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

:root {
    --primary-color: #667eea;
    --secondary-color: #764ba2;
    --text-dark: #2d3748;
    --text-light: #4a5568;
    --bg-light: #f7fafc;
    --bg-white: #ffffff;
    --border-color: #e2e8f0;
    --accent-color: #48bb78;
}

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

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

/* Header & Navigation */
header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

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

.logo-container {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo {
    height: 50px;
    width: auto;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
}

nav h1 {
    font-size: 1.8rem;
    font-weight: 700;
    margin: 0;
}

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

.nav-links a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.3s;
}

.nav-links a:hover {
    opacity: 0.8;
}

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

.hero-content h2 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.tagline {
    font-size: 1.5rem;
    opacity: 0.9;
    margin-bottom: 3rem;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 4rem;
    margin-top: 3rem;
}

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

.stat-number {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 1rem;
    opacity: 0.9;
}

/* Sections */
.section {
    padding: 5rem 0;
}

.section h2 {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    text-align: center;
    color: var(--text-dark);
}

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

/* About Section */
.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: center;
}

.about-text p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    color: var(--text-light);
}

.placeholder-image {
    width: 100%;
    max-width: 300px;
    margin: 0 auto;
}

.placeholder-image svg {
    width: 100%;
    height: auto;
}

/* Timeline */
.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 0;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 4px;
    height: 100%;
    background: var(--border-color);
}

.timeline-item {
    position: relative;
    margin-bottom: 3rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.timeline-item:nth-child(odd) .timeline-content {
    grid-column: 1;
    text-align: right;
}

.timeline-item:nth-child(even) .timeline-content {
    grid-column: 2;
    text-align: left;
}

.timeline-marker {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--primary-color);
    border: 4px solid var(--bg-white);
    z-index: 1;
}

.timeline-marker.future {
    background: var(--accent-color);
}

.timeline-content {
    background: var(--bg-white);
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.timeline-content h3 {
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.timeline-year {
    font-weight: 700;
    color: var(--accent-color);
    margin-bottom: 0.5rem;
}

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

.skill-card {
    background: var(--bg-white);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.skill-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
}

.skill-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.skill-card h3 {
    color: var(--primary-color);
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

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

.skill-card li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
    color: var(--text-light);
}

.skill-card li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--accent-color);
    font-weight: 700;
}

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

.contact-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    color: var(--text-light);
}

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

.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

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

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

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

footer p {
    opacity: 0.8;
}

/* Responsive Design */
@media (max-width: 1024px) {
    .container {
        padding: 0 30px;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 20px;
    }

    nav h1 {
        font-size: 1.4rem;
    }

    .nav-links {
        gap: 1rem;
        font-size: 0.85rem;
    }

    .hero {
        padding: 3rem 0;
    }

    .hero-content h2 {
        font-size: 2rem;
        line-height: 1.2;
    }

    .tagline {
        font-size: 1.2rem;
    }

    .hero-stats {
        flex-direction: column;
        gap: 2rem;
    }

    .stat-number {
        font-size: 2.5rem;
    }

    .about-content {
        grid-template-columns: 1fr;
    }

    .about-text p {
        font-size: 1rem;
    }

    .timeline::before {
        left: 20px;
    }

    .timeline-item {
        grid-template-columns: 1fr;
        padding-left: 50px;
    }

    .timeline-item:nth-child(odd) .timeline-content,
    .timeline-item:nth-child(even) .timeline-content {
        grid-column: 1;
        text-align: left;
    }

    .timeline-marker {
        left: 20px;
    }

    .timeline-content {
        padding: 1.25rem;
    }

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

    .section {
        padding: 3rem 0;
    }

    .section h2 {
        font-size: 2rem;
        margin-bottom: 2rem;
    }

    .contact-content p {
        font-size: 1rem;
    }

    .btn {
        padding: 0.75rem 1.5rem;
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    nav h1 {
        font-size: 1.2rem;
    }

    .nav-links {
        gap: 0.75rem;
        font-size: 0.8rem;
    }

    .hero-content h2 {
        font-size: 1.5rem;
    }

    .tagline {
        font-size: 1rem;
    }

    .stat-number {
        font-size: 2rem;
    }

    .stat-label {
        font-size: 0.9rem;
    }

    .section h2 {
        font-size: 1.75rem;
    }

    .skill-card {
        padding: 1.5rem;
    }

    .contact-links {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }
}