:root {
    --primary-color: #2563eb;
    --secondary-color: #0f172a;
    --text-color: #334155;
    --bg-color: #ffffff;
    --bg-alt-color: #f8fafc;
    --border-color: #e2e8f0;
    --max-width: 1200px;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* Header and Navigation */
header {
    position: sticky;
    top: 0;
    background-color: var(--bg-color);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    backdrop-filter: blur(10px);
    background-color: rgba(255, 255, 255, 0.95);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--secondary-color);
}

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

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s ease;
}

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

/* Hero Section */
.hero {
    padding: 5rem 0;
    text-align: center;
    background: linear-gradient(135deg, var(--bg-alt-color) 0%, var(--bg-color) 100%);
}

.hero-title {
    font-size: 3rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 1rem;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-color);
    margin-bottom: 2rem;
}

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

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    text-decoration: none;
    border-radius: 0.5rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

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

.btn-primary:hover {
    background-color: #1d4ed8;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

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

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

/* Sections */
.section {
    padding: 4rem 0;
}

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

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--secondary-color);
    margin-bottom: 2rem;
    text-align: center;
}

.lead {
    font-size: 1.125rem;
    line-height: 1.8;
    max-width: 800px;
    margin: 0 auto;
}

/* Experience Section */
.experience-item {
    margin-bottom: 3rem;
    padding: 2rem;
    background-color: var(--bg-color);
    border-radius: 0.5rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.section-alt .experience-item {
    background-color: white;
}

.experience-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.experience-header h3 {
    font-size: 1.5rem;
    color: var(--secondary-color);
}

.date {
    color: var(--text-color);
    font-weight: 500;
}

.company {
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 0.5rem;
}

.tech-stack {
    font-style: italic;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.experience-list {
    list-style-position: inside;
    line-height: 1.8;
}

.experience-list li {
    margin-bottom: 0.5rem;
}

/* Education Section */
.education-item {
    margin-bottom: 2rem;
    padding: 1.5rem;
    border-left: 4px solid var(--primary-color);
}

.education-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.education-header h3 {
    font-size: 1.25rem;
    color: var(--secondary-color);
}

.degree {
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.location, .description {
    color: var(--text-color);
}

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

.skill-category h3 {
    font-size: 1.25rem;
    color: var(--secondary-color);
    margin-bottom: 1rem;
}

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

.skill-tag {
    background-color: var(--primary-color);
    color: white;
    padding: 0.375rem 0.75rem;
    border-radius: 0.375rem;
    font-size: 0.875rem;
    font-weight: 500;
}

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

.achievement-item {
    padding: 1.5rem;
    background-color: var(--bg-alt-color);
    border-radius: 0.5rem;
    border-left: 4px solid var(--primary-color);
}

.achievement-item h3 {
    font-size: 1.125rem;
    color: var(--secondary-color);
    margin-bottom: 0.5rem;
}

.achievement-item p {
    color: var(--text-color);
}

/* Contact Section */
.contact-info {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.contact-info p {
    font-size: 1.125rem;
    margin-bottom: 2rem;
}

/* Footer */
footer {
    background-color: var(--secondary-color);
    color: white;
    padding: 2rem 0;
    text-align: center;
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .hero-links {
        flex-direction: column;
        align-items: center;
    }
    
    .section {
        padding: 3rem 0;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .experience-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .date {
        font-size: 0.875rem;
        margin-top: 0.25rem;
    }
    
    .skills-grid,
    .achievements-grid {
        grid-template-columns: 1fr;
    }
    
    .education-header {
        flex-direction: column;
        align-items: flex-start;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 3rem 0;
    }
    
    .hero-title {
        font-size: 1.75rem;
    }
    
    .experience-item {
        padding: 1.5rem;
    }
    
    .btn {
        width: 100%;
        text-align: center;
    }
}