/* ───── base style for the three bars ───── */
.navbar {
    background: #181f2d;
    padding: 2rem;
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-links {
    display: flex;
    gap: 2rem;
    justify-content: center;
}

.nav-link {
    color: #ffffff;
    text-decoration: none;
}

.nav-link:hover{
    text-decoration: underline;
    text-underline-offset: 4px;
}

.nav-link.selected{
    text-decoration: underline;
    text-underline-offset: 4px;
}

.hamburger {
    --bar-h: 3px;
    --bar-w: 26px;

    background: none;
    border: none;
    cursor: pointer;
    display: none;            /* shown in mobile via media query */
    flex-direction: column;
    gap: 6px;
    padding: 0;
}

.hamburger span {
    width: var(--bar-w);
    height: var(--bar-h);
    background: #fff;
    display: block;
    transition: transform .3s ease, opacity .3s ease;
}

/* ───── open/close animation ───── */
.hamburger.active span:nth-child(1) { transform: translateY(9px) rotate(45deg); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: translateY(-9px) rotate(-45deg); }

/* ───── mobile layout (<768 px) ───── */
@media (max-width: 768px) {
    .hamburger { display: flex;  margin-left:auto;  }


    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        flex-direction: column;
        background: rgba(24, 31, 45, 0.95);
        padding: 1rem 0;
        font-size: 1.5rem;
    }

    .nav-links.open {           /* ② show when toggled */
        display: flex;
        align-items: center;

    }
}