/* =========================================================
   CSS RESET + BASE
========================================================= */
* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: system-ui, -apple-system, BlinkMacSystemFont,
                 "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell,
                 "Open Sans", "Helvetica Neue", sans-serif;

    background: var(--bg);
    color: var(--text);
    transition: background-color 0.35s ease, color 0.35s ease;
}

/* =========================================================
   THEME VARIABLES
========================================================= */
:root {
    /* Core */
    --bg: #f8fafc;
    --card: #ffffff;
    --text: #0f172a;
    --muted-text: #64748b;
    --border: #cbd5e1;

    /* Sidebar */
    --sidebar-bg: #020617;
    --sidebar-text: #e5e7eb;
    --sidebar-hover: #1e293b;
    --sidebar-active: #2563eb;

    /* Tables */
    --table-bg: #ffffff;
    --table-header-bg: #2563eb;
    --table-header-text: #ffffff;
    --row-odd: #f1f5f9;
    --row-even: #e5e7eb;
    --row-hover: #c7d2fe;

    /* Buttons */
    --primary: #2563eb;
    --primary-hover: #1e40af;
    --secondary: #64748b;
    --secondary-hover: #475569;
    --success: #16a34a;
    --success-hover: #15803d;
    --danger: #dc2626;
    --danger-hover: #b91c1c;

    /* Inputs */
    --input-bg: #f8fafc;
    --input-text: #0f172a;
    --input-border: #cbd5e1;
    --input-focus: #2563eb;
}

/* ================= DARK MODE ================= */
body.dark {
    --bg: #0f172a;
    --card: #020617;
    --text: #e5e7eb;
    --muted-text: #94a3b8;
    --border: #334155;

    --sidebar-bg: #020617;
    --sidebar-text: #e5e7eb;
    --sidebar-hover: #1e293b;
    --sidebar-active: #3b82f6;

    --table-bg: #020617;
    --table-header-bg: #3b82f6;
    --table-header-text: #ffffff;
    --row-odd: #020617;
    --row-even: #020617;
    --row-hover: #1e293b;

    --input-bg: #020617;
    --input-text: #e5e7eb;
    --input-border: #334155;
    --input-focus: #3b82f6;
}

/* =========================================================
   SIDEBAR
========================================================= */
.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: 180px;
    height: 100vh;
    background: var(--sidebar-bg);
    display: flex;
    flex-direction: column;
    transition: background-color 0.35s ease;
}

.sidebar #sidebar-ERP-title {
    color: var(--sidebar-text);
    padding: 16px;
    margin: 0;
    font-size: 18px;
    border-bottom: 1px solid var(--border);
}

.sidebar a {
    margin: 4px 8px;
    padding: 12px 16px;
    border-radius: 8px;

    color: var(--sidebar-text);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;

    transition: all 0.25s ease;
}

.sidebar a:hover {
    background: var(--sidebar-hover);
    transform: translateX(4px);
}

.sidebar a.active {
    background: var(--sidebar-active);
    color: #fff;
    box-shadow: 0 4px 10px rgba(37, 99, 235, 0.35);
}

/* =========================================================
   CONTENT
========================================================= */
.content {
    margin-left: 200px;
    padding: 5%;
    transition: background-color 0.35s ease;
}

/* =========================================================
   TABLES
========================================================= */
table {
    width: 100%;
    margin-top: 20px;
    border-collapse: separate;
    border-spacing: 0;

    background: var(--table-bg);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}

table th {
    background: var(--table-header-bg);
    color: var(--table-header-text);
    padding: 12px 14px;
    text-align: left;
    font-weight: 600;
}

table td {
    padding: 10px 14px;
    border-bottom: 1px solid var(--border);
}

table tbody tr:nth-child(odd) {
    background: var(--row-odd);
}

table tbody tr:nth-child(even) {
    background: var(--row-even);
}

table tbody tr:hover {
    background: var(--row-hover);
    transition: background-color 0.2s ease;
}

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

/* =========================================================
   BUTTONS
========================================================= */
button,
.btn {
    padding: 10px 16px;
    font-size: 14px;
    font-weight: 600;

    border-radius: 8px;
    border: none;
    cursor: pointer;

    transition: all 0.2s ease;
}

/* Primary */
.btn-primary,
button[type="submit"] {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 4px 10px rgba(37,99,235,0.35);
}

.btn-primary:hover,
button[type="submit"]:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
}

/* Secondary */
.btn-secondary {
    background: var(--secondary);
    color: #fff;
}

.btn-secondary:hover {
    background: var(--secondary-hover);
}

/* Success */
.btn-success {
    background: var(--success);
    color: #fff;
}

.btn-success:hover {
    background: var(--success-hover);
}

/* Danger */
.btn-danger {
    background: var(--danger);
    color: #fff;
}

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

/* Disabled */
button:disabled {
    background: var(--border);
    color: var(--muted-text);
    cursor: not-allowed;
}

/* =========================================================
   INPUTS / SEARCH
========================================================= */
input,
select {
    padding: 10px 14px;
    border-radius: 8px;
    border: 1px solid var(--input-border);
    background: var(--input-bg);
    color: var(--input-text);
    font-size: 14px;

    transition: all 0.25s ease;
}

input::placeholder {
    color: var(--muted-text);
}

input:focus,
select:focus {
    outline: none;
    border-color: var(--input-focus);
    box-shadow: 0 0 0 3px rgba(59,130,246,0.25);
}

/* Search input helper */
.search-input {
    width: 280px;
}

/* =========================================================
   BUTTON GROUPS
========================================================= */
.button-group {
    margin-top: 16px;
    display: flex;
    gap: 10px;
}

.table-wrapper {
    width: 100%;
    overflow-x: auto;
}

table {
    width: 100%;
    min-width: 900px; /* prevents button columns collapsing */
}

.app-container {
    display: flex;
    height: 100vh;
    overflow: hidden;
}

/* Sidebar */
.sidebar {
    width: 220px;
    flex-shrink: 0;
    overflow-y: auto;
}

/* Main page content */
main {
    flex: 1;
    padding: 20px;
    overflow-y: auto;
}