:root {
    --primary-bg: #1f2937;
    --secondary-bg: #f9fafb;
    --card-bg: #fff;
    --accent-color: #6366f1;
    --accent-color-hover: #4f46e5;
    --accent-gradient: linear-gradient(to right, #6366f1, #818cf8);
    --text-color: #111827;
    --text-light-color: #6b7280;
    --border-color: #e5e7eb;
    --sidebar-width: 280px;
    --card-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --card-hover-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --border-radius-lg: 16px;
    --border-radius-md: 10px;
    --transition-fast: all 0.2s ease-in-out;
}

body[data-theme="dark"] {
    --secondary-bg: #111827;
    --card-bg: #1f2937;
    --text-color: #f9fafb;
    --text-light-color: #9ca3af;
    --border-color: #374151;
}

body {
    font-family: 'Inter', sans-serif;
    margin: 0;
    background-color: var(--secondary-bg);
    color: var(--text-color);
    display: flex;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    background-image: radial-gradient(circle at 1px 1px, #e5e7eb 1px, transparent 0);
    background-size: 25px 25px;
    transition: background-color 0.3s, color 0.3s;
}

body[data-theme="dark"] {
    background-image: radial-gradient(circle at 1px 1px, #374151 1px, transparent 0);
}

.sidebar {
    width: var(--sidebar-width);
    background-color: var(--primary-bg);
    color: #e5e7eb;
    position: fixed;
    height: 100%;
    overflow-y: auto;
    border-right: 1px solid #374151;
    transition: width 0.3s ease;
}

.sidebar-header {
    padding: 32px;
    text-align: center;
    font-size: 1.75rem;
    font-weight: 800;
    letter-spacing: 1px;
    border-bottom: 1px solid #374151;
    color: white;
}

.sidebar-nav ul {
    list-style: none;
    padding: 0;
    margin: 20px 0;
}

.sidebar-nav ul li a {
    color: #a1a1aa;
    text-decoration: none;
    display: flex;
    align-items: center;
    padding: 16px 30px;
    margin: 8px 15px;
    border-radius: var(--border-radius-md);
    transition: var(--transition-fast);
    font-weight: 600;
}

.sidebar-nav ul li a .icon {
    margin-right: 20px;
    font-size: 1.25rem;
    width: 25px;
    text-align: center;
    color: #71717a;
    transition: var(--transition-fast);
}

.sidebar-nav ul li a:hover {
    background-color: #374151;
    color: white;
}

.sidebar-nav ul li a:hover .icon {
    color: white;
    transform: scale(1.1);
}

.sidebar-nav ul li a.active {
    background: var(--accent-gradient);
    color: white;
    box-shadow: 0 4px 10px rgba(79, 70, 229, 0.3);
}

.sidebar-nav ul li a.active .icon {
    color: white;
}

.main-content {
    margin-left: var(--sidebar-width);
    flex-grow: 1;
    padding: 50px;
    transition: margin-left 0.3s ease;
}

.page {
    display: none;
    animation: fadeIn 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.page.active {
    display: block;
}

.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 40px;
}

.header h1 {
    margin: 0;
    font-size: 2.5rem;
    font-weight: 800;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 20px;
}

.theme-toggle {
    background: none;
    border: 1px solid var(--border-color);
    font-size: 1.25rem;
    cursor: pointer;
    color: var(--text-light-color);
    padding: 8px;
    border-radius: var(--border-radius-md);
    width: 44px;
    height: 44px;
    display: flex;
    justify-content: center;
    align-items: center;
    transition: var(--transition-fast);
}

.theme-toggle:hover {
    background-color: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.user-profile {
    display: flex;
    align-items: center;
    font-weight: 600;
    background: var(--card-bg);
    padding: 8px 16px;
    border-radius: 30px;
    box-shadow: var(--card-shadow);
    border: 1px solid var(--border-color);
}

.user-profile img {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    margin-left: 15px;
}

.card {
    background-color: var(--card-bg);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--card-shadow);
    padding: 32px;
    margin-bottom: 32px;
    transition: var(--transition-fast);
    border: 1px solid var(--border-color);
}

.card:hover {
    box-shadow: var(--card-hover-shadow);
    transform: translateY(-5px);
}

.card h2 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-top: 0;
    margin-bottom: 25px;
}

.chart-container {
    position: relative;
    height: 350px;
}

.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 32px;
}

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

.stat-card-info h3 {
    margin: 0;
    font-size: 2.5rem;
    font-weight: 700;
}

.stat-card-info p {
    margin: 5px 0 0;
    color: var(--text-light-color);
    font-size: 0.9rem;
}

.stat-card-icon {
    font-size: 2.5rem;
    color: var(--accent-color);
    background-color: #eef2ff;
    height: 70px;
    width: 70px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 25px;
    background-color: var(--card-bg);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    box-shadow: var(--card-shadow);
}

th, td {
    padding: 20px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition-fast);
}

th {
    background-color: var(--secondary-bg);
    font-weight: 600;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-light-color);
}

tbody tr:hover {
    background-color: var(--secondary-bg);
}

td:first-child, th:first-child {
    border-left: 4px solid transparent;
}

tbody tr:hover td:first-child {
    border-left: 4px solid var(--accent-color);
}

.action-btn {
    background: var(--accent-gradient);
    color: white;
    padding: 12px 24px;
    border: none;
    border-radius: var(--border-radius-md);
    cursor: pointer;
    font-weight: 600;
    font-size: 0.95rem;
    transition: var(--transition-fast);
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    background-size: 200% auto;
}

.action-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 7px 10px rgba(0,0,0,0.1);
    background-position: right center;
}

.action-btn:active {
    transform: translateY(0);
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

/* Button Modifiers */
.action-btn.btn-green {
    background: linear-gradient(to right, #28a745, #2dc253);
    background-size: 200% auto;
}

.action-btn.btn-info {
    background: linear-gradient(to right, #17a2b8, #1bc5e0);
    background-size: 200% auto;
}

.action-btn.btn-danger {
    background: linear-gradient(to right, #dc3545, #e45765);
    background-size: 200% auto;
}

.settings-form {
    max-width: 600px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    font-size: 0.9rem;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 12px 16px;
    height: 52px;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-md);
    box-sizing: border-box;
    transition: var(--transition-fast);
    background-color: var(--secondary-bg);
    font-size: 1rem;
    color: var(--text-color);
}

.form-group input[type="color"] {
    padding: 5px;
    height: 52px;
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
    background-color: var(--card-bg);
}