/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Light Theme Variables */
    --primary-color: #3b82f6;
    --secondary-color: #1e40af;
    --accent-color: #f59e0b;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --border-color: #e5e7eb;
    --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-heavy: 0 10px 15px rgba(0, 0, 0, 0.1);
    --gradient-primary: linear-gradient(135deg, #3b82f6 0%, #1e40af 100%);
    --gradient-secondary: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
}

[data-theme="dark"] {
    /* Dark Theme Variables */
    --primary-color: #60a5fa;
    --secondary-color: #3b82f6;
    --accent-color: #fbbf24;
    --text-primary: #f9fafb;
    --text-secondary: #d1d5db;
    --bg-primary: #111827;
    --bg-secondary: #1f2937;
    --bg-tertiary: #374151;
    --border-color: #374151;
    --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-medium: 0 4px 6px rgba(0, 0, 0, 0.3);
    --shadow-heavy: 0 10px 15px rgba(0, 0, 0, 0.3);
    --gradient-primary: linear-gradient(135deg, #60a5fa 0%, #3b82f6 100%);
    --gradient-secondary: linear-gradient(135deg, #fbbf24 0%, #f59e0b 100%);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Poppins', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    transition: all 0.3s ease;
    border-bottom: 1px solid var(--border-color);
}

[data-theme="dark"] .navbar {
    background-color: rgba(17, 24, 39, 0.95);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo h2 {
    color: var(--primary-color);
    font-weight: 600;
}

.nav-logo span {
    color: var(--text-secondary);
    font-weight: 400;
    font-size: 0.9rem;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2rem;
}

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

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

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

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

.cv-btn {
    background: var(--gradient-primary);
    color: white;
    padding: 0.5rem 1.5rem;
    border-radius: 25px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

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

.theme-toggle {
    background: none;
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.theme-toggle:hover {
    background-color: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

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

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: var(--text-primary);
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 70px;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.2;
}

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

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-weight: 500;
}

.hero-description {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
}

.btn {
    padding: 0.75rem 2rem;
    border-radius: 30px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    border: none;
    cursor: pointer;
}

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

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

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

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

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

.social-link {
    width: 45px;
    height: 45px;
    background: var(--bg-tertiary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all 0.3s ease;
}

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

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
    position: relative;
}

.profile-card {
    position: relative;
    animation: float 6s ease-in-out infinite;
}

.profile-img {
    width: 300px;
    height: 300px;
    border-radius: 50%;
    object-fit: cover;
    border: 5px solid var(--primary-color);
    box-shadow: var(--shadow-heavy);
}

.floating-elements {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.floating-icon {
    position: absolute;
    width: 60px;
    height: 60px;
    background: var(--gradient-secondary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5rem;
    animation: float 4s ease-in-out infinite;
}

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

.floating-icon:nth-child(2) {
    bottom: 30%;
    left: -15%;
    animation-delay: 2s;
}

.floating-icon:nth-child(3) {
    top: 60%;
    right: 10%;
    animation-delay: 4s;
}

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

/* Skill Progress Bars */
.progress-bar {
    background: var(--bg-tertiary);
    border-radius: 50px;
    overflow: hidden;
    height: 10px;
    margin-top: 1rem;
    position: relative;
}

.progress {
    background: var(--gradient-primary);
    height: 100%;
    width: 0%;
    transition: width 1.5s ease-in-out;
    border-radius: 50px;
    position: relative;
}

.progress::after {
    content: attr(data-level);
    position: absolute;
    top: -25px;
    right: 0;
    font-size: 0.8rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* Section Titles */
.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-primary);
}

.section-title::after {
    content: '';
    display: block;
    width: 100px;
    height: 4px;
    background: var(--gradient-primary);
    margin: 1rem auto;
    border-radius: 2px;
}

/* About Section */
.about {
    padding: 5rem 0;
    background-color: var(--bg-secondary);
}

.about-content {
    max-width: 1000px;
    margin: 0 auto;
}

.about-text {
    text-align: center;
    margin-bottom: 3rem;
}

.about-text p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 2rem;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.skill-category {
    background: var(--bg-primary);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow-light);
    text-align: center;
    transition: all 0.3s ease;
}

.skill-category:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-medium);
}

.skill-category h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.skills {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
}

.skill-tag {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
}

/* Projects Section */
.projects {
    padding: 5rem 0;
    background-color: var(--bg-primary);
}

.projects-filter {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.filter-btn {
    background: transparent;
    border: 2px solid var(--border-color);
    color: var(--text-secondary);
    padding: 0.5rem 1.5rem;
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
}

.filter-btn.active,
.filter-btn:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

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

.project-card {
    background: var(--bg-secondary);
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--shadow-light);
    transition: all 0.3s ease;
    position: relative;
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-heavy);
}

.project-card.featured {
    border: 3px solid var(--accent-color);
}

.featured-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: var(--gradient-secondary);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    z-index: 10;
}

.project-image {
    position: relative;
    height: 200px;
    overflow: hidden;
}

.project-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.project-card:hover .project-image img {
    transform: scale(1.1);
}

.project-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(59, 130, 246, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.project-card:hover .project-overlay {
    opacity: 1;
}

.project-link {
    width: 45px;
    height: 45px;
    background: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-color);
    text-decoration: none;
    transition: all 0.3s ease;
}

.project-link:hover {
    transform: scale(1.1);
}

.project-content {
    padding: 1.5rem;
}

.project-content h3 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-size: 1.2rem;
}

.project-content p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
}

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

.tag {
    background: var(--primary-color);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 15px;
    font-size: 0.8rem;
    font-weight: 500;
}

/* Experience Section */
.experience {
    padding: 5rem 0;
    background-color: var(--bg-primary);
}

.experience-content {
    max-width: 1000px;
    margin: 0 auto;
}

.experience-card {
    background: var(--bg-secondary);
    border-radius: 20px;
    padding: 2rem;
    box-shadow: var(--shadow-medium);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

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

.experience-card.current {
    border: 2px solid var(--primary-color);
    transform: translateY(-5px);
}

.experience-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-heavy);
}

.experience-header {
    display: flex;
    align-items: flex-start;
    gap: 2rem;
    margin-bottom: 2rem;
    position: relative;
}

.company-logo {
    background: var(--gradient-secondary);
    width: 80px;
    height: 80px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
    flex-shrink: 0;
    box-shadow: var(--shadow-medium);
}

.experience-info {
    flex: 1;
}

.experience-info h3 {
    color: var(--text-primary);
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.experience-info h4 {
    color: var(--primary-color);
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.experience-duration {
    color: var(--text-secondary);
    font-weight: 500;
    margin-bottom: 0.25rem;
}

.experience-type {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.current-badge {
    position: absolute;
    top: 0;
    right: 0;
    background: var(--gradient-primary);
    color: white;
    padding: 0.5rem 1.5rem;
    border-radius: 0 15px 0 15px;
    font-size: 0.8rem;
    font-weight: 600;
    box-shadow: var(--shadow-light);
}

.experience-description {
    margin-bottom: 2rem;
}

.experience-description p {
    color: var(--text-secondary);
    line-height: 1.7;
    font-size: 1.1rem;
}

.responsibilities {
    margin-bottom: 2rem;
}

.responsibilities h4 {
    color: var(--text-primary);
    font-size: 1.1rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.responsibilities h4 i {
    color: var(--primary-color);
}

.responsibilities ul {
    list-style: none;
    padding: 0;
}

.responsibilities li {
    color: var(--text-secondary);
    margin-bottom: 0.8rem;
    padding-left: 1.5rem;
    position: relative;
    line-height: 1.6;
}

.responsibilities li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: 600;
}

.tech-stack {
    margin-bottom: 2rem;
}

.tech-stack h4 {
    color: var(--text-primary);
    font-size: 1.1rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.tech-stack h4 i {
    color: var(--primary-color);
}

.tech-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tech-tag {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

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

.impact-section {
    margin-bottom: 1.5rem;
}

.impact-section h4 {
    color: var(--text-primary);
    font-size: 1.1rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.impact-section h4 i {
    color: var(--accent-color);
}

.impact-section p {
    color: var(--text-secondary);
    line-height: 1.6;
    font-style: italic;
    background: var(--bg-tertiary);
    padding: 1rem;
    border-radius: 10px;
    border-left: 4px solid var(--accent-color);
}

.contact-info {
    border-top: 1px solid var(--border-color);
    padding-top: 1.5rem;
    display: flex;
    gap: 2rem;
    flex-wrap: wrap;
}

.contact-info p {
    color: var(--text-secondary);
    margin: 0;
    font-size: 0.9rem;
}

.contact-info a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.contact-info a:hover {
    text-decoration: underline;
}

/* Research Section */
.research {
    padding: 5rem 0;
    background-color: var(--bg-secondary);
}

.research-content {
    max-width: 800px;
    margin: 0 auto;
}

.research-paper {
    background: var(--bg-primary);
    border-radius: 15px;
    padding: 2rem;
    box-shadow: var(--shadow-medium);
    display: flex;
    gap: 2rem;
    align-items: flex-start;
}

.paper-icon {
    background: var(--gradient-primary);
    width: 80px;
    height: 80px;
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
    flex-shrink: 0;
}

.paper-content h3 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-size: 1.3rem;
}

.paper-authors {
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
    font-weight: 500;
}

.paper-journal {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-weight: 500;
}

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

.paper-actions {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.paper-metrics {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.metric {
    color: var(--text-secondary);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Contact Section */
.whatsapp-contact {
    display: flex;
    justify-content: flex-start;
    margin-top: 30px;

}

.whatsapp-btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    background-color: #25D366; /* WhatsApp green */
    color: white;
    padding: 12px 24px;
    border: none;
    border-radius: 50px;
    font-size: 16px;
    text-decoration: none;
    font-weight: 600;
    transition: background-color 0.3s ease, transform 0.2s ease;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1);
}

.whatsapp-btn i {
    font-size: 20px;
}

.whatsapp-btn:hover {
    background-color: #1ebe5d;
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.15);
}
.contact {
    padding: 5rem 0;
    background-color: var(--bg-primary);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    max-width: 1000px;
    margin: 0 auto;
}

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

.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;
}

/* Google Form Section */
.google-form-section {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
}

.form-card {
    background: var(--bg-secondary);
    padding: 2.5rem;
    border-radius: 20px;
    box-shadow: var(--shadow-light);
    text-align: center;
    transition: all 0.3s ease;
    max-width: 400px;
    width: 100%;
    border: 2px solid transparent;
}

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

.form-header {
    margin-bottom: 2rem;
}

.form-header i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.form-header h3 {
    color: var(--text-primary);
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.form-header p {
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.5;
}

.google-form-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    background: linear-gradient(135deg, #4285f4, #34a853);
    color: white;
    padding: 1.2rem 2rem;
    border: none;
    border-radius: 50px;
    font-size: 1.1rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s ease;
    box-shadow: 0 8px 25px rgba(66, 133, 244, 0.3);
    position: relative;
    overflow: hidden;
    width: 100%;
    margin-bottom: 2rem;
}

.google-form-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: left 0.5s;
}

.google-form-btn:hover::before {
    left: 100%;
}

.google-form-btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 35px rgba(66, 133, 244, 0.4);
    background: linear-gradient(135deg, #3367d6, #2d8a47);
}

.google-form-btn i:first-child {
    font-size: 1.3rem;
}

.google-form-btn i:last-child {
    font-size: 0.9rem;
    opacity: 0.8;
}

.form-features {
    display: flex;
    justify-content: space-around;
    gap: 1rem;
    margin-top: 1.5rem;
}

.feature {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.feature i {
    font-size: 1.2rem;
    color: var(--primary-color);
    background: var(--bg-tertiary);
    padding: 0.5rem;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
}

.feature:hover i {
    background: var(--primary-color);
    color: white;
    transform: scale(1.1);
}

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

.footer-content p {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.footer-content i {
    color: #ef4444;
}

/* Responsive Design */
/* Tablet and small desktop screens */
@media (max-width: 1024px) {
    .container {
        padding: 0 1.5rem;
    }
    
    .hero-container {
        gap: 3rem;
    }
    
    .profile-img {
        width: 280px;
        height: 280px;
    }
    
    .projects-grid {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    }
    
    .skills-grid {
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    }
}

/* Mobile landscape and tablets */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: var(--bg-primary);
        flex-direction: column;
        justify-content: flex-start;
        align-items: center;
        padding-top: 2rem;
        transition: left 0.3s ease;
        box-shadow: var(--shadow-medium);
        z-index: 999;
    }

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

    .hamburger {
        display: flex;
    }
    
    .nav-link {
        padding: 1rem 0;
        font-size: 1.1rem;
        width: 100%;
        text-align: center;
    }
    
    .cv-btn {
        margin-top: 1rem;
        padding: 0.75rem 2rem;
    }
    
    .theme-toggle {
        margin-top: 1rem;
    }

    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
        padding: 2rem 1rem;
    }

    .hero-title {
        font-size: 2.5rem;
        line-height: 1.2;
    }
    
    .hero-subtitle {
        font-size: 1.3rem;
    }
    
    .hero-description {
        font-size: 1rem;
        margin-bottom: 1.5rem;
    }

    .hero-buttons {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
        width: 100%;
    }
    
    .btn {
        width: 100%;
        max-width: 300px;
        justify-content: center;
    }

    .profile-img {
        width: 250px;
        height: 250px;
    }

    .floating-icon {
        width: 45px;
        height: 45px;
        font-size: 1.2rem;
    }
    
    .section-title {
        font-size: 2rem;
        margin-bottom: 2rem;
    }
    
    .skills-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .skill-category {
        padding: 1.5rem;
    }

    .projects-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .projects-filter {
        flex-wrap: wrap;
        justify-content: center;
        gap: 0.5rem;
    }
    
    .filter-btn {
        flex: 1;
        min-width: 120px;
        max-width: 150px;
        text-align: center;
    }

    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .form-card {
        padding: 2rem;
        max-width: 100%;
    }
    
    .form-header h3 {
        font-size: 1.3rem;
    }
    
    .form-header p {
        font-size: 0.95rem;
    }
    
    .google-form-btn {
        padding: 1rem 1.5rem;
        font-size: 1rem;
    }
    
    .form-features {
        gap: 0.5rem;
    }
    
    .feature {
        font-size: 0.85rem;
    }
    
    .feature i {
        width: 35px;
        height: 35px;
        font-size: 1rem;
    }

    .experience {
        padding: 3rem 0;
    }

    .experience-card {
        padding: 2rem;
    }

    .experience-header {
        flex-direction: column;
        text-align: center;
        gap: 1.5rem;
    }

    .company-logo {
        margin: 0 auto;
        width: 70px;
        height: 70px;
        font-size: 1.5rem;
    }

    .current-badge {
        position: static;
        display: inline-block;
        margin: 0 auto 1rem;
        border-radius: 15px;
    }

    .tech-tags {
        justify-content: center;
    }

    .tech-tag {
        font-size: 0.8rem;
        padding: 0.4rem 0.8rem;
    }

    .contact-info {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }

    .research-paper {
        flex-direction: column;
        text-align: center;
        gap: 1.5rem;
    }
    
    .paper-icon {
        margin: 0 auto;
    }

    .paper-actions {
        justify-content: center;
        flex-wrap: wrap;
    }

    .paper-metrics {
        justify-content: center;
        gap: 1rem;
    }
    
    .about {
        padding: 3rem 0;
    }
    
    .projects {
        padding: 3rem 0;
    }
    
    .research {
        padding: 3rem 0;
    }
    
    .contact {
        padding: 3rem 0;
    }
}

/* Small mobile devices */
@media (max-width: 480px) {
    .container {
        padding: 0 1rem;
    }

    .nav-container {
        padding: 0 1rem;
    }
    
    .nav-logo h2 {
        font-size: 1.2rem;
    }
    
    .nav-logo span {
        font-size: 0.8rem;
    }

    .hero-title {
        font-size: 2rem;
        margin-bottom: 0.5rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
        margin-bottom: 1rem;
    }

    .hero-description {
        font-size: 0.95rem;
        margin-bottom: 1.5rem;
    }

    .section-title {
        font-size: 1.8rem;
        margin-bottom: 1.5rem;
    }
    
    .section-title::after {
        width: 60px;
        height: 3px;
    }

    .contact-form {
        padding: 1rem;
    }
    
    .form-group {
        margin-bottom: 1rem;
    }
    
    .form-group input,
    .form-group textarea {
        padding: 0.75rem;
        font-size: 0.95rem;
    }

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

    .project-card {
        margin: 0 auto;
        max-width: 100%;
    }
    
    .project-content {
        padding: 1rem;
    }
    
    .project-content h3 {
        font-size: 1.1rem;
    }
    
    .project-image {
        height: 180px;
    }

    .profile-img {
        width: 200px;
        height: 200px;
    }

    .floating-icon {
        width: 35px;
        height: 35px;
        font-size: 1rem;
    }

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

    .skill-category {
        padding: 1rem;
    }
    
    .skill-category h3 {
        font-size: 1rem;
        margin-bottom: 0.75rem;
    }

    .social-links {
        justify-content: center;
        gap: 0.75rem;
    }
    
    .social-link {
        width: 40px;
        height: 40px;
        font-size: 0.9rem;
    }

    .hero-buttons {
        gap: 0.75rem;
    }

    .btn {
        padding: 0.75rem 1.5rem;
        font-size: 0.9rem;
    }
    
    .filter-btn {
        padding: 0.5rem 1rem;
        font-size: 0.85rem;
        min-width: 100px;
    }

    .progress::after {
        display: none;
    }
    
    .research-paper {
        padding: 1.5rem;
    }
    
    .paper-icon {
        width: 60px;
        height: 60px;
        font-size: 1.5rem;
    }
    
    .paper-content h3 {
        font-size: 1.1rem;
    }
    
    .paper-actions {
        gap: 0.5rem;
    }
    
    .paper-actions .btn {
        padding: 0.5rem 1rem;
        font-size: 0.85rem;
    }
    
    .paper-metrics {
        gap: 0.75rem;
    }
    
    .metric {
        font-size: 0.8rem;
    }
    
    .contact-item {
        font-size: 0.9rem;
    }
    
    .form-card {
        padding: 1.5rem;
    }
    
    .form-header i {
        font-size: 2.5rem;
    }
    
    .form-header h3 {
        font-size: 1.2rem;
    }
    
    .form-header p {
        font-size: 0.9rem;
    }
    
    .google-form-btn {
        padding: 0.9rem 1.2rem;
        font-size: 0.95rem;
        gap: 0.8rem;
    }
    
    .google-form-btn i:first-child {
        font-size: 1.1rem;
    }
    
    .form-features {
        flex-direction: column;
        gap: 1rem;
    }
    
    .feature {
        flex-direction: row;
        font-size: 0.8rem;
        gap: 0.8rem;
    }
    
    .feature i {
        width: 30px;
        height: 30px;
        font-size: 0.9rem;
    }
    
    .footer {
        padding: 1.5rem 0;
    }
    
    .footer-content p {
        font-size: 0.85rem;
    }
}

/* Animation Classes */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    animation: fadeInUp 0.6s ease forwards;
}

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

.slide-in-left {
    opacity: 0;
    transform: translateX(-50px);
    animation: slideInLeft 0.6s ease forwards;
}

@keyframes slideInLeft {
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.slide-in-right {
    opacity: 0;
    transform: translateX(50px);
    animation: slideInRight 0.6s ease forwards;
}

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

/* Smooth transitions for theme switching */
* {
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

/* Touch-friendly improvements */
@media (hover: none) and (pointer: coarse) {
    .btn, .filter-btn, .social-link, .project-link {
        min-height: 44px;
        min-width: 44px;
    }
    
    .nav-link {
        padding: 1rem 0.5rem;
    }
    
    .form-group input,
    .form-group textarea {
        min-height: 44px;
    }
}

/* Prevent zoom on inputs for iOS */
@media screen and (-webkit-min-device-pixel-ratio: 0) {
    .form-group input,
    .form-group textarea {
        font-size: 16px;
    }
}

/* Better hamburger menu interaction */
.hamburger {
    padding: 10px;
    z-index: 1001;
    position: relative;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(-45deg) translate(-6px, 6px);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
}

.hamburger.active span:nth-child(3) {
    transform: rotate(45deg) translate(-6px, -6px);
}

/* Smooth scrolling for all browsers */
html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

/* High DPI display support */
@media only screen and (-webkit-min-device-pixel-ratio: 2),
only screen and (min--moz-device-pixel-ratio: 2),
only screen and (-o-min-device-pixel-ratio: 2/1),
only screen and (min-device-pixel-ratio: 2),
only screen and (min-resolution: 192dpi),
only screen and (min-resolution: 2dppx) {
    .profile-img {
        image-rendering: -webkit-optimize-contrast;
        image-rendering: crisp-edges;
    }
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--secondary-color);
}

/* Focus states for accessibility */
.btn:focus,
.nav-link:focus,
.social-link:focus,
.filter-btn:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

.form-group input:focus,
.form-group textarea:focus {
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

/* Additional mobile optimizations */
@media (max-width: 768px) {
    /* Prevent horizontal scroll */
    body {
        overflow-x: hidden;
    }
    
    /* Improve touch target sizes */
    .nav-link,
    .btn,
    .filter-btn,
    .social-link,
    .project-link {
        min-height: 44px;
        display: flex;
        align-items: center;
        justify-content: center;
    }
    
    /* Better mobile menu overlay */
    .nav-menu.active {
        backdrop-filter: blur(20px);
    }
    
    /* Improve readability on small screens */
    .project-content p,
    .about-text p,
    .hero-description,
    .paper-abstract {
        line-height: 1.7;
    }
    
    /* Better spacing for mobile */
    .hero {
        min-height: 90vh;
    }
    
    /* Optimize image sizes for mobile */
    .project-image img {
        object-fit: cover;
        width: 100%;
        height: 100%;
    }
}

/* Very small screens */
@media (max-width: 320px) {
    .hero-title {
        font-size: 1.8rem;
    }
    
    .hero-subtitle {
        font-size: 1.1rem;
    }
    
    .section-title {
        font-size: 1.6rem;
    }
    
    .container {
        padding: 0 0.75rem;
    }
    
    .nav-container {
        padding: 0 0.75rem;
    }
}

/* Landscape mobile devices */
@media (max-height: 500px) and (orientation: landscape) {
    .hero {
        min-height: 100vh;
        padding: 1rem 0;
    }
    
    .hero-container {
        gap: 1rem;
    }
    
    .profile-img {
        width: 180px;
        height: 180px;
    }
    
    .floating-icon {
        width: 30px;
        height: 30px;
        font-size: 0.9rem;
    }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --shadow-light: 0 2px 4px rgba(0, 0, 0, 0.3);
        --shadow-medium: 0 4px 8px rgba(0, 0, 0, 0.3);
        --shadow-heavy: 0 8px 16px rgba(0, 0, 0, 0.3);
    }
    
    .btn {
        border: 2px solid currentColor;
    }
}

/* Reduce motion for users who prefer it */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    .floating-icon {
        animation: none;
    }
    
    .profile-card {
        animation: none;
    }
}