Here's a CSS snippet that demonstrates how to create a responsive layout for a post container and a sidebar that automatically adjusts to the screen size. This example uses Flexbox for layout management. css /* Main container for the layout / .container { display: flex; flex-wrap: wrap; / Allows items to wrap onto the next line if there's not enough space / margin: 0 auto; / Centering the container / max-width: 1200px; / Maximum width of the container */ } /* Post container styles / .post-container { flex: 1 1 70%; / Grow to fill available space, base size of 70% / min-width: 300px; / Minimum width to maintain readability / padding: 20px; / Spacing inside the post container / box-sizing: border-box; / Include padding in width calculations */ } /* Sidebar styles / .sidebar { flex: 1 1 30%; / Grow to fill available space, base size of 30% / min-width: 250px; / Minimum width for the sidebar / padding: 20px; / Spacing inside the sidebar / box-sizing: border-box; / Include padding in width calculations */ } /* Responsive adjustments / @media (max-width: 768px) { .post-container, .sidebar { flex: 1 1 100%; / Full width on smaller screens */ } } This code will ensure that the post container takes up 70% of the available width while the sidebar takes 30%. On screens narrower than 768px, both sections will stack vertically, each taking 100% of the width.