:root {
    --sidebar-width: 280px;
    --primary-color: #4f46e5;
    --primary-hover: #4338ca;
    --bg-color: #f9fafb;
    --sidebar-bg: #111827;
}

body { 
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: #111827;
    display: flex;
    min-height: 100vh;
}

#sidebar { 
    width: var(--sidebar-width);
    background: var(--sidebar-bg);
    color: white;
    flex-shrink: 0;
    display: flex;
    flex-direction: column;
    transition: all 0.3s;
    box-shadow: 4px 0 10px rgba(0,0,0,0.05);
}

.sidebar-header {
    padding: 2rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 12px;
}

.sidebar-header i {
    font-size: 1.5rem;
    color: var(--primary-color);
}

.sidebar-header h4 {
    margin: 0;
    font-weight: 700;
    letter-spacing: -0.5px;
}

#sidebar a { 
    color: #9ca3af;
    text-decoration: none;
    padding: 0.75rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 500;
    transition: all 0.2s;
    border-left: 4px solid transparent;
}

#sidebar a i {
    width: 20px;
    text-align: center;
}

#sidebar a:hover { 
    background: #1f2937;
    color: white;
}

#sidebar a.active { 
    background: #1f2937;
    color: white;
    border-left-color: var(--primary-color);
}

#content { 
    flex-grow: 1;
    padding: 2.5rem;
    overflow-y: auto;
}

.card { 
    border: none;
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-primary {
    background-color: var(--primary-color);
    border-color: var(--primary-color);
    font-weight: 600;
    padding: 0.6rem 1.2rem;
    border-radius: 8px;
}

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

.page-title {
    font-weight: 800;
    letter-spacing: -1px;
    margin-bottom: 2rem;
    color: #111827;
}

/* Custom Scrollbar */
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: #f1f1f1; }
::-webkit-scrollbar-thumb { background: #d1d5db; border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: #9ca3af; }