:root {
    --bg-color: #0f172a;
    --sidebar-bg: #1e293b;
    --card-bg: rgba(30, 41, 59, 0.7);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-color: #38bdf8;
    --accent-hover: #0284c7;
    --border-color: rgba(255, 255, 255, 0.1);
    --input-bg: rgba(15, 23, 42, 0.6);
}


/* =========================================
   Base & Reset
   ========================================= */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    /* FLEXBOX LAYOUT ENGINE */
    display: flex;
    overflow-x: hidden;
    background-image:
        radial-gradient(at 0% 0%, rgba(56, 189, 248, 0.1) 0, transparent 50%),
        radial-gradient(at 100% 100%, rgba(139, 92, 246, 0.1) 0, transparent 50%);
    background-attachment: fixed;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    color: var(--text-primary);
    font-weight: 700;
    letter-spacing: -0.025em;
    margin-bottom: 1.5rem;
}

a {
    text-decoration: none;
    color: inherit;
    transition: 0.3s;
}

ul {
    list-style: none;
    padding: 0;
}

/* =========================================
   Sidebar & Layout (Desktop)
   ========================================= */
@media (min-width: 992px) {
    .sidebar {
        width: 260px;
        height: 100vh;
        position: sticky;
        top: 0;
        z-index: 1020;
        background: var(--sidebar-bg);
        border-right: 1px solid var(--border-color);
        /* Ensure it displays as a column always on desktop */
        display: flex !important;
        flex-direction: column;
        flex-shrink: 0;
        overflow-y: auto;
        transition: margin-left 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        visibility: visible !important;
        transform: none !important;
    }

    /* Collapsed State: Negative margin pulls it off-screen */
    body.sidebar-collapsed .sidebar {
        margin-left: -260px;
    }
}

/* =========================================
   Main Content Area
   ========================================= */
.main-content {
    flex-grow: 1;
    padding: 2rem;
    width: 100%;
    /* Forces it to fill available flex space */
    /* CENTER THE CONTENT */
    max-width: 1600px;
    /* Professional constraint */
    margin-inline: auto;

    display: flex;
    flex-direction: column;
    /* Note: We don't use align-items: center here because we want full-width cards */
    /* But the max-width + margin-inline: auto handles the centering of the block itself */
}

/* Mobile Adjustments */
@media (max-width: 991.98px) {
    .main-content {
        padding: 1rem;
        max-width: 100%;
    }
}

/* =========================================
   Components (Cards, Forms, Tables)
   ========================================= */
.card {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    padding: 2rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    margin-bottom: 2rem;
    width: 100%;
}

.form-group {
    margin-bottom: 1.25rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

input,
select,
textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    background: var(--input-bg);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    color: var(--text-primary);
    font-size: 1rem;
    transition: all 0.2s;
}

input:focus,
select:focus,
textarea:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 2px rgba(56, 189, 248, 0.2);
}

button[type="submit"],
.btn-primary {
    width: 100%;
    padding: 0.875rem;
    background: var(--accent-color);
    color: white;
    border: none;
    border-radius: 0.5rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s;
}

button:hover,
.btn-primary:hover {
    background-color: var(--accent-hover);
}

/* Sidebar Links */
.nav-link {
    color: var(--text-secondary);
    padding: 0.75rem 1rem;
    border-radius: 0.5rem;
    margin-bottom: 0.25rem;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.nav-link:hover,
.nav-link.active {
    background: rgba(56, 189, 248, 0.1);
    color: var(--accent-color);
}

.nav-link i {
    width: 20px;
    text-align: center;
}

/* Submenu/Dropdown */
.dropdown-btn {
    width: 100%;
    background: transparent;
    border: none;
    justify-content: space-between;
    cursor: pointer;
    text-align: left;
}

.dropdown-container {
    padding-left: 1.5rem;
    display: none;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 0.5rem;
    margin-bottom: 0.5rem;
}

.dropdown-container.show {
    display: block;
    padding-top: 0.5rem;
    padding-bottom: 0.5rem;
}

/* Inventory Table */
.inventory-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
}

.inventory-table th,
.inventory-table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.inventory-table th {
    color: var(--text-primary);
    font-weight: 600;
}

.inventory-table tr:hover td {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.02);
}

/* Status Messages */
.status-msg {
    margin-top: 1rem;
    padding: 1rem;
    border-radius: 0.5rem;
    background: rgba(16, 185, 129, 0.2);
    color: #34d399;
    border: 1px solid rgba(16, 185, 129, 0.3);
    display: none;
}

/* Modal */
.modal-content {
    background-color: var(--sidebar-bg);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.close {
    color: var(--text-secondary);
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close:hover {
    color: var(--accent-color);
}

/* =========================================
   DataTables Dark Mode Overrides
   ========================================= */
.dataTables_wrapper {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

table.dataTable {
    color: var(--text-primary) !important;
    border-bottom: 1px solid var(--border-color) !important;
}

table.dataTable th,
table.dataTable td {
    border-color: var(--border-color) !important;
}

table.dataTable thead th {
    color: var(--text-primary);
    border-bottom: 2px solid var(--border-color) !important;
}

/* Input Search & Length filters */
.dataTables_filter input,
.dataTables_length select {
    background: var(--input-bg) !important;
    border: 1px solid var(--border-color) !important;
    color: var(--text-primary) !important;
    border-radius: 0.5rem;
    padding: 0.3rem 0.5rem;
}

/* Pagination Buttons */
.dataTables_wrapper .dataTables_paginate .paginate_button {
    color: var(--text-secondary) !important;
}

.dataTables_wrapper .dataTables_paginate .paginate_button.current,
.dataTables_wrapper .dataTables_paginate .paginate_button.current:hover {
    background: var(--accent-color) !important;
    color: white !important;
    border: none;
    border-radius: 0.3rem;
}

.dataTables_wrapper .dataTables_paginate .paginate_button:hover {
    background: rgba(255, 255, 255, 0.1) !important;
    color: white !important;
    border: none;
}