:root {
    /* Light theme colors */
    --bg-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --card-bg: rgba(255, 255, 255, 0.95);
    --text-primary: #333;
    --text-secondary: #2c3e50;
    --text-accent: #3498db;
    --text-muted: #7f8c8d;
    --border-color: #3498db;
    --shadow: rgba(0, 0, 0, 0.1);
    --shadow-hover: rgba(0, 0, 0, 0.15);
    --footer-bg: rgba(44, 62, 80, 0.95);
    --footer-text: white;
}

[data-theme="dark"] {
    /* Dark theme colors */
    --bg-gradient: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    --card-bg: rgba(30, 30, 46, 0.95);
    --text-primary: #e0e6ed;
    --text-secondary: #f8f9fa;
    --text-accent: #74b9ff;
    --text-muted: #a0a0a0;
    --border-color: #74b9ff;
    --shadow: rgba(0, 0, 0, 0.3);
    --shadow-hover: rgba(0, 0, 0, 0.4);
    --footer-bg: rgba(20, 20, 30, 0.95);
    --footer-text: #e0e6ed;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-gradient);
    min-height: 100vh;
    transition: all 0.3s ease;
}

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

.header {
    background: var(--card-bg);
    border-radius: 15px;
    padding: 40px;
    margin-bottom: 30px;
    box-shadow: 0 10px 30px var(--shadow);
    backdrop-filter: blur(10px);
    position: relative;
    transition: all 0.3s ease;
}

.theme-toggle {
    position: absolute;
    top: 20px;
    right: 20px;
}

.theme-toggle-btn {
    background: var(--text-accent);
    border: none;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    color: white;
    font-size: 1.2rem;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px var(--shadow);
}

.theme-toggle-btn:hover {
    transform: scale(1.1);
    box-shadow: 0 6px 16px var(--shadow-hover);
}

.theme-toggle-btn:active {
    transform: scale(0.95);
}

.profile {
    text-align: center;
}

.profile h1 {
    font-size: 3rem;
    color: var(--text-secondary);
    margin-bottom: 10px;
    font-weight: 700;
}

.profile h2 {
    font-size: 1.5rem;
    color: var(--text-accent);
    margin-bottom: 15px;
    font-weight: 400;
}

.location {
    color: var(--text-muted);
    font-size: 1.1rem;
}

.location i {
    margin-right: 8px;
    color: #e74c3c;
}

.main-content {
    display: grid;
    grid-template-columns: 1fr;
    gap: 25px;
}

.section {
    background: var(--card-bg);
    border-radius: 15px;
    padding: 30px;
    box-shadow: 0 8px 25px var(--shadow);
    backdrop-filter: blur(10px);
    transition: transform 0.3s ease, box-shadow 0.3s ease, background 0.3s ease;
}

.section:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px var(--shadow-hover);
}

.section h3 {
    color: var(--text-secondary);
    font-size: 1.8rem;
    margin-bottom: 20px;
    border-bottom: 3px solid var(--border-color);
    padding-bottom: 10px;
}

.section h3 i {
    margin-right: 10px;
    color: var(--text-accent);
}

.education-item h4 {
    color: var(--text-secondary);
    font-size: 1.3rem;
    margin-bottom: 8px;
}

.degree {
    color: var(--text-accent);
    font-weight: 600;
    margin-bottom: 5px;
}

.specialization {
    color: var(--text-muted);
    font-style: italic;
}

.project {
    margin-bottom: 25px;
    padding: 20px;
    border-left: 4px solid var(--text-accent);
    background: rgba(52, 152, 219, 0.05);
    border-radius: 8px;
    transition: all 0.3s ease;
}

[data-theme="dark"] .project {
    background: rgba(116, 185, 255, 0.1);
}

.project:last-child {
    margin-bottom: 0;
}

.project h4 {
    color: var(--text-secondary);
    font-size: 1.3rem;
    margin-bottom: 12px;
}

.project p {
    color: var(--text-primary);
    margin-bottom: 15px;
    line-height: 1.7;
}

.tech-stack {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.tech {
    background: var(--text-accent);
    color: white;
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 25px;
}

.skill-category h4 {
    color: var(--text-secondary);
    font-size: 1.2rem;
    margin-bottom: 12px;
    padding-bottom: 8px;
    border-bottom: 2px solid var(--border-color);
}

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

.skill-category li {
    color: var(--text-primary);
    margin-bottom: 8px;
    padding-left: 20px;
    position: relative;
}

.skill-category li::before {
    content: "▶";
    color: var(--text-accent);
    position: absolute;
    left: 0;
}

.cert-list {
    display: grid;
    gap: 15px;
}

.cert-item {
    padding: 15px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    transition: border-color 0.3s ease;
}

.cert-item:hover {
    border-color: var(--text-accent);
}

.cert-item h4 {
    color: var(--text-secondary);
    margin-bottom: 5px;
}

.cert-year {
    color: var(--text-accent);
    font-weight: 600;
}

.interests {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.interest {
    background: linear-gradient(45deg, var(--text-accent), #2980b9);
    color: white;
    padding: 10px 18px;
    border-radius: 25px;
    font-weight: 500;
    transition: transform 0.3s ease;
}

[data-theme="dark"] .interest {
    background: linear-gradient(45deg, #74b9ff, #0984e3);
}

.interest:hover {
    transform: scale(1.05);
}

/* Contact links styles */
.contact-links {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.contact-link {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 12px 20px;
    background: linear-gradient(135deg, var(--text-accent), #6c5ce7);
    color: white;
    text-decoration: none;
    border-radius: 10px;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px var(--shadow);
}

.contact-link:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px var(--shadow-hover);
    background: linear-gradient(135deg, #6c5ce7, var(--text-accent));
}

.contact-link i {
    font-size: 1.2rem;
}

.footer {
    background: var(--footer-bg);
    color: var(--footer-text);
    border-radius: 15px;
    padding: 25px;
    margin-top: 30px;
    text-align: center;
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.footer-content p {
    margin-bottom: 10px;
}

.footer-content a {
    color: var(--footer-text);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-content a:hover {
    color: var(--text-accent);
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    .header {
        padding: 25px;
    }
    
    .theme-toggle {
        top: 15px;
        right: 15px;
    }
    
    .theme-toggle-btn {
        width: 45px;
        height: 45px;
        font-size: 1.1rem;
    }
    
    .profile h1 {
        font-size: 2.2rem;
    }
    
    .profile h2 {
        font-size: 1.2rem;
    }
    
    .section {
        padding: 20px;
    }
    
    .skills-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-links {
        align-items: center;
    }
}

@media (max-width: 480px) {
    .profile h1 {
        font-size: 1.8rem;
    }
    
    .tech-stack {
        justify-content: center;
    }
    
    .interests {
        justify-content: center;
    }
    
    .theme-toggle-btn {
        width: 40px;
        height: 40px;
        font-size: 1rem;
    }
}