/* CSS Custom Properties */
:root {
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    --success: #10b981;
    --success-bg: #d1fae5;
    --warning: #f59e0b;
    --warning-bg: #fef3c7;
    --danger: #ef4444;
    --danger-bg: #fee2e2;
    --white: #ffffff;
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --radius: 0.5rem;
}

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background-color: var(--gray-50);
    color: var(--gray-800);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

a {
    text-decoration: none;
    color: inherit;
}

/* Navbar Styles */
.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 2rem;
    background-color: var(--white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-brand a {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
}

.nav-links {
    display: flex;
    gap: 0.5rem;
}

.nav-links a {
    padding: 0.5rem 1rem;
    border-radius: var(--radius);
    color: var(--gray-600);
    font-weight: 500;
    transition: background-color 0.2s, color 0.2s;
}

.nav-links a:hover {
    background-color: var(--gray-100);
    color: var(--gray-800);
}

.nav-links a.active {
    background-color: var(--primary);
    color: var(--white);
}

.nav-actions {
    display: flex;
    gap: 0.5rem;
}

/* Year Filter Styles */
.year-filter {
    display: flex;
    justify-content: center;
    gap: 0.25rem;
    padding: 1rem 2rem;
    background-color: var(--white);
    border-bottom: 1px solid var(--gray-200);
}

.year-btn {
    padding: 0.5rem 1rem;
    border-radius: var(--radius);
    color: var(--gray-600);
    font-weight: 500;
    font-size: 0.875rem;
    transition: background-color 0.2s, color 0.2s;
}

.year-btn:hover {
    background-color: var(--gray-100);
    color: var(--gray-800);
}

.year-btn.active {
    background-color: var(--gray-800);
    color: var(--white);
}

/* Container */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
    flex: 1;
}

/* Button Styles */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem 1rem;
    border-radius: var(--radius);
    font-weight: 500;
    font-size: 0.875rem;
    border: none;
    cursor: pointer;
    transition: background-color 0.2s, color 0.2s;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-primary {
    background-color: var(--primary);
    color: var(--white);
}

.btn-primary:hover:not(:disabled) {
    background-color: var(--primary-hover);
}

.btn-secondary {
    background-color: var(--gray-200);
    color: var(--gray-700);
}

.btn-secondary:hover:not(:disabled) {
    background-color: var(--gray-300);
}

.btn-danger {
    background-color: var(--danger);
    color: var(--white);
}

.btn-danger:hover:not(:disabled) {
    background-color: #dc2626;
}

.btn-sm {
    padding: 0.25rem 0.5rem;
    font-size: 0.75rem;
}

/* Card Styles */
.card {
    background-color: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 1.5rem;
}

.card-title {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--gray-500);
    margin-bottom: 0.5rem;
}

.card-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--gray-900);
}

.card-subtitle {
    font-size: 0.75rem;
    color: var(--gray-400);
    margin-top: 0.25rem;
}

/* Grid Layout */
.grid {
    display: grid;
    gap: 1.5rem;
}

.grid-4 {
    grid-template-columns: repeat(4, 1fr);
}

.grid-3 {
    grid-template-columns: repeat(3, 1fr);
}

.grid-2 {
    grid-template-columns: repeat(2, 1fr);
}

/* Table Styles */
table {
    width: 100%;
    border-collapse: collapse;
    background-color: var(--white);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
}

thead {
    background-color: var(--gray-50);
}

th {
    text-align: left;
    padding: 0.75rem 1rem;
    font-weight: 600;
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--gray-500);
    border-bottom: 1px solid var(--gray-200);
}

td {
    padding: 1rem;
    border-bottom: 1px solid var(--gray-100);
    color: var(--gray-700);
}

tbody tr:hover {
    background-color: var(--gray-50);
}

tbody tr:last-child td {
    border-bottom: none;
}

/* Status Classes */
.status-active {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 500;
    background-color: var(--success-bg);
    color: var(--success);
}

.status-cancelled {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 500;
    background-color: var(--danger-bg);
    color: var(--danger);
}

.status-pending {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 500;
    background-color: var(--warning-bg);
    color: var(--warning);
}

/* Footer Styles */
.footer {
    padding: 1.5rem 2rem;
    text-align: center;
    color: var(--gray-500);
    font-size: 0.875rem;
    background-color: var(--white);
    border-top: 1px solid var(--gray-200);
    margin-top: auto;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.text-right {
    text-align: right;
}

.text-muted {
    color: var(--gray-500);
}

.text-success {
    color: var(--success);
}

.text-warning {
    color: var(--warning);
}

.text-danger {
    color: var(--danger);
}

.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-4 { margin-top: 1rem; }
.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-4 { margin-bottom: 1rem; }

/* Responsive Media Queries */
@media (max-width: 1024px) {
    .grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }

    .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }

    .navbar {
        padding: 1rem;
    }

    .nav-links a {
        padding: 0.5rem 0.75rem;
        font-size: 0.875rem;
    }

    .container {
        padding: 1.5rem;
    }
}

@media (max-width: 640px) {
    .navbar {
        flex-direction: column;
        gap: 1rem;
    }

    .nav-links {
        flex-wrap: wrap;
        justify-content: center;
    }

    .nav-links a {
        padding: 0.5rem;
        font-size: 0.75rem;
    }

    .year-filter {
        flex-wrap: wrap;
        padding: 0.75rem;
    }

    .year-btn {
        padding: 0.375rem 0.75rem;
        font-size: 0.75rem;
    }

    .grid-4,
    .grid-3,
    .grid-2 {
        grid-template-columns: 1fr;
    }

    .container {
        padding: 1rem;
    }

    .card-value {
        font-size: 1.5rem;
    }

    table {
        font-size: 0.875rem;
    }

    th, td {
        padding: 0.5rem;
    }
}