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

body {
    font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
    background-color: #fefefe;
    min-height: 100vh;
    padding: 20px;
}

.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
    border-bottom: 1px solid #e0e0e0;
    margin-bottom: 60px;
}

.nav-menu {
    display: flex;
    gap: 40px;
    list-style: none;
}

.nav-menu li a {
    text-decoration: none;
    color: #999;           /* Changed from #333 to grey */
    font-size: 18px;
    font-weight: 400;
    transition: color 0.3s ease;  /* Added smooth transition */
}

.nav-menu li a:hover {
    color: #333;
}

.nav-menu li a.active {
    color: #333;           /* Keep active page dark */
    font-weight: 500;
}

.signature {
    width: 180px;         
    height: 60px;        
    cursor: pointer;    
}

.signature img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.signature-link {
    text-decoration: none;
}

.signature-link:hover .signature {
    opacity: 0.8;         /* Subtle hover effect */
    transition: opacity 0.3s ease;
}

/* Global Submenu Styles */
.submenu-container {
    position: relative;
    height: 0;
    overflow: hidden;
    transition: height 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    margin-bottom: 40px;
}

.submenu-container.active {
    height: 60px;
}

.submenu {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    background-color: #fafafa;
    border-bottom: 1px solid #e0e0e0;
    transform: translateY(-100%);
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.submenu-container.active .submenu {
    transform: translateY(0);
}

.submenu-list {
    display: flex;
    justify-content: center;
    gap: 40px;
    list-style: none;
    padding: 20px 0;
    margin: 0;
}

.submenu-list li a {
    text-decoration: none;
    color: #666;
    font-size: 16px;
    font-weight: 300;
    transition: color 0.3s ease;
}

.submenu-list li a:hover {
    color: #333;
}

/* Homepage centered layout */
.main-content {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 60vh;
}

/* Section pages - single column layout */
.section-page {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 40px;
}

.center-nav {
    display: flex;
    gap: 80px;
    align-items: center;
}

.center-nav a {
    text-decoration: none;
    color: #ccc;
    font-size: 48px;
    font-weight: 300;
    transition: color 0.3s ease;
    letter-spacing: 2px;
}

.center-nav a:hover {
    color: #333;
}

/* Section Layouts */
.section-header {
    margin-bottom: 60px;
    padding-bottom: 40px;
    border-bottom: 1px solid #e0e0e0;
}

.section-content {
    font-size: 17px;
    line-height: 1.8;
    color: #444;
}

.section-title {
    font-size: 42px;
    font-weight: 300;
    color: #333;
    margin-bottom: 20px;
    letter-spacing: 1px;
}

.definition {
    font-family: 'Georgia', serif;
    font-size: 18px;
    color: #666;
    line-height: 1.6;
    font-style: italic;
}

.definition-label {
    font-weight: 600;
    color: #999;
    font-style: normal;
}

.definition-separator {
    margin: 0 8px;
    color: #ccc;
}

.section-content {
    max-width: 800px;
    margin: 0 auto;
    font-size: 17px;
    line-height: 1.8;
    color: #444;
}

.section-content p {
    margin-bottom: 24px;
}

.section-content h2 {
    font-size: 28px;
    font-weight: 400;
    color: #333;
    margin: 48px 0 20px;
    letter-spacing: 0.5px;
}

.section-content h3 {
    font-size: 20px;
    font-weight: 500;
    color: #555;
    margin: 32px 0 16px;
}

.section-content a {
    color: #666;
    text-decoration: none;
    border-bottom: 1px solid #ccc;
    transition: border-color 0.3s ease;
}

.section-content a:hover {
    border-bottom-color: #333;
}

/* Project List Styling */
.project-list {
    list-style: none;
    margin: 32px 0;
}

.project-list li {
    margin-bottom: 32px;
    padding-left: 0;
}

.project-title {
    font-size: 20px;
    font-weight: 500;
    color: #333;
    margin-bottom: 8px;
}

.project-meta {
    font-size: 15px;
    color: #999;
    margin-bottom: 8px;
}

.project-description {
    color: #666;
    line-height: 1.6;
}

@media (max-width: 768px) {
    .section-header,
    .section-content {
        max-width: 100%;
    }
    
    .section-title {
        font-size: 32px;
    }
    
    .definition {
        font-size: 16px;
    }
}



/* mobile flexible content */

@media (max-width: 768px) {
    .section-page {
        padding: 0 20px;
    }
    
    .nav-menu {
        gap: 20px;
    }
    
    .center-nav {
        flex-direction: column;
        gap: 40px;
    }
    
    .center-nav a {
        font-size: 36px;
    }
}