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

:root {
    --primary: #3b7ab9;
    --primary-dark: #1f5183;
    --primary-light: #8fc2f5;
    --text: #1f2937;
    --text-light: #6b7280;
    --bg: #ffffff;
    --bg-alt: #f9fafb;
    --border: #e5e7eb;
}

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

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

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

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

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

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

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

/* Hero Section */
.hero {
    padding: 6rem 0;
    text-align: center;
    background: #1e293b;
    color: black;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.95;
}

.hero-photo {
    width: 200px;
    height: 200px;
    border-radius: 50%;
    object-fit: cover;
    margin: 0 auto 1.5rem;
    border: 8px solid var(--primary-light);
    box-shadow: 0 8px 20px rgba(0,0,0,0.3), inset 0 0 10px rgba(0,0,0,0.1);
}

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

.btn {
    padding: 0.75rem 2rem;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    display: inline-block;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.btn-secondary {
    background: rgba(255,255,255,0.2);
    color: white;
    border: 2px solid white;
}

.btn-secondary:hover {
    background: rgba(255,255,255,0.3);
}

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

section:nth-child(even) {
    background: var(--bg-alt);
}

.section-title {
    font-size: 2rem;
    margin-bottom: 3rem;
    text-align: center;
    font-weight: 700;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: var(--primary);
    margin: 1rem auto 0;
    border-radius: 2px;
}

/* About */
.about-content {
    max-width: 900px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
    background: white;
    padding: 2.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.about-content p {
    margin-bottom: 0;
    font-size: 1.05rem;
    line-height: 1.8;
    color: var(--text-light);
}

/* Education & Experience */
.timeline-item {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
    border-left: 4px solid var(--primary);
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.timeline-item h3 {
    font-size: 1.4rem;
    margin-bottom: 0.5rem;
    color: var(--text);
}

.timeline-meta {
    color: var(--text-light);
    font-size: 0.95rem;
    margin-bottom: 1rem;
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.timeline-meta span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.timeline-item ul {
    margin-left: 1.5rem;
    color: var(--text-light);
}

.timeline-item li {
    margin-bottom: 0.5rem;
}

/* Skills */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.skill-category {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

.skill-category h3 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: var(--primary);
}

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

.skill-category li {
    padding: 0.5rem 0;
    color: var(--text-light);
    border-bottom: 1px solid var(--border);
}

.skill-category li:last-child {
    border-bottom: none;
}

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

.project-card {
    background: white;
    border-radius: 8px;
    padding: 2rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    transition: transform 0.3s, box-shadow 0.3s;
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 16px rgba(0,0,0,0.12);
}

.project-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
    color: var(--text);
}

.project-date {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.project-card p {
    color: var(--text-light);
    line-height: 1.6;
}

/* Contact */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    max-width: 800px;
    margin: 0 auto;
}

.contact-item {
    text-align: center;
    padding: 2rem;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    transition: transform 0.3s;
}

.contact-item:hover {
    transform: translateY(-5px);
}

.contact-icon {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.contact-item h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    color: var(--text);
}

.contact-item a {
    color: var(--primary);
    text-decoration: none;
    word-break: break-all;
}

.contact-item a:hover {
    text-decoration: underline;
}

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

/* Mobile Menu */
.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text);
}

@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 1rem;
        box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    }

    .nav-links.active {
        display: flex;
    }

    .mobile-menu-btn {
        display: block;
    }

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