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

/* Global Box-Sizing */
html {
    box-sizing: border-box;
    font-size: 16px; /* Base font size for rem calculations */
}


:root {
    /* Modern Color Palette */
    --primary-dark: #2c3e50; /* Darker, more muted blue for primary elements */
    --accent-gold: #f39c12; /* Vibrant gold for accents */
    --text-light: #ecf0f1; /* Light gray for text on dark backgrounds */
    --text-dark: #34495e; /* Dark gray for text on light backgrounds */
    --background-light: #ffffff; /* Pure white background */
    --background-grey: #f8f9fa; /* Off-white for subtle sections */
    --border-color: #e0e0e0; /* Light gray for borders */
    --hover-bg: rgba(0, 0, 0, 0.05); /* Subtle hover background */
    --gradient-start: #2c3e50; /* For login page gradient */
    --gradient-end: #4a279c; /* For login page gradient */


    /* Spacing Scale */
    --spacing-xs: 0.25rem; /* New smaller spacing unit */
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem; /* This is our original --gutter */
    --spacing-xl: 2.5rem;
    --spacing-xxl: 4rem; /* New larger spacing unit */

    --sidebar-width: 16rem;
    --border-radius: 8px;
    --transition-speed: 0.3s;
}

/* Global Styles - Mobile First Defaults */
body {
    font-family: 'Inter', 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--background-grey);
    margin: 0;
    padding: 0;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    font-size: var(--spacing-md); /* Base font size for mobile */
}

h1, h2, h3, h4, h5, h6 {
    color: var(--primary-dark);
    margin-bottom: var(--spacing-sm);
    font-weight: 700;
    line-height: 1.2;
}

h1 { font-size: 1.8rem; margin-bottom: var(--spacing-xl); } /* Consistent large margin for main titles */
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.1rem; }
h5 { font-size: 1rem; }
h6 { font-size: 0.9rem; }


a {
    color: var(--primary-dark);
    text-decoration: none;
    transition: color var(--transition-speed) ease;
}

a:hover {
    color: var(--accent-gold);
    text-decoration: underline;
}

/* Utility Classes */
.d-flex { display: flex !important; }
.justify-content-between { justify-content: space-between !important; }
.align-items-center { align-items: center !important; }
.p-4 { padding: var(--spacing-lg) !important; }
.mt-4 { margin-top: var(--spacing-lg) !important; }
.mb-4 { margin-bottom: var(--spacing-lg) !important; }


/* Layout - Main Wrapper */
#wrapper {
    display: flex;
    flex-direction: column; /* Stack sidebar and content vertically on mobile */
    
    position: relative;
    background-color: var(--background-grey);
}

/* Sidebar Styles - Mobile First (Hidden by default, fixed overlay) */
.sidebar {
    width: var(--sidebar-width);
    min-width: var(--sidebar-width);
    background-color: var(--primary-dark);
    color: var(--text-light);
    box-shadow: 3px 0 10px rgba(0,0,0,0.15);

    position: fixed;
    height: 100%;
    z-index: 1030;
    top: 0;
    left: 0;
    transform: translateX(-100%); /* Hidden by default */
    transition: transform var(--transition-speed) ease-out;
    display: flex;
    flex-direction: column;
    will-change: transform; /* Hint for smoother animation */
}

.sidebar-header {
    padding: var(--spacing-lg) var(--spacing-md);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Remove default h3 spacing */
.sidebar-title {
    margin: 0;
    padding: 0;
    display: flex;
    align-items: center;
}

/* Logo styling */
.sidebar-logo {
    height: 40px;   /* Fixed height for consistency */
    width: auto;
    display: block;
}

/* Optional: Better close button alignment */
.close-sidebar-btn {
    display: flex;
    align-items: center;
    justify-content: center;
}


.sidebar-nav {
    list-style: none;
    padding: 0;
    flex-grow: 1;
    overflow-y: auto; /* Enable scrolling for nav content if it overflows */
}

.sidebar-nav .nav-link {
    display: block;
    padding: var(--spacing-sm) var(--spacing-lg);
    color: var(--text-light);
    font-size: 1.05rem;
    transition: background-color var(--transition-speed) ease, color var(--transition-speed) ease;
    border-left: 4px solid transparent;
}

.sidebar-nav .nav-link:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--accent-gold);
    text-decoration: none;
    border-left-color: var(--accent-gold);
}
.sidebar-nav .nav-link.active {
    background-color: rgba(255, 255, 255, 0.15);
    border-left-color: var(--accent-gold);
    color: var(--accent-gold);
    font-weight: 600;
}


.close-sidebar-btn {
    background: none;
    border: none;
    color: var(--text-light);
    font-size: 1.8rem;
    cursor: pointer;
    padding: var(--spacing-xs); /* Use new smaller spacing */
    line-height: 1;
    opacity: 0.8;
    transition: opacity var(--transition-speed) ease, transform var(--transition-speed) ease;
}

.close-sidebar-btn:hover {
    opacity: 1;
    transform: rotate(90deg);
}

/* Content Wrapper (main content area) */
#content-wrapper {
    flex-grow: 1;
    width: 100%; /* Take full width on small screens */
    min-width: 0;
    background-color: var(--background-grey);
    display: flex;
    flex-direction: column;
}

/* Top Navigation Bar */
.top-navbar {
    background-color: var(--background-light);
    padding: var(--spacing-sm) var(--spacing-lg);
    border-bottom: 1px solid var(--border-color);
    margin-bottom: var(--spacing-lg);
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    min-height: 15px;
    display: flex;
    align-items: center;
    position: relative;
    z-index: 100;
}

.menu-toggle-btn {
    background-color: var(--accent-gold);
    border: none;
    padding: var(--spacing-xs);
    border-radius: var(--border-radius);
    cursor: pointer;
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    width: 40px;
    height: 30px;
    position: relative;
    z-index: 10;
    transition: background-color var(--transition-speed) ease;
}

.menu-toggle-btn:hover {
    background-color: #e5c84a;
}

.hamburger-icon {
    display: block;
    width: 100%;
    height: 4px;
    background-color: var(--primary-dark);
    border-radius: 2px;
    transition: all var(--transition-speed) ease-in-out;
}

.hamburger-icon:not(:last-child) {
    margin-bottom: 4px;
}

/* Toggled State for Sidebar (when active/shown) */
#wrapper.toggled .sidebar {
    transform: translateX(0);
}

/* Backdrop for mobile sidebar */
#wrapper.toggled::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.6);
    z-index: 1025;
    display: block;
    backdrop-filter: blur(2px);
}


/* General Content Area Padding (consistent with --spacing-lg) */
.container-fluid {
    width: 100%;
    padding-right: var(--spacing-lg);
    padding-left: var(--spacing-lg);
    margin-right: auto;
    margin-left: auto;
}


.row {
    display: flex;
    flex-wrap: wrap;
    margin-left: calc(-1 * var(--spacing-lg) / 2);
    margin-right: calc(-1 * var(--spacing-lg) / 2);
}

/* Columns - Mobile First (default to full width) */
.col-12 {
    flex: 0 0 100%;
    max-width: 100%;
    padding-left: calc(var(--spacing-lg) / 2);
    padding-right: calc(var(--spacing-lg) / 2);
    margin-bottom: var(--spacing-lg);
}
/* By default, all columns are 100% width on small screens.
   Specific column widths like col-md-6, col-lg-3 will be defined in media queries. */


/* Card Styles */
.card {
    background-color: var(--background-light);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: 0 4px 18px rgba(0, 0, 0, 0.08);
    margin-bottom: 0; /* Managed by column margin-bottom */
    overflow: hidden;
    height: 100%;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 22px rgba(0, 0, 0, 0.12);
}

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

.card-title {
    font-size: 1.3rem;
    margin-bottom: var(--spacing-sm);
    color: var(--primary-dark);
}

.card-text {
    font-size: 1.1rem;
}

.fs-4 {
    font-size: 1.6rem !important;
    font-weight: bold;
    color: var(--accent-gold);
}

/* Table Styles */
.table {
    width: 100%;
    margin-bottom: var(--spacing-lg);
    color: var(--text-dark);
    border-collapse: collapse;
    border-radius: var(--border-radius);
    overflow: hidden;
}

.table th,
.table td {
    padding: var(--spacing-md);
    vertical-align: middle;
    border-top: 1px solid var(--border-color);
}

.table thead th {
    vertical-align: bottom;
    border-bottom: 2px solid var(--border-color);
    background-color: var(--background-grey);
    font-weight: 700;
    color: var(--primary-dark);
    text-align: left;
}

.table-striped tbody tr:nth-of-type(odd) {
    background-color: var(--hover-bg);
}
.table-striped tbody tr:hover {
    background-color: rgba(0, 0, 0, 0.08);
}


/* Badge Styles */
.badge {
    display: inline-block;
    padding: 0.4em 0.8em;
    font-size: 0.8em;
    font-weight: 700;
    line-height: 1;
    text-align: center;
    white-space: nowrap;
    vertical-align: middle;
    border-radius: 0.4rem;
    color: var(--text-light);
}

.badge-success { background-color: #27ae60; }
.badge-danger { background-color: #e74c3c; }


/* Footer Styles */
.footer {
    background-color: var(--primary-dark);
    color: var(--text-light);
    padding: var(--spacing-lg) 0;
    text-align: center;
    width: 100%;
    margin-top: auto;
    box-shadow: 0 -2px 8px rgba(0,0,0,0.08);
}

.footer p {
    margin: 0;
    font-size: 0.95rem;
}

/* Login Page Styles (Externalized from index.php) */
body.login-body {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    font-family: 'Inter', 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    color: var(--text-dark);
    font-size: var(--spacing-md);
}

.login-container {
    width: 100%;
    max-width: 400px;
    padding: var(--spacing-lg);
    box-sizing: border-box;
}

.login-card {
    background-color: var(--background-light);
    border-radius: var(--border-radius);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.1);
    padding: var(--spacing-xl);
    text-align: center;
}

.login-title {
    color: var(--primary-dark);
    margin-bottom: var(--spacing-lg);
    font-size: 2rem;
    font-weight: 700;
}

.login-form .form-group {
    margin-bottom: var(--spacing-md);
}

.login-form .form-control {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: var(--spacing-md);
    transition: border-color var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
    box-sizing: border-box;
}

.login-form .form-control:focus {
    border-color: var(--accent-gold);
    box-shadow: 0 0 0 0.2rem rgba(243, 156, 18, 0.25);
    outline: none;
}

.login-button {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-lg);
    background-color: var(--primary-dark);
    color: var(--text-light);
    border: none;
    border-radius: var(--border-radius);
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color var(--transition-speed) ease, transform 0.1s ease;
}

.login-button:hover {
    background-color: var(--accent-gold);
    transform: translateY(-2px);
}

.alert {
    padding: var(--spacing-sm) var(--spacing-md);
    margin-bottom: var(--spacing-md);
    border: 1px solid transparent;
    border-radius: var(--border-radius);
    color: #721c24;
    background-color: #f8d7da;
    border-color: #f5c6cb;
    text-align: left;
    font-size: var(--spacing-md);
}


/* Media Queries - Progressive Enhancement */

/* Small devices (landscape phones, 576px and up) */
@media (min-width: 576px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.6rem; }
    .col-md-6 {
        flex: 0 0 50%;
        max-width: 50%;
    }
}

/* Medium devices (tablets, 768px and up) */
@media (min-width: 768px) {
    /* Desktop layout for sidebar and content */
    #wrapper {
        flex-direction: row; /* Sidebar and content side-by-side */
    }

    .sidebar {
        position: fixed; /* Make it fixed on desktop */
        transform: translateX(0); /* Always visible */
        box-shadow: none; /* No overlay shadow */
        height: 100vh; /* Fill full viewport height */
        top: 0;
        left: 0;
        z-index: 1020; /* Ensure it stays above content */
    }

    #content-wrapper {
        margin-left: var(--sidebar-width); /* Make space for fixed sidebar */
    }

    .menu-toggle-btn {
        display: none; /* Hide hamburger menu on desktop */
    }

    .close-sidebar-btn {
        display: none; /* Hide close button on desktop */
    }

    /* Toggled state on desktop (if we want to hide sidebar on desktop) */
    #wrapper.toggled .sidebar {
        transform: translateX(-100%); /* Allows hiding sidebar on desktop */
        position: fixed; /* Recovers fixed position when hidden */
    }
    #wrapper.toggled #content-wrapper {
        margin-left: 0; /* Content takes full width when sidebar hidden */
    }

    /* Column adjustments for medium devices */
    .col-lg-3 { /* Default to full width on mobile, 50% on small, 33.33% on medium, 25% on large */
        flex: 0 0 33.333333%;
        max-width: 33.333333%;
    }
    .col-md-6 {
        flex: 0 0 50%;
        max-width: 50%;
    }
}

/* Large devices (desktops, 992px and up) */
@media (min-width: 992px) {
    h1 { font-size: 2.5rem; }
    h2 { font-size: 2rem; }
    .col-lg-3 {
        flex: 0 0 25%;
        max-width: 25%;
    }
}

/* Extra large devices (large desktops, 1200px and up) */
@media (min-width: 1200px) {
    /* Further refinements for extra large screens */
}