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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: #333;
}

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

header {
    text-align: center;
    margin-bottom: 40px;
    color: white;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

header p {
    font-size: 1.1rem;
    opacity: 0.9;
}

.search-section {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    margin-bottom: 30px;
}

.api-key-section {
    margin-bottom: 20px;
    padding: 20px;
    background: #f8f9fa;
    border-radius: 10px;
    border-left: 4px solid #007bff;
}

.api-key-section label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #495057;
}

.api-key-section input {
    width: 70%;
    padding: 12px;
    border: 2px solid #e9ecef;
    border-radius: 8px;
    font-size: 14px;
    margin-right: 10px;
}

.api-key-section input:focus {
    outline: none;
    border-color: #007bff;
    box-shadow: 0 0 0 3px rgba(0,123,255,0.1);
}

.api-key-section button {
    padding: 12px 20px;
    background: #007bff;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: background 0.3s;
}

.api-key-section button:hover {
    background: #0056b3;
}

.search-form {
    display: flex;
    gap: 15px;
    align-items: center;
}

.search-form input {
    flex: 1;
    padding: 15px;
    border: 2px solid #e9ecef;
    border-radius: 10px;
    font-size: 16px;
}

.search-form input:focus {
    outline: none;
    border-color: #28a745;
    box-shadow: 0 0 0 3px rgba(40,167,69,0.1);
}

.search-form button {
    padding: 15px 30px;
    background: #28a745;
    color: white;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    font-size: 16px;
    font-weight: 600;
    transition: all 0.3s;
}

.search-form button:hover {
    background: #218838;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(40,167,69,0.3);
}

.loading {
    text-align: center;
    padding: 40px;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.spinner {
    width: 50px;
    height: 50px;
    border: 5px solid #f3f3f3;
    border-top: 5px solid #007bff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.results-section {
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    overflow: hidden;
}

.chart-container {
    padding: 30px;
    border-bottom: 1px solid #e9ecef;
}

.chart-container h2 {
    margin-bottom: 20px;
    color: #495057;
    text-align: center;
}

.chart-container canvas {
    max-height: 400px;
}

.videos-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 20px;
    padding: 30px;
}

.video-card {
    background: #f8f9fa;
    border-radius: 12px;
    padding: 20px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.08);
    transition: all 0.3s ease;
    border: 1px solid #e9ecef;
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
}

.video-thumbnail {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 15px;
}

.video-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: #212529;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.video-channel {
    color: #6c757d;
    font-size: 0.9rem;
    margin-bottom: 15px;
}

.video-stats {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 10px;
    margin-bottom: 15px;
}

.stat-item {
    text-align: center;
    padding: 8px;
    background: white;
    border-radius: 6px;
    border: 1px solid #dee2e6;
}

.stat-value {
    font-weight: 600;
    color: #007bff;
    font-size: 0.9rem;
}

.stat-label {
    font-size: 0.8rem;
    color: #6c757d;
    margin-top: 2px;
}

.participation-rate {
    text-align: center;
    padding: 12px;
    background: linear-gradient(135deg, #28a745, #20c997);
    color: white;
    border-radius: 8px;
    font-weight: 600;
    font-size: 1.1rem;
}

.error {
    background: #f8d7da;
    color: #721c24;
    padding: 20px;
    border-radius: 10px;
    border: 1px solid #f5c6cb;
    text-align: center;
    margin-top: 20px;
}

@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    .search-form {
        flex-direction: column;
    }
    
    .api-key-section input {
        width: 100%;
        margin-bottom: 10px;
    }
    
    .videos-grid {
        grid-template-columns: 1fr;
        padding: 20px;
    }
    
    .video-stats {
        grid-template-columns: 1fr;
    }
}