:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --bg-color: #f3f4f6;
    --surface-color: #ffffff;
    --text-color: #1f2937;
    --text-light: #6b7280;
    --border-color: #e5e7eb;
    --danger-color: #ef4444;
    --success-color: #10b981;
}

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

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.5;
}

.layout-container {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 250px;
    background-color: var(--surface-color);
    border-right: 1px solid var(--border-color);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
}

.sidebar-header {
    margin-bottom: 2rem;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-color);
}

.nav-link {
    display: block;
    padding: 0.75rem 1rem;
    text-decoration: none;
    color: var(--text-color);
    border-radius: 0.375rem;
    margin-bottom: 0.5rem;
    transition: background-color 0.2s;
}

.nav-link:hover, .nav-link.active {
    background-color: var(--bg-color);
    color: var(--primary-color);
    font-weight: 500;
}

.nav-link.logout {
    margin-top: auto;
    color: var(--danger-color);
}

.nav-link.logout:hover {
    background-color: #fee2e2;
}

/* Main Content */
.main-content {
    flex: 1;
    padding: 2rem;
    overflow-y: auto;
}

.header {
    margin-bottom: 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.page-title {
    font-size: 1.875rem;
    font-weight: 700;
}

/* Cards */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.card {
    background-color: var(--surface-color);
    padding: 1.5rem;
    border-radius: 0.75rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    border: 1px solid var(--border-color);
}

.card-title {
    font-size: 0.875rem;
    color: var(--text-light);
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.card-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-color);
}

/* Auth Pages */
.auth-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-color: var(--bg-color);
}

.auth-box {
    background-color: var(--surface-color);
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    width: 100%;
    max-width: 400px;
}

.form-group {
    margin-bottom: 1rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.form-input {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 0.375rem;
    font-size: 1rem;
}

.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 0.375rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    width: 100%;
    text-align: center;
    text-decoration: none;
}

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