:root {
  /* Brand / βασικό χρώμα 
  --color-primary: #2a5298;
  --color-primary-dark: #1e3c72;
  */
    --color-primary: #1e4f07;
    --color-primary-dark: #145006;
}

/* Reset & Base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Noto Sans', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

.container {
    max-width: 1200px;
    margin-top: 100px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.site-header {
    background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 100%);
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.header-content {
    text-align: center;
}
.logo-section {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    justify-content: center;
}

.header-logo {
    height: 120px;
    width: auto;
    /* filter: brightness(0) invert(1);  Κάνει το logo λευκό */
}

.header-text {
    text-align: left;
}

/* Responsive */
@media (max-width: 768px) {
    .logo-section {
        flex-direction: column;
        gap: 1rem;
    }
    
    .header-text {
        text-align: center;
    }
    
    .header-logo {
        height: 60px;
    }
}
.site-header h1 {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}
.dept-link {
    color: white;
    text-decoration: none;
    border-bottom: 1px dotted rgba(255,255,255,0.5);
    transition: border-color 0.3s;
}

.dept-link:hover {
    border-bottom-color: white;
}
.subtitle {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* Navigation */
.main-nav {
    background-color: var(--color-primary);;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-list {
    list-style: none;
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
}

.nav-list li {
    margin: 0;
}

.nav-list a {
    display: block;
    padding: 1rem 1.5rem;
    color: white;
    text-decoration: none;
    transition: background-color 0.3s ease;
}
/* Dropdown Menu */
.dropdown {
    position: relative;
}

.dropdown-content {
    display: none;
    position: absolute;
    background-color: var(--color-primary-dark);
    min-width: 220px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    z-index: 1000;
    list-style: none;
    padding: 0;
    margin: 0;
}

.dropdown:hover .dropdown-content {
    display: block;
}

.dropdown-content li {
    margin: 0;
}

.dropdown-content a {
    padding: 0.8rem 1.5rem;
    display: block;
}

.dropdown-content a:hover {
    background-color: var(--color-primary);
}
.nav-list a:hover,
.nav-list a.active {
    background-color: var(--color-primary-dark);
}

/* Main Content */
main {
    background-color: white;
    margin: 2rem auto;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    min-height: 60vh;
}

.page-content {
    max-width: 900px;
    margin: 0 auto;
}

/* Sections */
section {
    margin-bottom: 3rem;
}

section h2 {
    color: var(--color-primary-dark);
    font-size: 1.8rem;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 3px solid var(--color-primary);
}

.lead {
    font-size: 1.2rem;
    font-weight: 500;
    color: #555;
    margin-bottom: 1rem;
}

/* Lists */
.goals-list {
    margin-left: 1.5rem;
    margin-top: 1rem;
}

.goals-list li {
    margin-bottom: 1rem;
    padding-left: 0.5rem;
}

.topics-list {
    list-style: none;
    margin-top: 1rem;
}

.topics-list li {
    padding: 0.8rem;
    margin-bottom: 0.5rem;
    background-color: #f0f4f8;
    border-left: 4px solid var(--color-primary);
    border-radius: 4px;
}

/* Team Grid */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.team-member {
    background-color: #f8f9fa;
    padding: 1.5rem;
    border-radius: 8px;
    border: 1px solid #e0e0e0;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.team-member:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.team-member h3 {
    color: var(--color-primary-dark);
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.team-member .role {
    color: #666;
    font-size: 0.95rem;
}

.team-member .role strong {
    color: var(--color-primary);
}
.contact-links {
    display: flex;
    gap: 0.8rem;
    margin-top: 0.8rem;
    flex-wrap: wrap;
}

.contact-link {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    padding: 0.4rem 0.8rem;
    background-color: #e8f4f8;
    color: var(--color-primary);
    text-decoration: none;
    border-radius: 4px;
    font-size: 0.85rem;
    transition: all 0.3s;
}

.contact-link:hover {
    background-color: var(--color-primary);
    color: white;
    transform: translateY(-2px);
}
/* Footer */
.site-footer {
    background-color: var(--color-primary-dark);
    color: white;
    text-align: center;
    padding: 1rem 0;
    margin-top: 1rem;
}

.site-footer p {
    margin: 0;
    opacity: 0.9;
}
.site-footer .dept-link {
    color: white;
    border-bottom-color: rgba(255,255,255,0.4);
}

.site-footer .dept-link:hover {
    border-bottom-color: white;
}
/* Responsive */
@media (max-width: 768px) {
    .site-header h1 {
        font-size: 1.4rem;
    }
    
    .subtitle {
        font-size: 0.95rem;
    }
    
    .nav-list {
        flex-direction: column;
    }
    
    .nav-list a {
        text-align: center;
    }
    
    main {
        margin: 1rem auto;
        padding: 1rem;
    }
    
    section h2 {
        font-size: 1.5rem;
    }
    
    .team-grid {
        grid-template-columns: 1fr;
    }
}
/* Thesis lists & PDF links */
.thesis-list {
    margin-top: 1rem;
}

.thesis-list li {
    margin-bottom: 1.2rem;
    line-height: 1.8;
}

.pdf-link {
    display: inline-block;
    margin-left: 0.5rem;
    padding: 0.3rem 0.8rem;
    background-color: #e8f4f8;
    color: var(--color-primary);
    text-decoration: none;
    border-radius: 4px;
    font-size: 0.9rem;
    transition: background-color 0.3s;
}

.pdf-link:hover {
    background-color: var(--color-primary);
    color: white;
}