:root {
    --primary-color: #06b6d4; 
    --secondary-color: #94a3b8;
    --bg-color: #0f172a;     
    --card-bg: #1e293b; 
    --text-color: #e2e8f0; 
    --border-color: #334155; 
}

html { scroll-behavior: smooth; }
body {
    font-family: 'Prompt', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    margin: 0; padding: 0;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.7;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 20px;
}

h2 {
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 10px;
    margin-top: 0;
    font-size: 2.2rem;
    font-weight: 700;
}

.section > h2:first-of-type {
    margin-top: 0;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color 0.2s;
}
a:hover {
    color: #22d3ee;
    text-decoration: none;
}

.nav-link.active {
    background-color: var(--primary-color) !important;
    color: #ffffff !important;
}

.timeline {
    position: relative;
    max-width: 800px;
    margin-top: 20px;
}
.timeline-item {
    position: relative;
    padding: 10px 0 20px 30px;
    border-left: 2px solid var(--primary-color);
}
.timeline-item:last-child {
    border-left: 2px solid transparent;
}
.timeline-item::before {
    content: '';
    position: absolute;
    left: -11px;
    top: 12px;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--card-bg);
    border: 3px solid var(--primary-color);
}
.timeline-date {
    font-style: italic;
    color: var(--secondary-color);
    margin-bottom: 5px;
    font-weight: 500;
}
.timeline-item h4 {
    color: var(--text-color);
    margin-top: 0;
    margin-bottom: 5px;
}
.timeline-item p {
    color: var(--secondary-color);
}

.profile-wrapper {
    width: 150px; 
    height: 150px;
    position: relative; 
    flex-shrink: 0; 
    border-radius: 0.5rem;
    border: 4px solid var(--border-color);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    overflow: hidden; 
}
.profile-wrapper img {
    position: absolute;
    top: 0; left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover; 
}

@media (min-width: 768px) { 
    .profile-wrapper {
        width: 200px; 
        height: 200px;
    }
}
@media (max-width: 767px) { 
    #intro-box-container {
        flex-direction: column; 
        text-align: center;
        gap: 1.5rem; 
    }
    .profile-wrapper {
        margin: 0 auto; 
    }
    #intro h2 {
        text-align: center; 
    }
}