/* CSS Variables for Theme Colors */
:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --secondary-color: #8b5cf6;
    --accent-color: #ec4899;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    
    /* Dark Theme Colors */
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --border-color: #334155;
    --card-bg: rgba(30, 41, 59, 0.8);
    --glass-bg: rgba(15, 23, 42, 0.7);
    
    /* Light Theme Colors */
    --light-bg-primary: #ffffff;
    --light-bg-secondary: #f8fafc;
    --light-bg-tertiary: #e2e8f0;
    --light-text-primary: #1e293b;
    --light-text-secondary: #475569;
    --light-text-muted: #64748b;
    --light-border-color: #e2e8f0;
    --light-card-bg: rgba(255, 255, 255, 0.9);
    --light-glass-bg: rgba(255, 255, 255, 0.8);
    
    /* Gradients */
    --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%);
    --gradient-4: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1);
    --shadow-2xl: 0 25px 50px rgba(0, 0, 0, 0.25);
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* Typography */
    --font-primary: 'Inter', sans-serif;
    --font-mono: 'Fira Code', monospace;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-primary);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

body.light-theme {
    --bg-primary: var(--light-bg-primary);
    --bg-secondary: var(--light-bg-secondary);
    --bg-tertiary: var(--light-bg-tertiary);
    --text-primary: var(--light-text-primary);
    --text-secondary: var(--light-text-secondary);
    --text-muted: var(--light-text-muted);
    --border-color: var(--light-border-color);
    --card-bg: var(--light-card-bg);
    --glass-bg: var(--light-glass-bg);
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Section Styles */
.section {
    padding: 80px 0;
    position: relative;
}

.section-alt {
    background-color: var(--bg-secondary);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 60px;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: all var(--transition-normal);
}

.navbar.scrolled {
    background: var(--bg-primary);
    box-shadow: var(--shadow-lg);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo .logo-text {
    font-size: 1.5rem;
    font-weight: 700;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--transition-fast);
    position: relative;
}

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

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

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

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    margin: 3px 0;
    transition: var(--transition-fast);
}

.theme-toggle {
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.2rem;
    cursor: pointer;
    padding: 8px;
    border-radius: 50%;
    transition: all var(--transition-fast);
}

.theme-toggle:hover {
    background: var(--bg-tertiary);
    transform: rotate(180deg);
}

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

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
}

.gradient-sphere {
    position: absolute;
    border-radius: 50%;
    filter: blur(100px);
    opacity: 0.3;
    animation: float 6s ease-in-out infinite;
}

.gradient-sphere:nth-child(1) {
    width: 400px;
    height: 400px;
    background: var(--gradient-1);
    top: -200px;
    left: -200px;
    animation-delay: 0s;
}

.gradient-sphere:nth-child(2) {
    width: 300px;
    height: 300px;
    background: var(--gradient-2);
    bottom: -150px;
    right: -150px;
    animation-delay: 2s;
}

.gradient-sphere:nth-child(3) {
    width: 250px;
    height: 250px;
    background: var(--gradient-3);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation-delay: 4s;
}

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

.hero-content {
    text-align: center;
    max-width: 800px;
    padding: 0 20px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 2rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.hero-description {
    font-size: 1.2rem;
    color: var(--text-muted);
    margin-bottom: 2.5rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.highlight {
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-bottom: 2.5rem;
    flex-wrap: wrap;
}

.hero-social {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all var(--transition-fast);
    backdrop-filter: blur(10px);
}

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

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
}

.scroll-arrow {
    width: 30px;
    height: 30px;
    border-right: 2px solid var(--text-muted);
    border-bottom: 2px solid var(--text-muted);
    transform: rotate(45deg);
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateY(0) rotate(45deg); }
    40% { transform: translateY(-10px) rotate(45deg); }
    60% { transform: translateY(-5px) rotate(45deg); }
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    overflow: hidden;
}

.btn-primary {
    background: var(--gradient-1);
    color: white;
}

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

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border-color);
}

.btn-secondary:hover {
    background: var(--bg-tertiary);
    border-color: var(--primary-color);
    transform: translateY(-2px);
}

.btn-full {
    width: 100%;
    justify-content: center;
}

/* About Section */
.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-text p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 2rem;
}

.stat-item {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.about-image {
    display: flex;
    justify-content: center;
}

.image-container {
    position: relative;
    width: 300px;
    height: 300px;
}

.image-placeholder {
    width: 100%;
    height: 100%;
    background: var(--gradient-1);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 4rem;
    box-shadow: var(--shadow-xl);
}

.about-profile-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 20px;
    box-shadow: var(--shadow-xl);
    transition: transform var(--transition-normal);
}

.about-profile-img:hover {
    transform: scale(1.05);
}

/* Skills Section */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.skill-category {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
    backdrop-filter: blur(10px);
    transition: all var(--transition-fast);
}

.skill-category:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-color);
}

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

.category-title i {
    color: var(--primary-color);
}

.skill-item {
    margin-bottom: 1.5rem;
}

.skill-name {
    display: block;
    font-weight: 500;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

.skill-bar {
    width: 100%;
    height: 8px;
    background: var(--bg-tertiary);
    border-radius: 4px;
    overflow: hidden;
}

.skill-progress {
    height: 100%;
    background: var(--gradient-1);
    border-radius: 4px;
    width: 0;
    transition: width 1s ease;
}

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

.project-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    overflow: hidden;
    transition: all var(--transition-fast);
    backdrop-filter: blur(10px);
}

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

.project-image {
    height: 200px;
    background: var(--gradient-1);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.project-placeholder {
    font-size: 3rem;
    color: white;
}

.project-content {
    padding: 1.5rem;
}

.project-title {
    font-size: 1.3rem;
    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-tech {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
}

.tech-tag {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
}

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

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

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

/* Experience Section */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    top: 0;
    bottom: 0;
    width: 2px;
    background: var(--border-color);
    transform: translateX(-50%);
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
    width: 50%;
}

.timeline-item:nth-child(odd) {
    left: 0;
    padding-right: 2rem;
}

.timeline-item:nth-child(even) {
    left: 50%;
    padding-left: 2rem;
}

.timeline-dot {
    position: absolute;
    width: 20px;
    height: 20px;
    background: var(--primary-color);
    border: 4px solid var(--bg-primary);
    border-radius: 50%;
    top: 0;
    z-index: 1;
}

.timeline-item:nth-child(odd) .timeline-dot {
    right: -10px;
}

.timeline-item:nth-child(even) .timeline-dot {
    left: -10px;
}

.timeline-content {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    backdrop-filter: blur(10px);
    transition: all var(--transition-fast);
}

.timeline-content:hover {
    transform: scale(1.02);
    box-shadow: var(--shadow-lg);
}

.timeline-date {
    color: var(--primary-color);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.timeline-title {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
    color: var(--text-primary);
}

.timeline-company {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.timeline-description {
    list-style: none;
}

.timeline-description li {
    color: var(--text-muted);
    margin-bottom: 0.5rem;
    position: relative;
    padding-left: 1.5rem;
}

.timeline-description li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--primary-color);
}

/* Contact Section */
.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: start;
}

.contact-info h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.contact-info p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    line-height: 1.6;
}

.contact-details {
    margin-bottom: 2rem;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

.contact-item i {
    color: var(--primary-color);
    width: 20px;
}

.contact-social {
    display: flex;
    gap: 1rem;
}

.social-link-large {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-tertiary);
    border-radius: 50%;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all var(--transition-fast);
}

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

/* Contact Form */
.contact-form {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
    backdrop-filter: blur(10px);
}

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

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 1rem;
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.form-group label {
    position: absolute;
    left: 1rem;
    top: 1rem;
    color: var(--text-muted);
    transition: all var(--transition-fast);
    pointer-events: none;
}

.form-group input:focus + label,
.form-group input:not(:placeholder-shown) + label,
.form-group textarea:focus + label,
.form-group textarea:not(:placeholder-shown) + label {
    top: -0.5rem;
    left: 0.5rem;
    font-size: 0.85rem;
    background: var(--bg-primary);
    padding: 0 0.5rem;
    color: var(--primary-color);
}

/* Footer */
.footer {
    background: var(--bg-secondary);
    padding: 2rem 0;
    border-top: 1px solid var(--border-color);
}

.footer-content {
    text-align: center;
    color: var(--text-muted);
}

.footer-content p {
    margin-bottom: 0.5rem;
}

.footer-content i {
    color: var(--error-color);
}

.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    border: none;
    border-radius: 50%;
    color: white;
    font-size: 1.2rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-fast);
    z-index: 999;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

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

/* Animations */
.animate-fade-in {
    opacity: 0;
    transform: translateY(30px);
    animation: fadeInUp 0.8s ease forwards;
}

.animate-delay-1 {
    animation-delay: 0.1s;
}

.animate-delay-2 {
    animation-delay: 0.2s;
}

.animate-delay-3 {
    animation-delay: 0.3s;
}

.animate-delay-4 {
    animation-delay: 0.4s;
}

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

.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

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

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: var(--bg-primary);
        width: 100%;
        text-align: center;
        transition: var(--transition-fast);
        box-shadow: var(--shadow-lg);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-toggle.active .bar:nth-child(2) {
        opacity: 0;
    }

    .nav-toggle.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .nav-toggle.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.5rem;
    }

    .hero-description {
        font-size: 1rem;
    }

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

    .section-title {
        font-size: 2rem;
    }

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

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

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

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

    .timeline::before {
        left: 30px;
    }

    .timeline-item {
        width: 100%;
        left: 0 !important;
        padding-left: 60px !important;
        padding-right: 0 !important;
    }

    .timeline-dot {
        left: 20px !important;
        right: auto !important;
    }

    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .container {
        padding: 0 15px;
    }

    .section {
        padding: 60px 0;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .section-title {
        font-size: 1.8rem;
    }

    .skill-category,
    .project-content,
    .timeline-content,
    .contact-form {
        padding: 1.5rem;
    }

    .btn {
        padding: 10px 20px;
        font-size: 0.9rem;
    }
}

/* Success Message */
.success-message {
    position: fixed;
    top: 100px;
    right: 20px;
    background: var(--success-color);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 8px;
    box-shadow: var(--shadow-lg);
    transform: translateX(400px);
    transition: transform var(--transition-normal);
    z-index: 1001;
}

.success-message.show {
    transform: translateX(0);
}

/* Loading Spinner */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

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