/* Hamburger */
.hamburger {
    display: inline-flex;
    flex-direction: column;
    gap: 4px;
    background: var(--surface-1);
    border: 1px solid var(--border-color);
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    cursor: pointer;
}

/* Hamburger open state */
.hamburger.open span:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
}

.hamburger.open span:nth-child(2) {
    opacity: 0;
    transform: scaleX(0);
}

.hamburger.open span:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
}

.hamburger span {
    transition: transform 0.25s ease, opacity 0.25s ease;
    width: 20px;
    height: 2px;
    background: var(--color-text);
    transform-origin: center;
}

@media (min-width: 951px) {
    .hamburger {
        display: none;
    }
}

/* JS-controlled header mode (collision based) */
.site-header.nav-ready.is-mobile-nav .hamburger {
    display: inline-flex !important;
}

.site-header.nav-ready.is-mobile-nav .desktop-nav {
    display: none !important;
}

.site-header.nav-ready:not(.is-mobile-nav) .hamburger {
    display: none !important;
}

.site-header.nav-ready:not(.is-mobile-nav) .desktop-nav {
    display: flex !important;
}

/* Mobile menu */
.mobile-menu {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none; /* disabled until opened */
    z-index: 200; /* above header */
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.28s ease, visibility 0s linear 0.28s;
}

.mobile-menu.hidden {
    opacity: 0;
    visibility: hidden;
}

/* Backdrop */
.mobile-menu-backdrop {
    position: absolute;
    top: var(--header-height, 73px);
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.4);
    opacity: 0;
    transition: opacity 0.25s ease;
    pointer-events: none;
}

/* Panel that slides down */
.mobile-menu-panel {
    position: absolute;
    top: var(--header-height, 73px); /* adjust to your header height */
    left: 0;
    width: 100%;
    background: var(--color-bg); /* same as header */
    box-shadow: var(--shadow-lg);
    transform: translateY(-20px);
    opacity: 0;
    transition: transform 0.25s ease, opacity 0.25s ease;
    pointer-events: auto;
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
    box-sizing: border-box;
    overflow-x: hidden;
    will-change: transform, opacity;
}

/* When menu is visible */
.mobile-menu:not(.hidden) {
    opacity: 1;
    visibility: visible;
    transition: opacity 0.28s ease, visibility 0s linear 0s;
    pointer-events: none;
}

.mobile-menu:not(.hidden) .mobile-menu-backdrop {
    opacity: 1;
    pointer-events: auto;
}

.mobile-menu:not(.hidden) .mobile-menu-panel {
    transform: translateY(0);
    opacity: 1;
}

.mobile-menu-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.mobile-nav {
    margin-top: 1rem;
    display: grid;
    gap: 0.75rem;
}

.mobile-nav button {
    width: 100%;
    padding: 0.5rem;
    border-radius: var(--radius-md);
    background: var(--surface-1);
    border: 1px solid var(--border-color);
    text-align: center;
    cursor: pointer;
    font-size: 1.1rem; /* larger text */
    line-height: 1;
    transition: background 0.2s ease;
    border: 1px solid var(--border-color);
    font-weight: 500;
    color: var(--color-text);
}

.mobile-nav button:hover {
    background: var(--surface-3);
}

.mobile-nav button.active {
    background: var(--surface-4);
    border-color: rgba(19, 102, 214, 0.5);
}

.mobile-nav button:focus-visible {
    outline: 2px solid rgba(19, 102, 214, 0.9);
    outline-offset: 2px;
}

.mobile-controls {
    margin-top: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

@media (min-width: 951px) {
    .mobile-menu {
        display: none !important;
    }
}