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

body {
    font-family: Arial, sans-serif;
    background-color: #f5f5f5;
}

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

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    padding: 20px 0;
}

.main-nav {
    margin: 0 30px;
}

.main-nav ul {
    list-style: none;
    display: flex;
    gap: 30px;
    margin: 0;
    padding: 0;
}

.nav-item {
    text-decoration: none;
    color: #666;
    font-weight: 500;
    padding: 8px 16px;
    border-radius: 20px;
    transition: all 0.3s ease;
    position: relative;
}

.nav-item:hover {
    color: #007bff;
    background-color: rgba(0, 123, 255, 0.1);
}

.nav-item.active {
    color: #007bff;
    background-color: rgba(0, 123, 255, 0.15);
    font-weight: 600;
}

.nav-item.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 30px;
    height: 2px;
    background-color: #007bff;
    border-radius: 1px;
}

h1 {
    color: #333;
}

.btn {
    padding: 10px 20px;
    background-color: #007bff;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    transition: background-color 0.3s;
}

.btn:hover {
    background-color: #0056b3;
}

.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 25px;
    margin-top: 20px;
}

/* Center the last chart when it's alone in its row */
.dashboard-grid .chart-container:last-child {
    grid-column: 1 / -1; /* Span full width */
    max-width: 500px; /* Limit width for better appearance */
    margin: 0 auto; /* Center align */
    justify-self: center; /* Center within grid cell */
}

/* Adjust layout for smaller screens */
@media (max-width: 900px) {
    .dashboard-grid {
        grid-template-columns: 1fr;
    }

    /* On mobile, remove special centering for last chart */
    .dashboard-grid .chart-container:last-child {
        max-width: none;
        margin: 0;
        justify-self: stretch;
    }
}

.chart-container {
    background: linear-gradient(135deg, #ffffff 0%, #f8f9fa 100%);
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    min-height: 400px;
    position: relative;
}

.chart-container:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.15);
}

.chart-container canvas {
    max-height: 350px !important;
}

#user-info {
    display: flex;
    align-items: center;
    gap: 15px;
}

#exportPDF {
    background: linear-gradient(135deg, #e74c3c 0%, #c0392b 100%) !important;
    border: none !important;
    color: white !important;
    padding: 10px 20px !important;
    border-radius: 25px !important;
    font-weight: 600 !important;
    cursor: pointer !important;
    transition: all 0.3s ease !important;
    box-shadow: 0 4px 15px rgba(231, 76, 60, 0.3) !important;
    text-decoration: none !important;
    font-size: 14px !important;
}

#exportPDF:hover {
    transform: translateY(-2px) !important;
    box-shadow: 0 6px 20px rgba(231, 76, 60, 0.4) !important;
    background: linear-gradient(135deg, #c0392b 0%, #e74c3c 100%) !important;
}

#exportPDF:active {
    transform: translateY(0) !important;
}

#user-info span {
    color: #333;
    font-weight: 500;
}

.controls-container {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 25px;
    border-radius: 12px;
    margin-bottom: 25px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    display: flex;
    gap: 25px;
    align-items: center;
    flex-wrap: wrap;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.control-group {
    display: flex;
    align-items: center;
    gap: 10px;
}

.control-group label {
    color: #fff;
    font-weight: 600;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.1);
}

.control-group select,
.control-group input {
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
    min-width: 200px;
}

#sheetSelect {
    background-color: #fff;
    border: 3px solid #007bff !important;
    box-shadow: 0 4px 8px rgba(0,123,255,0.3) !important;
    padding: 10px !important;
    font-size: 16px !important;
    font-weight: bold !important;
    color: #333 !important;
    min-width: 300px !important;
    display: block !important;
    visibility: visible !important;
    opacity: 1 !important;
}

#applyFilters {
    margin-left: auto;
    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a24 100%);
    border: none;
    color: white;
    padding: 12px 24px;
    border-radius: 25px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(238, 90, 36, 0.3);
}

#applyFilters:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(238, 90, 36, 0.4);
    background: linear-gradient(135deg, #ee5a24 0%, #ff6b6b 100%);
}

#applyFilters:active {
    transform: translateY(0);
}

.loading {
    opacity: 0.6;
    pointer-events: none;
}

.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 20px;
    height: 20px;
    margin: -10px 0 0 -10px;
    border: 2px solid #f3f3f3;
    border-top: 2px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

.chart-title {
    font-size: 18px;
    font-weight: bold;
    color: #333;
    margin-bottom: 15px;
    text-align: center;
}