/* Base Styles */
:root {
    /* Light Theme */
    --light-primary-color: #2563eb;
    --light-primary-dark: #1d4ed8;
    --light-secondary-color: #6b7280;
    --light-text-color: #1f2937;
    --light-bg-color: #f9fafb;
    --light-card-bg: #ffffff;
    --light-section-bg: #f3f4f6;
    --light-border-color: #e5e7eb;
    --light-nav-bg: rgba(255, 255, 255, 0.95);
    --light-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    --light-input-bg: #ffffff;
    
    /* Dark Theme */
    --dark-primary-color: #3b82f6;
    --dark-primary-dark: #2563eb;
    --dark-secondary-color: #9ca3af;
    --dark-text-color: #f3f4f6;
    --dark-bg-color: #0e1013;
    --dark-card-bg: #1f2937;
    --dark-section-bg: #1a202c;
    --dark-border-color: #374151;
    --dark-nav-bg: rgba(17, 24, 39, 0.95);
    --dark-shadow: 0 4px 12px rgba(0, 0, 0, 0.5);
    --dark-input-bg: #374151;
    
    /* Initial theme (will be overridden by JS) */
    --primary-color: var(--dark-primary-color);
    --primary-dark: var(--dark-primary-dark);
    --secondary-color: var(--dark-secondary-color);
    --text-color: var(--dark-text-color);
    --bg-color: var(--dark-bg-color);
    --card-bg: var(--dark-card-bg);
    --section-bg: var(--dark-section-bg);
    --border-color: var(--dark-border-color);
    --nav-bg: var(--dark-nav-bg);
    --shadow: var(--dark-shadow);
    --input-bg: var(--dark-input-bg);
    
    /* Other variables */
    --transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    --animation-curve: cubic-bezier(0.215, 0.61, 0.355, 1);
}

/* Theme transition */
body, section, header, footer, .card, input, textarea, button, 
.education-item, .skill-category, .project-card, 
.research-card, .timeline-content, .contact-form, 
.skill-list li::before, .hero {
    transition: background-color 0.5s ease, 
                color 0.5s ease, 
                border-color 0.5s ease,
                box-shadow 0.5s ease;
}

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Poppins', sans-serif;
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 1rem;
}

a {
    text-decoration: none;
    color: var(--primary-color);
    transition: var(--transition);
}

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

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
    position: relative;
    z-index: 2;
}

section {
    padding: 5rem 0;
    position: relative;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    text-align: center;
    position: relative;
    color: var(--primary-color);
}

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

.btn {
    display: inline-block;
    padding: 0.8rem 1.8rem;
    border-radius: 5px;
    font-weight: 500;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.btn:before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 0%;
    height: 100%;
    background-color: rgba(255, 255, 255, 0.1);
    transition: width 0.4s ease;
    z-index: -1;
}

.btn:hover:before {
    width: 100%;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
    box-shadow: 0 4px 6px rgba(37, 99, 235, 0.25);
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(37, 99, 235, 0.35);
}

.btn-secondary {
    background-color: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(37, 99, 235, 0.15);
}

/* Theme Toggler */
.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1001;
}

#theme-toggle-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: var(--card-bg);
    border: 2px solid var(--primary-color);
    color: var(--primary-color);
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

#theme-toggle-btn:hover {
    transform: rotate(30deg);
}

.dark-icon, .light-icon {
    position: absolute;
    transition: opacity 0.3s ease, transform 0.3s ease;
}

html.dark .dark-icon {
    opacity: 0;
    transform: scale(0);
}

html.dark .light-icon {
    opacity: 1;
    transform: scale(1);
}

html:not(.dark) .dark-icon {
    opacity: 1;
    transform: scale(1);
}

html:not(.dark) .light-icon {
    opacity: 0;
    transform: scale(0);
}

/* Header Styles */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: var(--nav-bg);
    box-shadow: var(--shadow);
    z-index: 1000;
    padding: 1rem 0;
    backdrop-filter: blur(10px);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo a {
    font-family: 'Poppins', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-color);
    position: relative;
    overflow: hidden;
    display: inline-block;
}

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

.logo a:hover::after {
    width: 100%;
}

.nav-links {
    display: flex;
    gap: 1.5rem;
}

.nav-links a {
    color: var(--text-color);
    font-weight: 500;
    position: relative;
    padding: 0.5rem 0;
}

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

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

.hamburger {
    display: none;
    cursor: pointer;
}

.bar {
    display: block;
    width: 25px;
    height: 3px;
    margin: 5px auto;
    transition: var(--transition);
    background-color: var(--text-color);
}

/* Hero Section */
#hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    background-color: var(--bg-color);
    padding-top: 80px;
    position: relative;
    overflow: hidden;
}

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

.hero-content {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 2rem;
    position: relative;
    z-index: 2;
}

.profile-image {
    flex: 0 0 250px;
    position: relative;
}

#profile-pic {
    width: 250px;
    height: 250px;
    object-fit: cover;
    border-radius: 50%;
    border: 5px solid var(--primary-color);
    box-shadow: 0 0 20px rgba(59, 130, 246, 0.5);
    transition: transform 0.5s var(--animation-curve);
}

.profile-image:hover #profile-pic {
    transform: scale(1.05);
}

.hero-text {
    flex: 1;
    min-width: 300px;
    text-align: left;
}

.hero-content h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    color: var(--text-color);
    position: relative;
}

/* Glitch effect */
/* .glitch-text {
    position: relative;
}

.glitch-text::before,
.glitch-text::after {
    content: attr(data-text);
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0.8;
}

.glitch-text::before {
    color: var(--primary-color);
    z-index: -1;
    animation: glitch-animation 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94) both infinite;
    animation-play-state: paused;
}

.glitch-text::after {
    color: var(--primary-dark);
    z-index: -2;
    animation: glitch-animation 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94) reverse both infinite;
    animation-play-state: paused;
}

.glitch-text:hover::before,
.glitch-text:hover::after {
    animation-play-state: running;
}

@keyframes glitch-animation {
    0% {
        transform: translate(0);
    }
    20% {
        transform: translate(-2px, 2px);
    }
    40% {
        transform: translate(-2px, -2px);
    }
    60% {
        transform: translate(2px, 2px);
    }
    80% {
        transform: translate(2px, -2px);
    }
    100% {
        transform: translate(0);
    }
} */

.hero-content h2 {
    font-size: 1.8rem;
    font-weight: 500;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
    opacity: 0;
    animation: fadeInUp 1s var(--animation-curve) forwards;
    animation-delay: 0.2s;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    color: var(--secondary-color);
    opacity: 0;
    animation: fadeInUp 1s var(--animation-curve) forwards;
    animation-delay: 0.4s;
}

.hero-cta {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    opacity: 0;
    animation: fadeInUp 1s var(--animation-curve) forwards;
    animation-delay: 0.6s;
}

.social-links {
    display: flex;
    gap: 1.5rem;
    font-size: 1.5rem;
    opacity: 0;
    animation: fadeInUp 1s var(--animation-curve) forwards;
    animation-delay: 0.8s;
}

.social-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: var(--card-bg);
    color: var(--primary-color);
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.social-icon:hover {
    color: var(--primary-color);
    transform: translateY(-5px) scale(1.1);
    box-shadow: 0 10px 20px rgba(59, 130, 246, 0.25);
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* About Section */
#about {
    background-color: var(--section-bg);
    position: relative;
    z-index: 1;
}

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

.about-text p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    line-height: 1.8;
}

.education-item {
    margin-bottom: 1.5rem;
    padding: 1.5rem;
    background-color: var(--card-bg);
    border-radius: 12px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    display: flex;
    gap: 1rem;
}

.education-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

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

.education-details {
    flex: 1;
}

.education-item h4 {
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

/* Experience Section */
#experience {
    background-color: var(--bg-color);
    position: relative;
}

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

.timeline::before {
    content: '';
    position: absolute;
    width: 4px;
    background-color: var(--primary-color);
    top: 0;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    border-radius: 2px;
}

.timeline-item {
    padding: 10px 40px;
    position: relative;
    width: 50%;
    box-sizing: border-box;
    margin-bottom: 50px;
}

.timeline-item:nth-child(odd) {
    left: 0;
}

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

.timeline-icon {
    position: absolute;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background-color: var(--primary-color);
    top: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    z-index: 1;
}

.timeline-item:nth-child(odd) .timeline-icon {
    right: -20px;
}

.timeline-item:nth-child(even) .timeline-icon {
    left: -20px;
}

.timeline-content {
    padding: 20px;
    background-color: var(--card-bg);
    border-radius: 12px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.timeline-content:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

.timeline-date {
    color: var(--primary-color);
    font-weight: 600;
    margin-bottom: 10px;
}

.timeline-content h3 {
    color: var(--text-color);
    margin-bottom: 5px;
}

.timeline-content h4 {
    color: var(--secondary-color);
    font-size: 0.9rem;
    margin-bottom: 15px;
}

.experience-details li {
    margin-bottom: 1rem;
    position: relative;
    padding-left: 1.5rem;
}

.experience-details li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

/* Research Section */
#research {
    background-color: var(--section-bg);
    position: relative;
}

.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.research-card {
    background-color: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    height: 100%;
    display: flex;
    flex-direction: column;
}

.research-card:hover {
    transform: translateY(-10px) rotateY(5deg);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
}

.research-img {
    height: 200px;
    overflow: hidden;
}

.placeholder-img {
    width: 100%;
    height: 100%;
    background-color: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: white;
}

.research-content {
    padding: 1.5rem;
    flex: 1;
}

.research-card h3 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.research-status {
    font-style: italic;
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
}

.research-place {
    color: var(--secondary-color);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.research-details li {
    margin-bottom: 0.8rem;
    position: relative;
    padding-left: 1.5rem;
}

.research-details li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

/* Projects Section */
#projects, #older-projects {
    background-color: var(--bg-color);
    position: relative;
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.project-card {
    background-color: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    height: 100%;
    display: flex;
    flex-direction: column;
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
}

.project-img {
    height: 200px;
    overflow: hidden;
}

.project-content {
    padding: 1.5rem;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.project-header {
    margin-bottom: 1rem;
}

.project-header h3 {
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.project-meta {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.project-duration, .project-advisor {
    color: var(--secondary-color);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.project-description {
    flex: 1;
    line-height: 1.8;
}

.project-description li {
    margin-bottom: 0.8rem;
    position: relative;
    padding-left: 1.5rem;
}

.project-description li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

/* Year section styles */
.year-section {
    margin-bottom: 4rem;
}

.year-section:last-child {
    margin-bottom: 0;
}

.year-heading {
    position: relative;
    text-align: center;
    margin-bottom: 2.5rem;
    color: var(--primary-color);
    font-size: 1.8rem;
}

.year-heading:before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    width: 100%;
    height: 1px;
    background-color: var(--border-color);
    z-index: 1;
}

.year-heading span {
    position: relative;
    z-index: 2;
    background-color: var(--bg-color);
    padding: 0 1.5rem;
    display: inline-block;
}

/* Skills Section */
#skills {
    background-color: var(--section-bg);
    position: relative;
}

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

.skill-category {
    background-color: var(--card-bg);
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.skill-category:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
}

.skill-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 1rem;
    background-color: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}

.skill-category h3 {
    color: var(--primary-color);
    margin-bottom: 1.5rem;
    text-align: center;
}

.skill-list li {
    position: relative;
    margin-bottom: 1rem;
    padding-left: 1.5rem;
  }
  
  .skill-list li::before {
    content: "→";
    position: absolute;
    left: 0;
    color: var(--primary-color);
  }
  
  .skill-list li::after {
    content: '';
    display: block;
    height: 6px;
    background: linear-gradient(90deg, var(--primary-color), var(--primary-dark));
    border-radius: 3px;
    margin-top: 5px;
    width: 0;                              /* start collapsed */
    transition: width 1s var(--animation-curve);
  }
  
  /* when JS sets --skill-width and adds .animated … */
  .skill-list li.animated::after {
    width: var(--skill-width);
  }


/* .skill-list li {
    margin-bottom: 1rem;
    position: relative;
    padding-left: 1.5rem;
}

.skill-list li:before {
    content: "→";
    position: absolute;
    left: 0;
    color: var(--primary-color);
}

.skill-list li::after {
    content: '';
    display: block;
    height: 6px;
    background-color: var(--primary-color);
    border-radius: 3px;
    margin-top: 5px;
    width: 0;
    /* transition: width 1s ease-in-out; 
} */

/* .skill-category:hover .skill-list li::after {
    width: calc(attr(data-skill) * 1%);
}

.skill-list li[data-skill="95"]::after { max-width: 95%; }
.skill-list li[data-skill="90"]::after { max-width: 90%; }
.skill-list li[data-skill="85"]::after { max-width: 85%; }
.skill-list li[data-skill="80"]::after { max-width: 80%; }
.skill-list li[data-skill="75"]::after { max-width: 75%; }
.skill-list li[data-skill="70"]::after { max-width: 70%; } */

/* Contact Section */
#contact {
    background-color: var(--bg-color);
    position: relative;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 3rem;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

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

.contact-item:hover {
    transform: translateX(10px);
}

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

.contact-item:hover i {
    transform: scale(1.1);
}

.contact-form {
    background-color: var(--card-bg);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

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

.form-group label {
    display: block;
    margin-bottom: 0.8rem;
    font-weight: 500;
    color: var(--text-color);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 0.8rem;
    background-color: var(--input-bg);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-family: inherit;
    font-size: 1rem;
    color: var(--text-color);
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.25);
}

/* Footer */
footer {
    background-color: var(--section-bg);
    color: var(--text-color);
    padding: 2rem 0;
    text-align: center;
    position: relative;
}

/* Scroll to top button */
#scroll-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    cursor: pointer;
    transition: var(--transition);
    opacity: 0;
    visibility: hidden;
    z-index: 999;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

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

#scroll-top:hover {
    background-color: var(--primary-dark);
    transform: translateY(-5px);
}

/* Animation classes for AOS */
.section-fade {
    opacity: 0;
    transform: translateY(50px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.section-fade.active {
    opacity: 1;
    transform: translateY(0);
}

/* AOS styles */
[data-aos="fade-up"] {
    transform: translateY(50px);
    opacity: 0;
    transition: transform 0.6s ease, opacity 0.6s ease;
}

[data-aos="fade-up"].aos-animate {
    transform: translateY(0);
    opacity: 1;
}

[data-aos="fade-right"] {
    transform: translateX(-50px);
    opacity: 0;
    transition: transform 0.6s ease, opacity 0.6s ease;
}

[data-aos="fade-right"].aos-animate {
    transform: translateX(0);
    opacity: 1;
}

[data-aos="fade-left"] {
    transform: translateX(50px);
    opacity: 0;
    transition: transform 0.6s ease, opacity 0.6s ease;
}

[data-aos="fade-left"].aos-animate {
    transform: translateX(0);
    opacity: 1;
}

[data-aos="zoom-in"] {
    transform: scale(0.5);
    opacity: 0;
    transition: transform 0.6s ease, opacity 0.6s ease;
}

[data-aos="zoom-in"].aos-animate {
    transform: scale(1);
    opacity: 1;
}

[data-aos="flip-left"] {
    transform: perspective(400px) rotateY(90deg);
    opacity: 0;
    transition: transform 0.6s ease, opacity 0.6s ease;
}

[data-aos="flip-left"].aos-animate {
    transform: perspective(400px) rotateY(0);
    opacity: 1;
}

[data-aos="flip-right"] {
    transform: perspective(400px) rotateY(-90deg);
    opacity: 0;
    transition: transform 0.6s ease, opacity 0.6s ease;
}

[data-aos="flip-right"].aos-animate {
    transform: perspective(400px) rotateY(0);
    opacity: 1;
}

[data-aos="flip-up"] {
    transform: perspective(400px) rotateX(90deg);
    opacity: 0;
    transition: transform 0.6s ease, opacity 0.6s ease;
}

[data-aos="flip-up"].aos-animate {
    transform: perspective(400px) rotateX(0);
    opacity: 1;
}

/* Media Queries */
@media (max-width: 992px) {
    .about-content,
    .contact-content {
        grid-template-columns: 1fr;
    }
    
    .hero-content h1 {
        font-size: 3rem;
    }
    
    .hero-content h2 {
        font-size: 1.5rem;
    }
    
    .timeline::before {
        left: 30px;
    }
    
    .timeline-item {
        width: 100%;
        padding-left: 70px;
        padding-right: 25px;
    }
    
    .timeline-item:nth-child(even) {
        left: 0;
    }
    
    .timeline-icon {
        left: 10px;
    }
    
    .timeline-item:nth-child(odd) .timeline-icon {
        right: auto;
        left: 10px;
    }
}

@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        left: -100%;
        top: 5rem;
        flex-direction: column;
        background-color: var(--card-bg);
        width: 100%;
        border-radius: 10px;
        text-align: center;
        transition: var(--transition);
        box-shadow: var(--shadow);
        padding: 2rem;
    }
    
    .nav-links.active {
        left: 0;
    }
    
    .hamburger {
        display: block;
    }
    
    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }
    
    .hamburger.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }
    
    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }
    
    .section-title {
        font-size: 1.8rem;
    }
    
    .hero-content h1 {
        font-size: 2.5rem;
    }
    
    .hero-content h2 {
        font-size: 1.3rem;
    }
    
    .hero-content {
        text-align: center;
    }
    
    .hero-text {
        text-align: center;
    }
    
    .hero-cta {
        flex-direction: column;
        gap: 1rem;
        align-items: center;
    }
    
    .social-links {
        justify-content: center;
    }
    
    .btn {
        width: 100%;
    }
}

@media (max-width: 576px) {
    .skills-container,
    .experience-grid,
    .research-grid,
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .hero-content h2 {
        font-size: 1.1rem;
    }
    
    .contact-item {
        flex-direction: column;
        text-align: center;
    }
}