body { 
    font-family: 'Roboto', sans-serif; 
    background: #f4f6f9; 
    overflow-x: hidden; 
}

/* Sidebar */
.sidebar { 
    width: 250px; 
    height: 100vh; 
    background: #1e3a4f; 
    position: fixed; 
    left: 0; 
    top: 0; 
    color: #fff; 
    transition: all 0.3s;
    z-index: 1040;
}
.sidebar .logo { 
    text-align: center; 
    font-size: 22px; 
    font-weight: bold; 
    padding: 15px 0; 
    border-bottom: 1px solid #2d4f63; 
    margin-bottom: 10px; 
}
.sidebar .logo i { 
    color: #17a2b8; 
    margin-right: 8px; 
}
.sidebar .nav-link { 
    color: #ccc; 
    padding: 12px 20px; 
    font-size: 14px; 
    border-left: 3px solid transparent; 
}
.sidebar .nav-link:hover, .sidebar .nav-link.active { 
    background: #162b39; 
    color: #fff; 
    border-left-color: #17a2b8; 
}
.sidebar .nav-link i { 
    margin-right: 10px; 
    width: 20px; 
    text-align: center; 
}

/* Layout chính */
.main-wrapper { 
    margin-left: 250px; 
    transition: all 0.3s;
}

/* Topbar chứa thông tin User */
.topbar {
    background: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
    padding: 10px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.content-padding { 
    padding: 20px; 
}

/* Card Thống kê */
.card-stat { 
    border-radius: 8px; 
    border: none; 
    box-shadow: 0 2px 6px rgba(0,0,0,0.05); 
}
.card-stat .icon { 
    font-size: 28px; 
}

/* Responsive cho màn hình nhỏ (Tablet/Mobile) */
@media (max-width: 768px) {
    .sidebar { 
        margin-left: -250px; 
    }
    .sidebar.active { 
        margin-left: 0; 
    }
    .main-wrapper { 
        margin-left: 0; 
    }
}