:root {
    --primary-color: #0d6efd;
    --primary-dark: #0b5ed7;
    --bg-color: #f8f9fa;
    --surface-color: #ffffff;
    --text-color: #212529;
    --text-secondary-color: #6c757d;
    --border-color: #dee2e6;
    --shadow-color: rgba(0, 0, 0, 0.05);
    --shadow-color-hover: rgba(0, 0, 0, 0.1);
    --font-family-sans-serif: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family-sans-serif);
    line-height: 1.7;
    color: var(--text-color);
    background-color: var(--bg-color);
    font-size: 1.1rem;
}

.container {
    max-width: 1140px;
    margin-left: auto;
    margin-right: auto;
    padding-left: 20px;
    padding-right: 20px;
}

/* Navigation */
.navbar {
    background-color: var(--surface-color);
    box-shadow: 0 2px 4px var(--shadow-color);
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1030;
    padding: 1.5rem 0;
    transition: padding 0.3s ease;
}

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

.logo {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 3rem;
    align-items: center;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    position: relative;
    padding-bottom: 0.5rem;
    transition: color 0.3s ease;
}

.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,
.nav-links a.active {
    color: var(--primary-color);
}

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

.cta-button {
    background-color: var(--primary-color);
    color: var(--surface-color) !important;
    padding: 1rem 2.5rem;
    border-radius: 50px;
    transition: background-color 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease;
    border: 2px solid transparent;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.cta-button:hover {
    background-color: var(--primary-dark);
    color: var(--surface-color) !important;
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

.cta-button.secondary {
    background: transparent;
    color: var(--primary-color) !important;
    border: 2px solid var(--primary-color);
}

.cta-button.secondary:hover {
    background: var(--primary-color);
    color: var(--surface-color) !important;
}


/* Hero Section */
#hero {
    padding: 14rem 0 10rem 0;
    background: var(--surface-color);
    text-align: center;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
    animation: fadeInUp 1s ease-out;
}

.hero-avatar {
    width: 180px;
    height: 180px;
    border-radius: 50%;
    margin: 0 auto 2.5rem auto;
    background: linear-gradient(145deg, var(--primary-color), #90baff);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 5rem;
    color: var(--surface-color);
    box-shadow: 0 10px 30px rgba(13, 110, 253, 0.3);
    font-weight: 600;
}

h1 {
    font-size: 4rem;
    margin-bottom: 1.5rem;
    line-height: 1.2;
    font-weight: 700;
}

.highlight {
    color: var(--primary-color);
}

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

.hero-description {
    font-size: 1.1rem;
    color: var(--text-secondary-color);
    margin-bottom: 3rem;
}

.hero-buttons {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
}

/* Sections */
section {
    padding: 8rem 0;
}

#about, #skills, #projects {
    background-color: var(--bg-color);
}

#experience, #education, #contact {
    background-color: var(--surface-color);
}

.section-title {
    text-align: center;
    margin-bottom: 5rem;
    font-size: 3rem;
    font-weight: 700;
    position: relative;
    padding-bottom: 1.5rem;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: var(--primary-color);
    border-radius: 2px;
}

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

.timeline::after {
    content: '';
    position: absolute;
    width: 4px;
    background-color: var(--primary-color);
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -2px;
    opacity: 0.2;
}

.experience-item {
    padding: 20px 40px;
    position: relative;
    background-color: inherit;
    width: 50%;
}

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

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

.experience-item::after {
    content: '';
    position: absolute;
    width: 24px;
    height: 24px;
    right: -12px;
    background-color: white;
    border: 4px solid var(--primary-color);
    top: 28px;
    border-radius: 50%;
    z-index: 1;
}

.experience-item:nth-child(even)::after {
    left: -12px;
}

.experience-content {
    padding: 30px;
    background-color: var(--surface-color);
    position: relative;
    border-radius: 8px;
    box-shadow: 0 4px 15px var(--shadow-color);
    border: 1px solid var(--border-color);
}

.job-title {
    font-size: 1.75rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.company {
    font-weight: 500;
    margin-bottom: 0.75rem;
    display: block;
    color: var(--text-color);
}

.date {
    color: var(--text-secondary-color);
    font-size: 1rem;
    margin-bottom: 1.5rem;
    display: block;
}

.job-description {
    list-style: none;
    padding-left: 0;
}

.job-description li {
    margin-bottom: 0.75rem;
    position: relative;
    padding-left: 2rem;
}

.job-description li::before {
    content: '▹';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

/* Skills Section */
.skills-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2.5rem;
}

.skill-category {
    background: var(--surface-color);
    padding: 2.5rem;
    border-radius: 8px;
    box-shadow: 0 4px 15px var(--shadow-color);
    border: 1px solid var(--border-color);
}

.skill-category h3 {
    margin-bottom: 2rem;
    color: var(--primary-color);
    font-size: 1.5rem;
    font-weight: 600;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 1rem;
}

.skills-list {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
}

.skill-tag {
    background: var(--bg-color);
    padding: 0.75rem 1.25rem;
    border-radius: 5px;
    font-size: 1rem;
    color: var(--text-secondary-color);
    border: 1px solid var(--border-color);
    font-weight: 500;
}

/* Education Section */
.education-item {
    background: var(--surface-color);
    border-radius: 8px;
    padding: 2.5rem;
    margin-bottom: 2.5rem;
    box-shadow: 0 4px 15px var(--shadow-color);
    border: 1px solid var(--border-color);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.degree {
    font-size: 1.75rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.institution {
    font-weight: 500;
    margin-bottom: 0.75rem;
    display: block;
}

/* Projects Section */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2.5rem;
}

.project-card {
    background: var(--surface-color);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 10px 20px var(--shadow-color);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    flex-direction: column;
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px var(--shadow-color-hover);
}

.project-image {
    height: 220px;
    background: linear-gradient(145deg, var(--primary-color), #90baff);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--surface-color);
    font-size: 4.5rem;
}

.project-content {
    padding: 2rem;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}

.project-content h3 {
    margin-bottom: 1rem;
    color: var(--text-color);
    font-size: 1.5rem;
    font-weight: 600;
}

.project-content p {
    color: var(--text-secondary-color);
    margin-bottom: 1.5rem;
    line-height: 1.7;
    flex-grow: 1;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 2rem;
}

.project-tags span {
    background: var(--bg-color);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    color: var(--text-secondary-color);
    border: 1px solid var(--border-color);
}

.btn-link {
    display: inline-flex;
    align-items: center;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.3s ease;
    align-self: flex-start;
}

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

.btn-link i {
    margin-left: 0.75rem;
    transition: transform 0.3s ease;
}

.btn-link:hover i {
    transform: translateX(5px);
}

/* Contact Section */
.contact-container {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 5rem;
    align-items: center;
}

.contact-info h3 {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    color: var(--text-color);
    font-weight: 700;
}

.contact-info p {
    color: var(--text-secondary-color);
    margin-bottom: 2.5rem;
    line-height: 1.8;
}

.contact-item {
    display: flex;
    align-items: center;
    margin-bottom: 2rem;
    gap: 1.5rem;
}

.contact-item i {
    font-size: 1.5rem;
    color: var(--primary-color);
    width: 48px;
    height: 48px;
    background-color: var(--bg-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.contact-item h4 {
    font-size: 1.25rem;
    color: var(--text-color);
    margin-bottom: 0.25rem;
    font-weight: 600;
}

.contact-item a, .contact-item p {
    color: var(--text-secondary-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

.contact-item a:hover {
    color: var(--primary-color);
}

.social-links {
    display: flex;
    gap: 1.5rem;
    margin-top: 2.5rem;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--surface-color);
    color: var(--text-secondary-color);
    font-size: 1.5rem;
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

.social-links a:hover {
    background: var(--primary-color);
    color: var(--surface-color);
    transform: translateY(-3px);
    border-color: var(--primary-color);
}

/* Contact Form */
.contact-form {
    background: var(--surface-color);
    padding: 3rem;
    border-radius: 10px;
    box-shadow: 0 10px 30px var(--shadow-color-hover);
    border: 1px solid var(--border-color);
}

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

.form-group label {
    display: block;
    margin-bottom: 0.75rem;
    font-weight: 500;
    color: var(--text-color);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 1rem 1.25rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-family: var(--font-family-sans-serif);
    font-size: 1.1rem;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(13, 110, 253, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 150px;
}

.btn {
    display: inline-block;
    padding: 1rem 2.5rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    border: 1px solid transparent;
    cursor: pointer;
    font-size: 1.1rem;
}

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

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

/* Footer */
footer {
    background: var(--text-color);
    color: #adb5bd;
    padding: 4rem 0;
    text-align: center;
}

.footer-content {
    max-width: 600px;
    margin: 0 auto;
}

.footer-logo {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--surface-color);
    margin-bottom: 1.5rem;
}

.footer-text {
    margin-bottom: 2rem;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.footer-links a {
    color: #adb5bd;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: var(--surface-color);
}

.footer-links span {
    color: #6c757d;
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    background: var(--primary-color);
    color: var(--surface-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 999;
    box-shadow: 0 4px 12px var(--shadow-color-hover);
    text-decoration: none;
}

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

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

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

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

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

/* Hamburger Menu */
.hamburger {
    display: none;
    cursor: pointer;
}

.bar {
    display: block;
    width: 25px;
    height: 3px;
    margin: 5px auto;
    transition: all 0.3s ease-in-out;
    background-color: var(--text-color);
}

/* Responsive Design */
@media (max-width: 992px) {
    .nav-links {
        position: fixed;
        left: -100%;
        top: 70px; /* Adjust based on navbar height */
        flex-direction: column;
        background-color: var(--surface-color);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 2rem 0;
        gap: 1.5rem;
    }

    .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);
    }

    .contact-container {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .timeline::after {
        left: 31px;
    }

    .experience-item {
        width: 100%;
        padding-left: 70px;
        padding-right: 25px;
    }

    .experience-item:nth-child(even) {
        left: 0%;
    }

    .experience-item::after {
        left: 21px;
    }
}

@media (max-width: 768px) {
    h1 {
        font-size: 3rem;
    }

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

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

@media (max-width: 576px) {
    body {
        font-size: 1rem;
    }

    h1 {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.25rem;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .section-title {
        font-size: 2.25rem;
    }

    .contact-form {
        padding: 2.5rem;
    }
}