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

body {
    font-family: 'Segoe UI', 'Yu Gothic', 'Hiragino Kaku Gothic ProN', Meiryo, sans-serif;
    max-width: 1400px;
    margin: 0 auto;
    padding: 20px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    min-height: 100vh;
}

.header {
    text-align: center;
    margin-bottom: 40px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 40px 30px;
    border-radius: 15px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.header h1 {
    margin: 0;
    font-size: 2.5em;
    font-weight: 700;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.header p {
    margin: 15px 0 0 0;
    font-size: 1.2em;
    opacity: 0.95;
    font-weight: 300;
}

.search-container {
    margin: 20px 0;
    text-align: center;
}

.search-box {
    padding: 12px 20px;
    font-size: 15px;
    border: 2px solid #ddd;
    border-radius: 25px;
    width: 100%;
    max-width: 500px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    font-family: inherit;
}

.search-box:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 2px 12px rgba(102, 126, 234, 0.3);
}

.pdf-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-top: 20px;
    max-width: 1000px;
    margin-left: auto;
    margin-right: auto;
}

.pdf-entry {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.pdf-entry.has-links {
    margin-bottom: 16px;
}

.pdf-item {
    background: white;
    border-radius: 8px;
    padding: 12px 20px;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.06);
    border-left: 4px solid #667eea;
    display: flex;
    flex-direction: column;
    gap: 12px;
    color: inherit;
    cursor: default;
}

.pdf-item-header {
    display: flex;
    align-items: center;
    gap: 15px;
}

.pdf-item.important {
    background: #fff6b2;
    border-left-color: #d19a00;
}

.pdf-number {
    font-size: 0.95em;
    font-weight: 700;
    color: #667eea;
    font-family: 'Courier New', monospace;
    min-width: 30px;
    text-align: center;
}

.pdf-title {
    font-size: 0.95em;
    color: #333;
    flex-grow: 1;
    line-height: 1.4;
}

.pdf-source-links {
    margin: 0;
    padding: 0 0 0 24px;
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.pdf-source-item {
    display: flex;
    align-items: baseline;
    gap: 8px;
    font-size: 0.88em;
    color: #4a4a4a;
}

.pdf-source-bullet {
    color: #667eea;
    font-weight: 700;
}

.pdf-source-link {
    color: #3d4bb3;
    text-decoration: underline;
    display: inline-flex;
    align-items: center;
    gap: 0.35em;
    font-weight: 600;
}

.pdf-source-link:hover {
    color: #1e2a91;
}

.pdf-source-link:focus-visible {
    outline: 3px solid rgba(102, 126, 234, 0.35);
    outline-offset: 2px;
    border-radius: 4px;
}

.pdf-link-icon {
    font-size: 0.85em;
}

.pdf-entry.important .pdf-source-item {
    color: #8a6400;
}

.pdf-entry.important .pdf-source-bullet {
    color: #d19a00;
}

.pdf-entry.important .pdf-source-link {
    color: #a06000;
}

.pdf-entry.important .pdf-source-link:hover {
    color: #7a4800;
}

.pdf-download-link {
    font-weight: 700;
}

.no-results {
    text-align: center;
    padding: 40px 20px;
    color: #999;
    font-size: 1.1em;
}

@media (max-width: 768px) {
    body {
        padding: 15px;
    }
    
    .header h1 {
        font-size: 2em;
    }
    
    .header p {
        font-size: 1em;
    }
    
    .search-box {
        width: 100%;
    }

    .pdf-item {
        padding: 10px 15px;
        gap: 10px;
    }

    .pdf-number {
        min-width: 25px;
        font-size: 0.85em;
    }

    .pdf-title {
        font-size: 0.9em;
    }
}

@media (max-width: 480px) {
    .header {
        padding: 25px 20px;
    }
    
    .header h1 {
        font-size: 1.6em;
    }

    .pdf-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 5px;
    }

    .pdf-number {
        font-size: 0.8em;
    }

    .pdf-title {
        font-size: 0.85em;
    }
}