {
    border-color: rgba(255, 255, 255, 0.3);
    border-top-color: white;
}

/* Secondary/outline button loading */
.btn-secondary.loading::after,
.btn-outline-primary.loading::after {
    border-color: rgba(79, 70, 229, 0.3);
    border-top-color: var(--color-primary, #4f46e5);
}

/* ========================================
   SKELETON LOADER
   ======================================== */

.gb-skeleton {
    background: linear-gradient(
        90deg,
        var(--color-gray-200, #e5e7eb) 25%,
        var(--color-gray-100, #f3f4f6) 50%,
        var(--color-gray-200, #e5e7eb) 75%
    );
    background-size: 200% 100%;
    animation: gb-skeleton-shimmer 1.5s ease-in-out infinite;
    border-radius: var(--border-radius-sm, 4px);
}

@keyframes gb-skeleton-shimmer {
    0% {
        background-position: 200% 0;
    }
    100% {
        background-position: -200% 0;
    }
}

/* Skeleton variants */
.gb-skeleton-text {
    height: 1em;
    margin-bottom: 0.5em;
}

.gb-skeleton-text:last-child {
    width: 70%;
}

.gb-skeleton-title {
    height: 1.5em;
    width: 60%;
    margin-bottom: 1em;
}

.gb-skeleton-avatar {
    width: 48px;
    height: 48px;
    border-radius: 50%;
}

.gb-skeleton-card {
    height: 120px;
    border-radius: var(--border-radius, 8px);
}

.gb-skeleton-button {
    height: 38px;
    width: 100px;
    border-radius: var(--border-radius-sm, 4px);
}

/* Dark mode skeletons */
[data-theme="dark"] .gb-skeleton,
.dark-mode .gb-skeleton {
    background: linear-gradient(
        90deg,
        var(--color-gray-700, #374151) 25%,
        var(--color-gray-600, #4b5563) 50%,
        var(--color-gray-700, #374151) 75%
    );
    background-size: 200% 100%;
}

/* ========================================
   PROGRESS BAR LOADER
   ======================================== */

.gb-progress-loader {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--color-gray-200, #e5e7eb);
    z-index: var(--z-loader, 700);
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-fast, 150ms ease);
}

.gb-progress-loader.active {
    opacity: 1;
    visibility: visible;
}

.gb-progress-loader::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 30%;
    background: var(--color-primary, #4f46e5);
    animation: gb-progress 1.5s ease-in-out infinite;
}

@keyframes gb-progress {
    0% {
        left: -30%;
    }
    100% {
        left: 100%;
    }
}

/* ========================================
   DOTS LOADER (Alternative style)
   ======================================== */

.gb-dots-loader {
    display: inline-flex;
    gap: 4px;
}

.gb-dots-loader span {
    width: 8px;
    height: 8px;
    background: var(--color-primary, #4f46e5);
    border-radius: 50%;
    animation: gb-dots-bounce 1.4s ease-in-out infinite both;
}

.gb-dots-loader span:nth-child(1) {
    animation-delay: -0.32s;
}

.gb-dots-loader span:nth-child(2) {
    animation-delay: -0.16s;
}

@keyframes gb-dots-bounce {
    0%, 80%, 100% {
        transform: scale(0);
    }
    40% {
        transform: scale(1);
    }
}

/* ========================================
   COMPONENT LOADING STATE
   ======================================== */

.gb-loading-container {
    position: relative;
    min-height: 100px;
}

.gb-loading-container.loading::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg-card, #ffffff);
    opacity: 0.8;
    z-index: 1;
}

.gb-loading-container.loading::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 32px;
    height: 32px;
    margin: -16px 0 0 -16px;
    border: 3px solid var(--border-color, #e5e7eb);
    border-top-color: var(--color-primary, #4f46e5);
    border-radius: 50%;
    animation: gb-spin 0.8s linear infinite;
    z-index: 2;
}

/* ========================================
   DISABLED STATE DURING LOADING
   ======================================== */

.gb-disabled-during-load {
    pointer-events: none;
    opacity: 0.6;
}