/* Variables - Default Theme */
:root {
    --primary-blue: #1e88e5;
    --primary-orange: #ff9800;
    --secondary-blue: #64b5f6;
    --secondary-orange: #ffb74d;
    --dark-blue: #0d47a1;
    --light-orange: #ffe0b2;
    --gradient-primary: linear-gradient(135deg, var(--primary-blue) 0%, var(--primary-orange) 100%);
    --gradient-light: linear-gradient(135deg, var(--secondary-blue) 0%, var(--secondary-orange) 100%);
    --bg-color: #f8f9fa;
    --card-bg: #ffffff;
    --text-primary: #2c3e50;
    --text-muted: #6c757d;
    --border-color: #e9ecef;
    --shadow-light: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-medium: 0 4px 6px rgba(0,0,0,0.1);
    --shadow-heavy: 0 8px 15px rgba(0,0,0,0.1);
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --border-radius: 10px;
    --border-radius-large: 15px;
}

/* Enhanced CSS Variables for better theming */
:root {
    --success-color: #4caf50;
    --warning-color: #ff9800;
    --error-color: #f44336;
    --info-color: #2196f3;
    --text-color: var(--text-primary);
    --text-secondary: var(--text-muted);
    --bg-secondary: rgba(0,0,0,0.05);
    --input-bg: var(--card-bg);
    --primary-color: var(--primary-blue);
}

[data-theme="dark"] {
    --success-color: #66bb6a;
    --warning-color: #ffb74d;
    --error-color: #ef5350;
    --info-color: #42a5f5;
    --bg-secondary: rgba(255,255,255,0.05);
}

/* Spinning animation for loaders */
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.spin {
    animation: spin 1s linear infinite;
}

/* Enhanced gradient animations */
@keyframes gradient-shift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.gradient-animated {
    background-size: 200% 200%;
    animation: gradient-shift 3s ease infinite;
}

/* Dark Theme */
[data-theme="dark"] {
    --primary-blue: #4fc3f7;
    --primary-orange: #ffb74d;
    --secondary-blue: #81c784;
    --secondary-orange: #ffcc02;
    --dark-blue: #1565c0;
    --light-orange: #fff3e0;
    --gradient-primary: linear-gradient(135deg, #1565c0 0%, #ff8f00 100%);
    --gradient-light: linear-gradient(135deg, #4fc3f7 0%, #ffb74d 100%);
    --bg-color: #121212;
    --card-bg: #1e1e1e;
    --text-primary: #ffffff;
    --text-muted: #b0b0b0;
    --border-color: #333333;
    --shadow-light: 0 2px 4px rgba(0,0,0,0.3);
    --shadow-medium: 0 4px 6px rgba(0,0,0,0.3);
    --shadow-heavy: 0 8px 15px rgba(0,0,0,0.3);
}

/* Ocean Theme */
[data-theme="ocean"] {
    --primary-blue: #006064;
    --primary-orange: #00acc1;
    --secondary-blue: #4dd0e1;
    --secondary-orange: #80deea;
    --dark-blue: #004d5c;
    --light-orange: #e0f2f1;
    --gradient-primary: linear-gradient(135deg, #006064 0%, #00acc1 100%);
    --gradient-light: linear-gradient(135deg, #4dd0e1 0%, #80deea 100%);
}

/* Forest Theme */
[data-theme="forest"] {
    --primary-blue: #2e7d32;
    --primary-orange: #689f38;
    --secondary-blue: #66bb6a;
    --secondary-orange: #9ccc65;
    --dark-blue: #1b5e20;
    --light-orange: #f1f8e9;
    --gradient-primary: linear-gradient(135deg, #2e7d32 0%, #689f38 100%);
    --gradient-light: linear-gradient(135deg, #66bb6a 0%, #9ccc65 100%);
}

/* Sunset Theme */
[data-theme="sunset"] {
    --primary-blue: #d32f2f;
    --primary-orange: #ff5722;
    --secondary-blue: #f44336;
    --secondary-orange: #ff7043;
    --dark-blue: #b71c1c;
    --light-orange: #ffebee;
    --gradient-primary: linear-gradient(135deg, #d32f2f 0%, #ff5722 100%);
    --gradient-light: linear-gradient(135deg, #f44336 0%, #ff7043 100%);
}

/* Performance optimizations */
* {
    box-sizing: border-box;
}

*::before,
*::after {
    box-sizing: border-box;
}

/* General Styles */
body {
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: linear-gradient(135deg, var(--bg-color) 0%, var(--light-orange) 100%);
    background-attachment: fixed;
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transition: background-color var(--transition-normal), color var(--transition-normal);
    min-height: 100vh;
}

/* Enhanced container styling */
.container {
    position: relative;
    z-index: 1;
}

/* Glass morphism effect for cards */
.card {
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

[data-theme="dark"] .card {
    background: rgba(30, 30, 30, 0.9);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

/* Lazy loading optimization */
img {
    loading: lazy;
    max-width: 100%;
    height: auto;
}

/* Reduce layout shifts */
.card-img-top {
    aspect-ratio: 16/9;
    object-fit: cover;
}

/* Navigation */
.navbar {
    background: rgba(255, 255, 255, 0.95);
    box-shadow: var(--shadow-medium);
    padding: 1rem 0;
    transition: all var(--transition-normal);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    position: sticky;
    top: 0;
    z-index: 9999 !important;
}

.navbar .dropdown-menu {
    z-index: 10000 !important;
}

.navbar .nav-item,
.navbar .dropdown {
    z-index: 9999 !important;
}

[data-theme="dark"] .navbar {
    background: rgba(30, 30, 30, 0.95);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.navbar-brand {
    font-size: 1.6rem;
    font-weight: 800;
    text-decoration: none;
    transition: transform var(--transition-normal);
}

.navbar-brand:hover {
    transform: scale(1.05);
}

.navbar-brand {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: 700;
}

.navbar-brand i {
    margin-right: 0.5rem;
    color: var(--primary-blue);
}

.brand-text .elevate {
    color: var(--primary-blue);
}

.brand-text .ed {
    color: var(--primary-orange);
}

.nav-link {
    font-weight: 500;
    color: var(--text-primary);
    margin: 0 0.5rem;
    padding: 0.5rem 1rem !important;
    border-radius: var(--border-radius);
    transition: all var(--transition-normal);
}

.nav-link:hover {
    background-color: var(--light-orange);
    color: var(--dark-blue);
    transform: translateY(-2px);
}

.dropdown-menu {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-medium);
    border-radius: var(--border-radius);
    z-index: 9999 !important;
    position: absolute !important;
}

.dropdown-item {
    color: var(--text-primary);
    transition: background-color var(--transition-fast);
}

.dropdown-item:hover {
    background-color: var(--light-orange);
    color: var(--dark-blue);
}

/* Cards */
.card {
    border: none;
    border-radius: var(--border-radius-large);
    box-shadow: var(--shadow-medium);
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
    overflow: hidden;
    background-color: var(--card-bg);
    will-change: transform;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-heavy);
}

.card-body {
    color: var(--text-primary);
}

.card-header {
    background-color: var(--card-bg);
    border-bottom: 1px solid var(--border-color);
    color: var(--text-primary);
}

/* Hero Section */
.hero-section {
    background: var(--gradient-primary);
    color: white;
    padding: 6rem 0;
    border-radius: 20px;
    margin-bottom: 3rem;
    position: relative;
    overflow: hidden;
    will-change: background;
    box-shadow: var(--shadow-heavy);
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(45deg, rgba(0,0,0,0.2) 0%, rgba(0,0,0,0) 100%);
    z-index: 1;
}

.hero-section::after {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: float 6s ease-in-out infinite;
    z-index: 1;
}

@keyframes float {
    0%, 100% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(180deg); }
}

.hero-content {
    position: relative;
    z-index: 2;
}

/* Enhanced button animations */
.btn {
    position: relative;
    overflow: hidden;
    transform-style: preserve-3d;
}

.btn::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: rgba(255,255,255,0.2);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn:active::after {
    width: 300px;
    height: 300px;
}

/* Buttons */
.btn {
    border-radius: var(--border-radius);
    padding: 0.8rem 2rem;
    font-weight: 600;
    transition: all var(--transition-normal);
    will-change: transform;
}

.btn-primary {
    background: var(--gradient-primary);
    border: none;
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(30,136,229,0.3);
}

.btn-outline-primary {
    border-color: var(--primary-blue);
    color: var(--primary-blue);
}

.btn-outline-primary:hover {
    background-color: var(--primary-blue);
    border-color: var(--primary-blue);
}

/* Features Section */
.feature-card {
    padding: 2rem;
    text-align: center;
    background: var(--card-bg);
    transition: background-color var(--transition-normal);
}

.feature-icon {
    width: 60px;
    height: 60px;
    background: var(--gradient-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
}

.feature-icon i {
    color: white;
    font-size: 24px;
}

/* Footer */
.footer {
    background-color: var(--card-bg);
    border-top: 1px solid var(--border-color);
    color: var(--text-muted);
    transition: background-color var(--transition-normal);
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero-section {
        padding: 4rem 0;
        border-radius: 15px;
    }

    .card {
        margin-bottom: 1.5rem;
    }

    .feature-card {
        margin-bottom: 2rem;
    }
}

/* Performance and accessibility improvements */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Loading states */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

.skeleton {
    background: linear-gradient(90deg, var(--border-color) 25%, transparent 50%, var(--border-color) 75%);
    background-size: 200% 100%;
    animation: loading 1.5s infinite;
}

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

/* Theme transition */
.theme-transition {
    transition: all var(--transition-normal);
}

/* Achievement animations */
@keyframes achievement-bounce {
    0%, 20%, 53%, 80%, 100% {
        transform: translate3d(0, 0, 0);
    }
    40%, 43% {
        transform: translate3d(0, -30px, 0);
    }
    70% {
        transform: translate3d(0, -15px, 0);
    }
    90% {
        transform: translate3d(0, -4px, 0);
    }
}

.achievement-animation {
    animation: achievement-bounce 1s ease-in-out;
}

/* Improved focus states for accessibility */
.btn:focus,
.nav-link:focus,
.dropdown-item:focus {
    outline: 2px solid var(--primary-blue);
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --shadow-light: 0 2px 4px rgba(0,0,0,0.5);
        --shadow-medium: 0 4px 6px rgba(0,0,0,0.5);
        --shadow-heavy: 0 8px 15px rgba(0,0,0,0.5);
    }
}

/* Print styles */
@media print {
    .navbar,
    .footer,
    .btn,
    .dropdown {
        display: none !important;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid #000;
    }
}