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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Arial, sans-serif;
    background-color: #1a1a1a;
    color: #e0e0e0;
    line-height: 1.6;
}

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

header {
    text-align: center;
    padding: 40px 0;
    border-bottom: 1px solid #333;
    margin-bottom: 40px;
}

h1 {
    font-size: 2.5rem;
    color: #fff;
    margin-bottom: 10px;
}

header p {
    color: #888;
    font-size: 1.1rem;
}

.controls {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
}

button {
    background-color: #2a2a2a;
    color: #e0e0e0;
    border: 1px solid #444;
    padding: 12px 24px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    transition: all 0.2s;
}

button:hover {
    background-color: #333;
    border-color: #555;
}

.pdf-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

.pdf-card {
    background-color: #242424;
    border: 1px solid #333;
    border-radius: 6px;
    padding: 20px;
    transition: all 0.2s;
}

.pdf-card:hover {
    border-color: #555;
    background-color: #2a2a2a;
}

.pdf-card h3 {
    color: #fff;
    margin-bottom: 10px;
    font-size: 1.3rem;
}

.description {
    color: #aaa;
    margin-bottom: 15px;
}

.meta {
    color: #777;
    font-size: 0.9rem;
    margin-bottom: 5px;
}

.actions {
    display: flex;
    gap: 10px;
    margin-top: 15px;
}

.btn {
    padding: 10px 20px;
    border-radius: 4px;
    text-decoration: none;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.2s;
    border: 1px solid;
}

.btn-primary {
    background-color: #444;
    color: #fff;
    border-color: #555;
}

.btn-primary:hover {
    background-color: #555;
}

.btn-secondary {
    background-color: transparent;
    color: #aaa;
    border-color: #444;
}

.btn-secondary:hover {
    background-color: #2a2a2a;
    color: #e0e0e0;
}

.validation-results {
    background-color: #242424;
    border: 1px solid #333;
    border-radius: 6px;
    padding: 20px;
    margin-top: 20px;
}

.validation-results h2 {
    color: #fff;
    margin-bottom: 15px;
    font-size: 1.3rem;
}

.validation-item {
    padding: 10px;
    margin-bottom: 8px;
    border-radius: 4px;
    background-color: #2a2a2a;
}

.validation-item.valid {
    border-left: 3px solid #4a9960;
}

.validation-item.invalid {
    border-left: 3px solid #994a4a;
}

.loading,
.empty,
.error {
    text-align: center;
    padding: 40px;
    color: #888;
    font-size: 1.1rem;
}

.error {
    color: #994a4a;
}