/* Header banner image shown at the top of each Newton Fundamentals lesson. */
img.lesson-header {
    display: block;
    width: 100%;
    max-width: 720px;
    margin: 0.5rem auto 1.75rem auto;
    border-radius: 10px;
    border: 1px solid var(--pst-color-border, #d0d7de);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
    background: #ffffff;
}