:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #06b6d4;
    --accent-color: #f59e0b;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-card: #ffffff;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-accent: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    overflow-x: hidden;
    font-display: swap;
}

/* Critical CSS for above-the-fold content */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-primary);
    color: white;
    text-align: center;
    position: relative;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 4rem);
    font-weight: 700;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.hero-subtitle {
    font-size: clamp(1.2rem, 3vw, 2rem);
    margin-bottom: 1.5rem;
    opacity: 0.9;
}

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

/* Reduce layout shift */
.project-card {
    min-height: 400px;
}

/* Optimize animations for performance */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: all 0.3s ease;
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

.logo:hover {
    color: var(--primary-dark);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

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

.nav-link:hover {
    color: var(--primary-color);
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--text-primary);
    cursor: pointer;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    background: var(--gradient-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grid" width="10" height="10" patternUnits="userSpaceOnUse"><path d="M 10 0 L 0 0 0 10" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="0.5"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>');
    opacity: 0.3;
}

.hero-content {
    text-align: center;
    color: white;
    max-width: 800px;
    padding: 2rem;
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 700;
    margin-bottom: 1rem;
    opacity: 0;
    animation: slideUp 1s ease 0.2s forwards;
}

.hero-subtitle {
    font-size: clamp(1.2rem, 2.5vw, 1.5rem);
    font-weight: 400;
    margin-bottom: 2rem;
    opacity: 0;
    animation: slideUp 1s ease 0.4s forwards;
}

.hero-description {
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 3rem;
    opacity: 0;
    animation: slideUp 1s ease 0.6s forwards;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    opacity: 0;
    animation: slideUp 1s ease 0.8s forwards;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 2rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
    font-size: 1rem;
}

.btn-primary {
    background: white;
    color: var(--primary-color);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-outline {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-outline:hover {
    background: white;
    color: var(--primary-color);
    transform: translateY(-2px);
}

/* Floating Animation */
.floating-elements {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    pointer-events: none;
}

.floating-element {
    position: absolute;
    opacity: 0.1;
    animation: float 6s ease-in-out infinite;
    font-size: 3rem;
}

.floating-element:nth-child(1) {
    top: 20%;
    left: 10%;
    animation-delay: 0s;
}

.floating-element:nth-child(2) {
    top: 60%;
    left: 80%;
    animation-delay: 2s;
}

.floating-element:nth-child(3) {
    top: 80%;
    left: 20%;
    animation-delay: 4s;
}

@keyframes float {

    0%,
    100% {
        transform: translateY(0px) rotate(0deg);
    }

    50% {
        transform: translateY(-20px) rotate(180deg);
    }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Section Styles */
.section {
    padding: 5rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: var(--gradient-primary);
    border-radius: 2px;
}

.section-subtitle {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Projects Grid */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.project-card {
    background: var(--bg-card);
    border-radius: 20px;
    padding: 2rem;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.project-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-primary);
}

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

.project-icon {
    width: 60px;
    height: 60px;
    background: var(--gradient-primary);
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
    color: white;
}

.project-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.project-description {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.tag {
    background: var(--bg-secondary);
    color: var(--text-secondary);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 500;
}

.project-links {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.project-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.project-link:hover {
    color: var(--primary-dark);
}

/* Skills Section */
.skills-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.skill-category {
    background: var(--bg-card);
    padding: 2rem;
    border-radius: 20px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.skill-category-title {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.skill-list {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.skill-item {
    background: var(--gradient-primary);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 25px;
    font-size: 0.9rem;
    font-weight: 500;
}

/* About Section */
.about {
    background: var(--bg-secondary);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 3rem;
    align-items: center;
}

.about-image {
    text-align: center;
}

.profile-image {
    width: 250px;
    height: 250px;
    border-radius: 50%;
    object-fit: cover;
    border: 8px solid white;
    box-shadow: var(--shadow-lg);
}

.about-text {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

.about-text p {
    margin-bottom: 1.5rem;
}

/* Stats Section */
.stats {
    background: var(--gradient-primary);
    color: white;
    text-align: center;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
}

.stat-item {
    padding: 1rem;
}

.stat-number {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* Contact Section */
.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.contact-icon {
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.2rem;
}

.contact-details h3 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.contact-details p {
    color: var(--text-secondary);
}

.contact-form {
    background: var(--bg-card);
    padding: 2rem;
    border-radius: 20px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-color);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-primary);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem;
    border: 2px solid var(--border-color);
    border-radius: 10px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* Footer */
.footer {
    background: var(--text-primary);
    color: white;
    text-align: center;
    padding: 3rem 2rem 2rem;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    color: white;
    text-decoration: none;
    font-size: 1.2rem;
    transition: all 0.3s ease;
}

.social-link:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

/* Scroll to Top Button */
.scroll-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 1.2rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 1000;
}

.scroll-top.visible {
    opacity: 1;
    visibility: visible;
}

.scroll-top:hover {
    background: var(--primary-dark);
    transform: translateY(-3px);
}

/* SSR-friendly Animations */
/* Elements are visible by default (SSR), animations apply after DOMContentLoaded */
.fade-in {
    opacity: 1;
    transform: translateY(0);
}

/* Apply animation properties only when animations are ready */
body.animations-ready .fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

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

.stagger-1 {
    transition-delay: 0.1s;
}

.stagger-2 {
    transition-delay: 0.2s;
}

.stagger-3 {
    transition-delay: 0.3s;
}

.stagger-4 {
    transition-delay: 0.4s;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 2rem;
        box-shadow: var(--shadow-lg);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .mobile-menu-toggle {
        display: block;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .about-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .contact-content {
        grid-template-columns: 1fr;
    }

    .projects-grid {
        grid-template-columns: 1fr;
    }

    .skills-container {
        grid-template-columns: 1fr;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .section {
        padding: 3rem 1rem;
    }

    .nav-container {
        padding: 1rem;
    }

    .project-card {
        padding: 1.5rem;
    }

    .stats-grid {
        grid-template-columns: 1fr;
    }
}