/* =================================================================
   PERFORMANCE OPTIMIZATION CSS
   Beautiful Loading System & Performance Enhancements
================================================================= */

/* ===== PAGE LOADER ===== */
.page-loader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #1D7D57 0%, #2A9B68 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    transition: opacity 0.5s ease, visibility 0.5s ease;
}

.page-loader.loaded {
    opacity: 0;
    visibility: hidden;
}

.loader-content {
    text-align: center;
    color: white;
}

.school-logo-loader {
    width: 80px;
    height: 80px;
    margin: 0 auto 20px;
    position: relative;
    animation: logoFloat 2s ease-in-out infinite alternate;
}

.school-logo-loader img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    filter: brightness(0) invert(1);
}

@keyframes logoFloat {
    0% { transform: translateY(0px); }
    100% { transform: translateY(-10px); }
}

.loader-spinner {
    width: 60px;
    height: 60px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-top: 3px solid #ffffff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loader-text {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 10px;
    animation: pulse 1.5s ease-in-out infinite;
}

.loader-subtext {
    font-size: 14px;
    opacity: 0.8;
    animation: fadeInOut 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

@keyframes fadeInOut {
    0%, 100% { opacity: 0.8; }
    50% { opacity: 0.4; }
}

/* Progress Bar */
.loader-progress {
    width: 200px;
    height: 4px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 2px;
    margin: 20px auto 0;
    overflow: hidden;
}

.loader-progress-bar {
    height: 100%;
    background: linear-gradient(90deg, #ffffff, #f0f0f0);
    border-radius: 2px;
    animation: progressAnimation 2s ease-in-out infinite;
    transform: translateX(-100%);
}

@keyframes progressAnimation {
    0% { transform: translateX(-100%); }
    50% { transform: translateX(0%); }
    100% { transform: translateX(100%); }
}

/* ===== SKELETON SCREENS ===== */
.skeleton {
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    border-radius: 4px;
}

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

.skeleton-text {
    height: 16px;
    margin-bottom: 8px;
}

.skeleton-text.large {
    height: 24px;
}

.skeleton-text.small {
    height: 12px;
}

.skeleton-text.short {
    width: 60%;
}

.skeleton-text.medium {
    width: 80%;
}

.skeleton-image {
    width: 100%;
    height: 200px;
    margin-bottom: 16px;
}

.skeleton-card {
    padding: 20px;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    margin-bottom: 20px;
}

/* ===== SMOOTH FADE-IN ANIMATIONS ===== */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

.fade-in-delayed {
    transition-delay: 0.2s;
}

.fade-in-delayed-2 {
    transition-delay: 0.4s;
}

.fade-in-delayed-3 {
    transition-delay: 0.6s;
}

/* ===== LAZY LOADING PLACEHOLDERS ===== */
.lazy-image {
    opacity: 0;
    transition: opacity 0.3s ease;
}

.lazy-image.loaded {
    opacity: 1;
}

.image-placeholder {
    background: #f5f5f5;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #999;
    font-size: 14px;
    min-height: 200px;
}

/* ===== SMOOTH SCROLLING ===== */
html {
    scroll-behavior: smooth;
}

/* ===== PERFORMANCE OPTIMIZATIONS ===== */
.will-change-transform {
    will-change: transform;
}

.will-change-opacity {
    will-change: opacity;
}

.gpu-accelerated {
    transform: translateZ(0);
    backface-visibility: hidden;
    perspective: 1000px;
}

/* ===== RESPONSIVE OPTIMIZATIONS ===== */
@media (max-width: 768px) {
    .school-logo-loader {
        width: 60px;
        height: 60px;
    }

    .loader-spinner {
        width: 40px;
        height: 40px;
    }

    .loader-text {
        font-size: 16px;
    }

    .loader-progress {
        width: 150px;
    }
}

/* ===== CRITICAL CSS INLINE STYLES ===== */
.critical-loading {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: #333;
}

/* Hide content until loaded */
.content-loading {
    visibility: hidden;
}

.content-loaded {
    visibility: visible;
}

/* ===== INTERSECTION OBSERVER OPTIMIZATIONS ===== */
.observe-fade {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.observe-fade.in-view {
    opacity: 1;
    transform: translateY(0);
}

.observe-slide-left {
    opacity: 0;
    transform: translateX(-50px);
    transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.observe-slide-left.in-view {
    opacity: 1;
    transform: translateX(0);
}

.observe-slide-right {
    opacity: 0;
    transform: translateX(50px);
    transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.observe-slide-right.in-view {
    opacity: 1;
    transform: translateX(0);
}

.observe-scale {
    opacity: 0;
    transform: scale(0.8);
    transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.observe-scale.in-view {
    opacity: 1;
    transform: scale(1);
}