/**
 * Modern CSS Animations 2025
 * High-quality animations with modern design trends
 * Features: Glassmorphism, Smooth transitions, Micro-interactions, Parallax effects
 */

/* ============================================
   CSS Variables for Animation Control
   ============================================ */
:root {
    --anim-duration-fast: 0.2s;
    --anim-duration-normal: 0.3s;
    --anim-duration-slow: 0.6s;
    --anim-easing-smooth: cubic-bezier(0.4, 0, 0.2, 1);
    --anim-easing-bounce: cubic-bezier(0.68, -0.55, 0.265, 1.55);
    --anim-easing-elastic: cubic-bezier(0.175, 0.885, 0.32, 1.275);
    
    /* Glassmorphism */
    --glass-bg: rgba(255, 255, 255, 0.1);
    --glass-border: rgba(255, 255, 255, 0.2);
    --glass-blur: blur(10px);
    
    /* Gradient animations */
    --gradient-1: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-2: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-3: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
}

/* ============================================
   Page Load Animations
   ============================================ */

/* Fade in page on load */
@keyframes fadeInPage {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

body {
    animation: fadeInPage var(--anim-duration-slow) var(--anim-easing-smooth);
}

/* Stagger animation for children */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-up {
    animation: fadeInUp var(--anim-duration-normal) var(--anim-easing-smooth) both;
}

.fade-in-up-delay-1 { animation-delay: 0.1s; }
.fade-in-up-delay-2 { animation-delay: 0.2s; }
.fade-in-up-delay-3 { animation-delay: 0.3s; }
.fade-in-up-delay-4 { animation-delay: 0.4s; }

/* ============================================
   Navigation Animations
   ============================================ */

/* Navbar slide down on scroll */
.navbar {
    transition: transform var(--anim-duration-normal) var(--anim-easing-smooth),
                background-color var(--anim-duration-normal) var(--anim-easing-smooth),
                box-shadow var(--anim-duration-normal) var(--anim-easing-smooth);
}

.navbar.scrolled {
    transform: translateY(0);
    backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.9);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
}

/* Nav link hover with underline animation */
.nav-link {
    position: relative;
    transition: color var(--anim-duration-fast) var(--anim-easing-smooth);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-1);
    transition: width var(--anim-duration-normal) var(--anim-easing-smooth);
    border-radius: 2px;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.nav-link:hover {
    color: #667eea;
    transform: translateY(-2px);
    transition: all var(--anim-duration-fast) var(--anim-easing-smooth);
}

/* Logo animation */
.logo-link {
    transition: transform var(--anim-duration-normal) var(--anim-easing-bounce);
}

.logo-link:hover {
    transform: scale(1.05) rotate(-2deg);
}

.logo-text {
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    transition: all var(--anim-duration-normal) var(--anim-easing-smooth);
}

/* ============================================
   Button Animations
   ============================================ */

@keyframes buttonPulse {
    0%, 100% {
        transform: scale(1);
        box-shadow: 0 0 0 0 rgba(102, 126, 234, 0.7);
    }
    50% {
        transform: scale(1.05);
        box-shadow: 0 0 0 10px rgba(102, 126, 234, 0);
    }
}

.btn {
    position: relative;
    overflow: hidden;
    transition: all var(--anim-duration-normal) var(--anim-easing-smooth);
    transform-style: preserve-3d;
}

.btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width var(--anim-duration-slow), height var(--anim-duration-slow);
}

.btn:hover::before {
    width: 300px;
    height: 300px;
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.3);
}

.btn:active {
    transform: translateY(-1px) scale(0.98);
}

.btn-primary {
    background: var(--gradient-1);
    position: relative;
    overflow: hidden;
}

.btn-primary::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left var(--anim-duration-slow);
}

.btn-primary:hover::after {
    left: 100%;
}

/* ============================================
   Card Animations
   ============================================ */

@keyframes cardFloat {
    0%, 100% {
        transform: translateY(0) rotate(0deg);
    }
    50% {
        transform: translateY(-10px) rotate(1deg);
    }
}

.project-card,
.course-preview-card,
.dashboard-card {
    transition: all var(--anim-duration-normal) var(--anim-easing-smooth);
    position: relative;
    overflow: hidden;
}

.project-card::before,
.course-preview-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transition: left var(--anim-duration-slow);
}

.project-card:hover::before,
.course-preview-card:hover::before {
    left: 100%;
}

.project-card:hover,
.course-preview-card:hover,
.dashboard-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

/* Glassmorphism effect */
.glass-card {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    transition: all var(--anim-duration-normal) var(--anim-easing-smooth);
}

.glass-card:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.3);
    transform: translateY(-5px);
}

/* ============================================
   Text Animations
   ============================================ */

@keyframes gradientShift {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

.gradient-text {
    background: var(--gradient-1);
    background-size: 200% 200%;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradientShift 3s ease infinite;
}

/* Typewriter effect */
@keyframes typewriter {
    from {
        width: 0;
    }
    to {
        width: 100%;
    }
}

.typewriter {
    overflow: hidden;
    border-right: 2px solid;
    white-space: nowrap;
    animation: typewriter 3s steps(40) 1s both,
               blink-caret 0.75s step-end infinite;
}

@keyframes blink-caret {
    from, to {
        border-color: transparent;
    }
    50% {
        border-color: currentColor;
    }
}

/* ============================================
   Image Animations
   ============================================ */

@keyframes imageZoom {
    from {
        transform: scale(1);
    }
    to {
        transform: scale(1.1);
    }
}

.hero-image,
.project-image {
    transition: transform var(--anim-duration-slow) var(--anim-easing-smooth);
    overflow: hidden;
}

.hero-image:hover,
.project-image:hover {
    transform: scale(1.1);
}

.hero-image img,
.project-image img {
    transition: transform var(--anim-duration-slow) var(--anim-easing-smooth);
}

.hero-image:hover img,
.project-image:hover img {
    transform: scale(1.15);
}

/* Parallax effect */
.parallax {
    transition: transform var(--anim-duration-slow) var(--anim-easing-smooth);
}

/* ============================================
   Loading Animations
   ============================================ */

@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.loader {
    border: 3px solid rgba(102, 126, 234, 0.1);
    border-top: 3px solid #667eea;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
}

.pulse {
    animation: pulse 2s ease-in-out infinite;
}

/* ============================================
   Scroll Animations
   ============================================ */

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.slide-in-left {
    animation: slideInLeft var(--anim-duration-normal) var(--anim-easing-smooth) both;
}

.slide-in-right {
    animation: slideInRight var(--anim-duration-normal) var(--anim-easing-smooth) both;
}

/* Intersection Observer triggered animations */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: all var(--anim-duration-slow) var(--anim-easing-smooth);
}

.animate-on-scroll.animated {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   Hover Effects
   ============================================ */

/* Magnetic effect */
.magnetic {
    transition: transform var(--anim-duration-fast) var(--anim-easing-smooth);
}

.magnetic:hover {
    transform: scale(1.1);
}

/* Glow effect */
.glow {
    transition: box-shadow var(--anim-duration-normal) var(--anim-easing-smooth);
}

.glow:hover {
    box-shadow: 0 0 20px rgba(102, 126, 234, 0.5),
                0 0 40px rgba(102, 126, 234, 0.3),
                0 0 60px rgba(102, 126, 234, 0.1);
}

/* ============================================
   Section Transitions
   ============================================ */

.section {
    opacity: 0;
    transform: translateY(50px);
    transition: all var(--anim-duration-slow) var(--anim-easing-smooth);
}

.section.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   Form Animations
   ============================================ */

.form-group input,
.form-group textarea {
    transition: all var(--anim-duration-normal) var(--anim-easing-smooth);
}

.form-group input:focus,
.form-group textarea:focus {
    transform: scale(1.02);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

/* Input label animation */
.form-group {
    position: relative;
}

.form-group label {
    transition: all var(--anim-duration-normal) var(--anim-easing-smooth);
}

.form-group input:focus + label,
.form-group input:not(:placeholder-shown) + label {
    transform: translateY(-20px) scale(0.9);
    color: #667eea;
}

/* ============================================
   Modern 2025 Design Trends
   ============================================ */

/* Neumorphism (subtle) */
.neumorphic {
    background: #E8D5B7;
    box-shadow: 8px 8px 16px rgba(0, 0, 0, 0.1),
                -8px -8px 16px rgba(255, 255, 255, 0.5);
    transition: all var(--anim-duration-normal) var(--anim-easing-smooth);
}

.neumorphic:hover {
    box-shadow: 4px 4px 8px rgba(0, 0, 0, 0.1),
                -4px -4px 8px rgba(255, 255, 255, 0.5);
    transform: translateY(2px);
}

/* Blur backdrop */
.backdrop-blur {
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    background: rgba(255, 255, 255, 0.1);
}

/* Gradient borders */
.gradient-border {
    position: relative;
    background: white;
    border-radius: 10px;
}

.gradient-border::before {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: 10px;
    padding: 2px;
    background: var(--gradient-1);
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
}

/* ============================================
   Responsive Animations
   ============================================ */

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

/* ============================================
   Dark Mode Support
   ============================================ */

[data-theme="dark"] {
    --glass-bg: rgba(0, 0, 0, 0.3);
    --glass-border: rgba(255, 255, 255, 0.1);
}

[data-theme="dark"] .glass-card {
    background: var(--glass-bg);
    border-color: var(--glass-border);
}

[data-theme="dark"] .neumorphic {
    background: #1a1a1a;
    box-shadow: 8px 8px 16px rgba(0, 0, 0, 0.5),
                -8px -8px 16px rgba(255, 255, 255, 0.05);
}

/* ============================================
   Performance Optimizations
   ============================================ */

/* Use transform and opacity for better performance */
.will-animate {
    will-change: transform, opacity;
}

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