:root {
    --primary: #4F46E5; /* Indigo Theme */
    --primary-hover: #4338CA;
    --secondary: #E0E7FF;
    --secondary-hover: #C7D2FE;
    --text-dark: #111827;
    --text-muted: #4B5563;
    --bg-main: #F3F4F6;
    --bg-card: #FFFFFF;
    --border-color: #E5E7EB;
    --danger: #EF4444;
    --danger-hover: #DC2626;
    --success: #10B981;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: var(--bg-main);
    color: var(--text-dark);
    min-height: 100vh;
}

:root {
    --header: #FFFFFF;
    --background: #F3F4F6;
    --text: #111827;
    --muted: #4B5563;
    --card: #FFFFFF;
    --border: #E5E7EB;
}

html.dark {
    --header: #1F2937;
    --background: #0F172A;
    --text: #E5E7EB;
    --muted: #A1A1AA;
    --card: #111827;
    --border: #334155;
}

body {
    background-color: var(--background);
    color: var(--text);
    min-height: 100vh;
}

.stat-card {
    background-color: var(--card);
    border: 1px solid var(--border);
    padding: 1rem 1.2rem;
    border-radius: 12px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.05);
    text-align: center;
    min-width: 160px;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit,minmax(160px,1fr));
    gap: 1rem;
    margin-top: 1.5rem;
}

.stat-card h3 {
    font-size: 0.9rem;
    color: var(--muted);
    font-weight: 600;
    margin-bottom: 0.35rem;
}

.stat-card p {
    font-size: 1.7rem;
    font-weight: 800;
    margin: 0;
}

.view-actions {
    display: flex;
    gap: 0.65rem;
}

.btn + .btn { min-width: 112px; }

.navbar, .card { background-color: var(--card); }

@media (max-width: 820px) {
    .nav-container { flex-wrap: wrap; height: auto; padding: 0.75rem 1rem; }
    .nav-links { width: 100%; justify-content: center; gap: 0.8rem; margin-top: 0.6rem; }
    .hero { padding: 3.5rem 1rem; }
    .hero h1 { font-size: 2.1rem; }
    .main-content { margin: 1.5rem auto; padding: 0 1rem; }
    .card { padding: 1.25rem; }
    .data-table th, .data-table td { padding: 0.8rem 0.75rem; }
}

/* Navbar */
.navbar {
    background-color: var(--bg-card);
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-brand {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.nav-links {
    display: flex;
    gap: 1.5rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-muted);
    font-weight: 500;
    padding: 0.5rem 0.75rem;
    border-radius: 6px;
    transition: all 0.2s;
}

.nav-link:hover {
    color: var(--primary);
    background-color: var(--secondary);
}

.nav-link.active {
    color: var(--primary);
    font-weight: 600;
    background-color: var(--secondary);
}

/* Main Content */
.main-content {
    max-width: 1200px;
    margin: 3rem auto;
    padding: 0 2rem;
}

/* Page visibility */
.page {
    display: none;
    animation: fadeIn 0.4s ease-out;
}

.page.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Home Page */
.hero {
    text-align: center;
    padding: 6rem 2rem;
    background-color: var(--bg-card);
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgba(0,0,0,0.05);
}

.hero h1 {
    font-size: 3rem;
    font-weight: 800;
    color: var(--text-dark);
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 2.5rem;
}

.hero-actions {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.6rem 1.25rem;
    font-weight: 500;
    border-radius: 6px;
    border: none;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 0.95rem;
    text-decoration: none;
}

.btn-large {
    padding: 0.8rem 1.75rem;
    font-size: 1.1rem;
}

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

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

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

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

.btn-outline {
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-muted);
}

.btn-outline:hover {
    border-color: var(--text-muted);
    color: var(--text-dark);
    background-color: #F9FAFB;
}

.btn-danger {
    background-color: #FEE2E2;
    color: var(--danger);
}

.btn-danger:hover {
    background-color: #FECACA;
}

/* Forms & Cards */
.page-header {
    margin-bottom: 2rem;
}

.page-header h2 {
    font-size: 1.8rem;
    color: var(--text-dark);
}

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

.card {
    background-color: var(--bg-card);
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgba(0,0,0,0.05);
    padding: 2.5rem;
}

.form-card {
    max-width: 600px;
    margin: 0 auto;
}

.input-group {
    margin-bottom: 1.5rem;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-dark);
}

.input-group input {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
    background-color: #FAFAFA;
}

.input-group input:focus {
    border-color: var(--primary);
    background-color: #FFFFFF;
    box-shadow: 0 0 0 3px var(--secondary);
}

.search-container {
    display: flex;
    align-items: center;
    max-width: 480px;
    margin: 0 auto 1.2rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: #FFFFFF;
    padding: 0.35rem 0.6rem;
    box-shadow: 0 1px 2px rgba(0,0,0,0.05);
}

.search-container input {
    width: 100%;
    border: none;
    outline: none;
    font-size: 0.95rem;
    background: transparent;
    padding: 0.5rem 0.25rem;
}

.search-container i {
    color: var(--text-muted);
    margin-left: 0.4rem;
}

.toast {
    position: fixed;
    right: 1.25rem;
    bottom: 1.25rem;
    background-color: #222;
    color: #fff;
    padding: 0.8rem 1.1rem;
    border-radius: 10px;
    opacity: 0;
    transform: translateY(15px);
    pointer-events: none;
    transition: opacity 0.25s ease, transform 0.25s ease;
    z-index: 999;
    box-shadow: 0 6px 12px rgba(0,0,0,0.22);
}

.toast.show {
    opacity: 0.95;
    transform: translateY(0);
}

.toast.success { background-color: #10B981; }
.toast.error { background-color: #EF4444; }

.site-footer {
    background-color: var(--card);
    border-top: 1px solid var(--border);
    color: var(--muted);
    text-align: center;
    padding: 0.8rem 0.75rem;
    margin-top: 2.5rem;
    font-size: 0.92rem;
}

.site-footer p {
    margin: 0;
}

.empty-state {
    text-align: center;
    color: var(--text-muted);
    font-style: italic;
    padding: 1.5rem;
}

.form-actions {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
}

/* Table */
.table-card {
    padding: 0;
    overflow: hidden;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
}

.data-table th, .data-table td {
    padding: 1rem 1.5rem;
}

.data-table th {
    background-color: #F9FAFB;
    font-weight: 600;
    color: var(--text-muted);
    border-bottom: 1px solid var(--border-color);
    text-transform: uppercase;
    font-size: 0.85rem;
    letter-spacing: 0.05em;
}

.data-table td {
    border-bottom: 1px solid var(--border-color);
    color: var(--text-dark);
}

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

.data-table tbody tr:hover {
    background-color: #F9FAFB;
}

.action-buttons {
    display: flex;
    gap: 0.5rem;
}

.action-buttons .btn {
    padding: 0.4rem 0.8rem;
    font-size: 0.85rem;
}

.empty-state {
    text-align: center;
    padding: 3rem;
    color: var(--text-muted);
}