:root {
    --primary-color: #007bff;
    --secondary-color: #343a40;
    --background-color: #f8f9fa;
    --card-background: #ffffff;
    --text-color: #212529;
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

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

body {
    font-family: var(--font-family);
    line-height: 1.6;
    background-color: var(--background-color);
    color: var(--text-color);
    scroll-behavior: smooth;
}

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

.section-padding {
    padding: 80px 0;
}

h1, h2, h3 {
    color: var(--secondary-color);
    margin-bottom: 20px;
}

h2 {
    font-size: 2.5em;
    text-align: center;
    margin-bottom: 40px;
}

.btn {
    display: inline-block;
    padding: 10px 25px;
    margin: 10px 10px 10px 0;
    border: 2px solid transparent;
    border-radius: 5px;
    cursor: pointer;
    text-decoration: none;
    font-weight: 600;
    transition: background-color 0.3s, color 0.3s, transform 0.3s, border-color 0.3s;
}

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

.primary-btn:hover {
    background-color: #0056b3;
    transform: translateY(-2px);
}

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

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

header {
    background-color: var(--card-background);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
}

.logo {
    font-size: 1.5em;
    color: var(--primary-color);
}

.nav-menu a {
    color: var(--secondary-color);
    text-decoration: none;
    margin-left: 25px;
    font-weight: 500;
    transition: color 0.3s;
}

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

.nav-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5em;
    cursor: pointer;
    color: var(--secondary-color);
}

.hero-section {
    background: linear-gradient(135deg, #e0f7fa 0%, var(--background-color) 100%);
    min-height: 80vh;
    display: flex;
    align-items: center;
}

.hero-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 40px;
    padding: 60px 20px;
}

.hero-text h1 {
    font-size: 4em;
    color: var(--primary-color);
    margin: 0;
}

.hero-text h2 {
    font-size: 1.8em;
    font-weight: 300;
    margin-top: 5px;
    color: var(--secondary-color);
}

.hero-text .intro-line {
    font-size: 1.2em;
    color: #6c757d;
    font-weight: 500;
}

.hero-image img {
    max-width: 300px;
    height: auto;
    border-radius: 50%;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.15);
}

.about-section h2 i {
    color: var(--primary-color);
}

.about-grid {
    max-width: 800px;
    margin: 0 auto;
}

.bio p {
    margin-bottom: 15px;
    text-align: center;
}

.education-section {
    background-color: var(--card-background);
}

.education-section h2 i {
    color: var(--primary-color);
}

.education-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 30px;
}

.education-card {
    background-color: #f1f1f1;
    padding: 30px;
    border-radius: 8px;
    border-left: 5px solid var(--primary-color);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

.education-card h3 {
    color: var(--primary-color);
    margin-bottom: 5px;
}

.education-card .institution {
    font-weight: 600;
    margin-bottom: 5px;
}

.education-card .duration {
    color: #6c757d;
    font-size: 0.9em;
    margin-bottom: 10px;
}

.skills-section {
    background-color: var(--background-color);
}

.skills-section h2 i {
    color: var(--primary-color);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    text-align: center;
}

.skill-category {
    padding: 20px;
    border-left: 3px solid var(--primary-color);
    background-color: var(--card-background);
    border-radius: 5px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.05);
    transition: box-shadow 0.3s;
}

.skill-category:hover {
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

.skill-category h3 {
    font-size: 1.3em;
    margin-bottom: 15px;
    color: var(--secondary-color);
}

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

.skill-category li {
    padding: 5px 0;
    font-size: 1em;
}

.projects-section {
    background-color: #e0f7fa;
}

.projects-section h2 i {
    color: var(--primary-color);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.project-card {
    background-color: var(--card-background);
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, box-shadow 0.3s;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
}

.project-card h3 {
    color: var(--primary-color);
    margin-top: 0;
    margin-bottom: 10px;
}

.tech-stack {
    margin: 15px 0;
}

.tech-stack span {
    display: inline-block;
    background-color: #e9ecef;
    color: var(--secondary-color);
    padding: 5px 10px;
    border-radius: 3px;
    font-size: 0.85em;
    margin-right: 5px;
    margin-bottom: 5px;
}

.project-links {
    margin-top: 15px;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.project-links .btn {
    margin: 0;
}

.contact-section {
    background-color: var(--card-background);
    text-align: center;
}

.contact-section h2 i {
    color: var(--primary-color);
}

.contact-intro {
    max-width: 600px;
    margin: 0 auto 40px;
    font-size: 1.1em;
}

.contact-info-grid {
    display: flex;
    justify-content: center;
    gap: 30px;
    flex-wrap: wrap;
}

.contact-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 30px;
    border-radius: 8px;
    text-decoration: none;
    color: var(--text-color);
    background-color: #f1f1f1;
    width: 280px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, background-color 0.3s, color 0.3s;
}

.contact-card:hover {
    transform: translateY(-5px);
    background-color: var(--primary-color);
    color: white;
}

.contact-card:hover i {
    color: white;
}

.contact-card i {
    font-size: 3em;
    color: var(--primary-color);
    margin-bottom: 15px;
    transition: color 0.3s;
}

.contact-card h3 {
    margin: 0 0 5px 0;
    color: inherit;
}

.contact-card p {
    font-size: 0.9em;
    margin: 0;
}

footer {
    background-color: var(--secondary-color);
    color: white;
    text-align: center;
    padding: 20px 0;
    font-size: 0.9em;
}

@media (max-width: 768px) {
    
    .nav-toggle {
        display: block;
    }

    .nav-menu {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 60px;
        left: 0;
        width: 100%;
        background-color: var(--card-background);
        box-shadow: 0 4px 4px rgba(0, 0, 0, 0.1);
        padding: 10px 0;
    }

    .nav-menu a {
        margin: 5px 20px;
        padding: 10px 0;
        border-bottom: 1px solid #eee;
        text-align: center;
    }

    .nav-menu-visible {
        display: flex;
    }

    /* Hero Section adjustments for mobile */
    .hero-content {
        flex-direction: column-reverse;
        text-align: center;
        padding: 40px 20px;
    }

    .hero-text h1 {
        font-size: 3em;
    }

    .hero-image img {
        max-width: 200px;
        margin-bottom: 20px;
    }

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

    .btn {
        width: 80%;
    }

    h2 {
        font-size: 2em;
    }

    .projects-grid, .skills-grid, .education-grid, .contact-info-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-card {
        width: 100%;
        max-width: 400px;
    }
}