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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    max-width: 1000px;
    margin: 0 auto;
    padding: 20px;
    background-color: #f9f9f9;
}

/* Header & Navigation Layout */
header {
    background-color: #fff;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    margin-bottom: 30px;
}

h1 {
    font-size: 2.5rem;
    color: #222;
    margin-bottom: 20px;
    border-bottom: 2px solid #eaeaea;
    padding-bottom: 10px;
}

nav {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 15px;
    padding-bottom: 15px;
}

nav.main-nav {
    border-bottom: 1px solid #eaeaea;
}

nav a, nav button {
    text-decoration: none;
    color: #0066cc;
    font-weight: 500;
    padding: 6px 12px;
    border-radius: 4px;
    background-color: #f0f4f8;
    border: none;
    cursor: pointer;
    font-family: inherit;
    transition: background-color 0.2s, color 0.2s;
}

nav a:hover, nav button:hover {
    background-color: #0066cc;
    color: #fff;
}

nav button.active {
    background-color: #333;
    color: #fff;
}

/* Content Area */
main {
    background-color: #fff;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    min-height: 300px;
}

main p {
    margin-bottom: 25px;
}

/* Portfolio Sections */
.portfolio-section {
    display: none;
    margin-top: 20px;
    animation: fadeIn 0.3s ease-in-out;
}

.portfolio-section.active-section {
    display: block;
}

.portfolio-section h2 {
    color: #444;
    margin-bottom: 15px;
    border-bottom: 1px solid #eee;
    padding-bottom: 5px;
}

/* Piece Groups */
.piece-group {
    margin-bottom: 20px;
    padding: 15px;
    background: #fdfdfd;
    border: 1px solid #eef2f5;
    border-radius: 6px;
}

.piece-title {
    font-weight: 600;
    margin-bottom: 10px;
    color: #2c3e50;
}

/* PDF Download Links Layout */
.pdf-links {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.pdf-links a {
    display: inline-flex;
    align-items: center;
    color: #0066cc;
    text-decoration: none;
    font-weight: 500;
    padding: 4px 10px;
    background: #fff;
    border: 1px solid #d0e2f3;
    border-radius: 4px;
    transition: all 0.2s;
}

.pdf-links a:hover {
    background: #e6f2ff;
    border-color: #0066cc;
    text-decoration: none;
}

.pdf-links a.score-link {
    background: #fff9e6;
    border-color: #ffe0b2;
    color: #b78103;
}

.pdf-links a.score-link:hover {
    background: #fff3cd;
    border-color: #b78103;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(5px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Footer */
footer {
    margin-top: 40px;
    text-align: center;
    font-size: 0.9rem;
    color: #666;
    border-top: 1px solid #eaeaea;
    padding-top: 20px;
}

/* Shared Box / Button Links (e.g., CV button, Project list buttons) */
.btn-box, .project-link {
    display: inline-block;
    text-decoration: none;
    color: #0066cc;
    font-weight: 500;
    padding: 6px 12px;
    border-radius: 4px;
    background-color: #f0f4f8;
    transition: background-color 0.2s, color 0.2s;
}

.btn-box:hover, .project-link:hover {
    background-color: #0066cc;
    color: #fff;
    text-decoration: none;
}

/* Optional: Spacing for list items */
.project-list {
    margin-top: 20px;
    padding-left: 0;
    list-style-type: none;
}
.project-list li {
    margin-bottom: 15px;
}