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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.8) 0%, rgba(118, 75, 162, 0.8) 100%), url('world_background.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    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: 3rem;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

header p {
    font-size: 1.2rem;
    opacity: 0.9;
}

.search-section {
    background: white;
    border-radius: 15px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    margin-bottom: 30px;
}

.search-container {
    position: relative;
    margin-bottom: 25px;
}

#countrySearch {
    width: 100%;
    padding: 15px 20px;
    font-size: 16px;
    border: 2px solid #e0e0e0;
    border-radius: 10px;
    outline: none;
    transition: all 0.3s ease;
}

#countrySearch:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.dropdown {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: white;
    border: 1px solid #e0e0e0;
    border-top: none;
    border-radius: 0 0 10px 10px;
    max-height: 200px;
    overflow-y: auto;
    z-index: 1000;
    display: none;
}

.dropdown-item {
    padding: 12px 20px;
    cursor: pointer;
    transition: background-color 0.2s;
    border-bottom: 1px solid #f0f0f0;
}

.dropdown-item:hover {
    background-color: #f8f9ff;
}

.dropdown-item:last-child {
    border-bottom: none;
}

.keyboard-hints {
    margin-top: 8px;
    text-align: center;
}

.keyboard-hints small {
    color: #888;
    font-size: 12px;
}

.keyboard-hints strong {
    color: #667eea;
    font-weight: 600;
}

.selected-countries h3 {
    margin-bottom: 15px;
    color: #555;
}

.country-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 25px;
    min-height: 40px;
}

.country-tag {
    background: linear-gradient(45deg, #667eea, #764ba2);
    color: white;
    padding: 8px 15px;
    border-radius: 20px;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.country-tag .remove {
    background: rgba(255,255,255,0.2);
    border-radius: 50%;
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background-color 0.2s;
    font-size: 12px;
}

.country-tag .remove:hover {
    background: rgba(255,255,255,0.3);
}

.controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.year-range {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.year-range small {
    font-size: 12px;
    color: #666;
    font-style: italic;
}

.year-range label {
    font-weight: 600;
    color: #555;
}

.year-range select {
    padding: 8px 12px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 14px;
    outline: none;
    transition: border-color 0.3s;
}

.year-range select:focus {
    border-color: #667eea;
}

.query-btn {
    background: linear-gradient(45deg, #667eea, #764ba2);
    color: white;
    border: none;
    padding: 15px 30px;
    border-radius: 10px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.query-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.query-btn:disabled {
    background: #ccc;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.loading {
    background: white;
    border-radius: 15px;
    padding: 40px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    margin-bottom: 30px;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #667eea;
    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;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    margin-bottom: 30px;
}

.chart-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
    flex-wrap: wrap;
    gap: 15px;
}

.toggle-btn, .download-btn {
    background: #f8f9ff;
    border: 2px solid #667eea;
    color: #667eea;
    padding: 10px 20px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s ease;
}

.toggle-btn:hover, .download-btn:hover {
    background: #667eea;
    color: white;
}

.chart-container {
    position: relative;
    height: 500px;
    margin-bottom: 30px;
}

.table-container {
    overflow-x: auto;
    margin-bottom: 30px;
}

#populationTable {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
}

#populationTable th,
#populationTable td {
    padding: 12px;
    text-align: right;
    border-bottom: 1px solid #e0e0e0;
}

#populationTable th {
    background: #f8f9ff;
    font-weight: 600;
    color: #555;
    position: sticky;
    top: 0;
    z-index: 10;
}

#populationTable th:first-child,
#populationTable td:first-child {
    text-align: left;
    font-weight: 600;
}

#populationTable tr:hover {
    background: #f8f9ff;
}

.stats-summary {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.stat-card {
    background: linear-gradient(45deg, #f8f9ff, #fff);
    padding: 20px;
    border-radius: 10px;
    border-left: 4px solid #667eea;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.stat-card h4 {
    color: #555;
    margin-bottom: 10px;
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.stat-card .value {
    font-size: 24px;
    font-weight: 700;
    color: #667eea;
    margin-bottom: 5px;
}

.stat-card .description {
    font-size: 12px;
    color: #888;
}

footer {
    text-align: center;
    color: white;
    opacity: 0.8;
    margin-top: 40px;
}

footer a {
    color: white;
    text-decoration: underline;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 15px;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    .controls {
        flex-direction: column;
        align-items: stretch;
    }
    
    .year-range {
        justify-content: space-between;
    }
    
    .chart-controls {
        flex-direction: column;
        align-items: stretch;
    }
    
    .chart-container {
        height: 400px;
    }
    
    .stats-summary {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    header h1 {
        font-size: 1.8rem;
    }
    
    header p {
        font-size: 1rem;
    }
    
    .search-section,
    .results-section {
        padding: 20px;
    }
    
    .country-tags {
        justify-content: center;
    }
    
    .chart-container {
        height: 300px;
    }
}