:root {
    /* Color palette */
    --primary-color: #2c6abc;
    --primary-dark: #1a4a8f;
    --primary-light: #4386dc;
    --accent-color: #ff6b35;
    --text-color: #333333;
    --text-light: #666666;
    --background-light: #f5f7fa;
    --background-dark: #e0e5ec;
    --white: #ffffff;
    --shadow: rgba(0, 0, 0, 0.1);

    /* Project type colors */
    --residential-color: #ff8c00;
    --commercial-color: #1e88e5;
    --transportation-color: #43a047;
    --industrial-color: #6a1b9a;

    /* Status colors */
    --completed-color: #4caf50;
    --in-progress-color: #ff9800;
    --planned-color: #2196f3;

    /* Typography */
    --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --heading-font: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;

    /* Borders */
    --border-radius-sm: 4px;
    --border-radius-md: 8px;
    --border-radius-lg: 12px;

    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.1);

    /* Animation */
    --transition-fast: 0.15s ease-in-out;
    --transition-normal: 0.3s ease-in-out;
}

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

body {
    font-family: var(--font-family);
    color: var(--text-color);
    background-color: var(--background-light);
    line-height: 1.6;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: var(--heading-font);
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
}

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--primary-dark);
}

.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.app-header {
    background-color: var(--white);
    border-bottom: 1px solid var(--background-dark);
    padding: var(--spacing-md) var(--spacing-xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: var(--shadow-sm);
    z-index: 100;
}

.brand h1 {
    font-size: 1.5rem;
    margin: 0;
    color: var(--primary-dark);
}

.header-actions {
    display: flex;
    gap: var(--spacing-md);
}

.app-content {
    flex: 1;
    display: flex;
    position: relative;
}

.app-footer {
    background-color: var(--white);
    border-top: 1px solid var(--background-dark);
    padding: var(--spacing-md) var(--spacing-xl);
    text-align: center;
    font-size: 0.9rem;
    color: var(--text-light);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Button Styles */
.btn {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius-sm);
    background-color: var(--primary-color);
    color: var(--white);
    font-weight: 500;
    cursor: pointer;
    transition: background-color var(--transition-fast);
    border: none;
    outline: none;
    font-family: var(--font-family);
}

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

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

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

.btn-text {
    background: none;
    color: var(--primary-color);
    border: none;
    padding: var(--spacing-xs) var(--spacing-sm);
    font: inherit;
    cursor: pointer;
    text-decoration: underline;
    font-size: 0.9rem;
}

.btn-text:hover {
    color: var(--primary-dark);
}

.btn-icon {
    background: none;
    border: none;
    color: var(--text-color);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: color var(--transition-fast);
}

.btn-icon:hover {
    color: var(--primary-color);
}

/* Toast Notification */
.toast-container {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    z-index: 9999;
}

.toast {
    background-color: var(--primary-color);
    color: var(--white);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--border-radius-md);
    margin-top: var(--spacing-md);
    box-shadow: var(--shadow-md);
    opacity: 0;
    transform: translateY(20px);
    animation: toast-in 0.3s ease forwards;
}

@keyframes toast-in {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.modal.active {
    display: flex;
}

.modal-content {
    background-color: var(--white);
    border-radius: var(--border-radius-md);
    width: 90%;
    max-width: 600px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) var(--spacing-lg);
    border-bottom: 1px solid var(--background-dark);
}

.modal-body {
    padding: var(--spacing-lg);
}

.modal-footer {
    padding: var(--spacing-md) var(--spacing-lg);
    border-top: 1px solid var(--background-dark);
    text-align: right;
}

.close-modal {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-light);
}

/* Responsive */
@media (max-width: 768px) {
    .app-header {
        padding: var(--spacing-md);
    }

    .brand h1 {
        font-size: 1.2rem;
    }

    .sidebar {
        width: 100%;
        max-width: none;
        position: fixed;
        z-index: 90;
        transform: translateX(-100%);
    }

    .sidebar.active {
        transform: translateX(0);
    }

    .details-panel {
        width: 100%;
        max-width: none;
    }
}