/* ==== Reset & basic typography ==== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;600&display=swap');

*,
*::before,
*::after {
    box-sizing: border-box;
}
body {
    margin: 0;
    font-family: system-ui, sans-serif;
    line-height: 1.6;
    color: #222;
}

/* ==== Banner ==== */
.banner {
    background: #2c3e50;
    color: #fff;
    padding: 1rem;
    text-align: center;
}

/* ==== Navigation ==== */
.top-nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    background: #34495e;
}
.top-nav a {
    color: #ecf0f1;
    padding: 0.75rem 1rem;
    text-decoration: none;
}
.top-nav a:hover {
    background: #1abc9c;
}

/* ==== Layout grid ==== */
.layout {
    display: grid;
    grid-template-columns:
        minmax(200px, 250px)   /* left sidebar column */
        1fr                    /* main content column */
        minmax(150px, 200px)   /* right sidebar column */;
    gap: 1rem;
    padding: 1rem;
}

/* Left sidebars stack vertically */
.left-top,
.left-bottom {
    background: #f8f9fa;
    padding: 1rem;
}
.avatar {
    max-width: 100%;
    border-radius: 50%;
}

/* Main content */
.content {
    background: #fff;
    padding: 1.5rem;
    border: 1px solid #ddd;
}

/* Right sidebars – four equal boxes */
.right-1,
.right-2,
.right-3,
.right-4 {
    background: #f1f3f5;
    padding: 0.75rem;
    border: 1px solid #ccc;
}

/* ==== Footer ==== */
.footer {
    background: #2c3e50;
    color: #fff;
    text-align: center;
    padding: 0.5rem;
}

/* ==== Responsiveness ==== */

/* Tablet & small laptop */
@media (max-width: 1024px) {
    .layout {
        grid-template-columns:
            minmax(180px, 220px)   /* left */
            1fr                    /* main */
            minmax(120px, 160px);  /* right */
    }
}

/* Mobile portrait – collapse sidebars under the main content */
@media (max-width: 768px) {
    .layout {
        grid-template-columns: 1fr;          /* single column */
        grid-template-rows:
            auto   /* left‑top */
            auto   /* left‑bottom */
            auto   /* main content */
            auto   /* right‑1 */
            auto   /* right‑2 */
            auto   /* right‑3 */
            auto;  /* right‑4 */
    }

    .left-top,
    .left-bottom,
    .right-1,
    .right-2,
    .right-3,
    .right-4 {
        margin-bottom: 1rem;
    }
}