.sticky-nav {
    position: fixed;
    left: 50%;
    bottom: calc(env(safe-area-inset-bottom, 0px) + 12px);
    z-index: 60;
    display: none;
    align-items: center;
    justify-content: space-between;
    gap: 0.9rem;
    width: min(720px, calc(100% - 1.4rem));
    padding: 0.72rem 1rem;
    border: 1px solid rgb(var(--white-rgb) / 0.1);
    border-radius: 999px;
    background:
        radial-gradient(circle at 12% 50%, rgb(var(--pink-rgb) / 0.14), transparent 24%),
        radial-gradient(circle at 88% 50%, rgb(var(--yellow-rgb) / 0.12), transparent 24%),
        linear-gradient(180deg, rgb(var(--white-rgb) / 0.035), rgb(var(--white-rgb) / 0.012)),
        rgb(var(--bg-rgb) / 0.84);
    box-shadow:
        0 18px 50px rgb(var(--black-rgb) / 0.42),
        0 0 0 1px rgb(var(--white-rgb) / 0.025) inset,
        0 0 28px rgb(var(--pink-rgb) / 0.06),
        0 0 18px rgb(var(--yellow-rgb) / 0.05);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    transform: translateX(-50%);
}

.sticky-nav.show {
    display: flex;
}

.sticky-nav a {
    color: inherit;
    text-decoration: none;
    white-space: nowrap;
    touch-action: manipulation;
}

.sticky-nav .nav-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.55rem;
    min-height: 50px;
    padding: 0.72rem 0.95rem;
    border: 0;
    border-radius: 999px;
    background: transparent;
    box-shadow: none;
    color: var(--cream);
    line-height: 1;
    transition:
        transform 0.22s ease,
        color 0.22s ease,
        text-shadow 0.22s ease,
        opacity 0.22s ease;
}

.sticky-nav .nav-btn:hover,
.sticky-nav .nav-btn:focus-visible {
    transform: translateY(-2px);
    color: rgb(var(--white-rgb) / 0.98);
    text-shadow:
        0 0 18px rgb(var(--pink-rgb) / 0.16),
        0 0 12px rgb(var(--yellow-rgb) / 0.12);
}

.sticky-nav .nav-home {
    min-width: 50px;
    justify-content: center;
    padding-inline: 0.35rem;
}

.sticky-nav .nav-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    color: rgb(var(--pink-rgb) / 0.96);
    font-size: 1.45rem;
    line-height: 1;
    transition:
        transform 0.22s ease,
        color 0.22s ease,
        text-shadow 0.22s ease;
}

.sticky-nav .nav-home .nav-icon {
    font-size: 1.55rem;
}

.sticky-nav .nav-label {
    color: var(--text-92);
    font-size: 0.88rem;
    font-weight: 780;
    letter-spacing: 0.01em;
    line-height: 1;
    transition: color 0.22s ease;
}

.sticky-nav .nav-btn:hover .nav-label,
.sticky-nav .nav-btn:focus-visible .nav-label {
    color: rgb(var(--white-rgb) / 0.98);
}

.sticky-nav .nav-btn:hover .nav-icon,
.sticky-nav .nav-btn:focus-visible .nav-icon {
    color: rgb(var(--yellow-rgb) / 0.98);
    text-shadow:
        0 0 14px rgb(var(--yellow-rgb) / 0.16),
        0 0 14px rgb(var(--pink-rgb) / 0.14);
}

.sticky-nav .prev-section:hover .nav-icon,
.sticky-nav .prev-section:focus-visible .nav-icon {
    transform: translateX(-2px);
}

.sticky-nav .next-section:hover .nav-icon,
.sticky-nav .next-section:focus-visible .nav-icon {
    transform: translateX(2px);
}

.sticky-nav .current-section {
    flex: 1;
    min-width: 0;
    padding: 0 0.75rem;
    color: var(--cream);
    font-size: 0.96rem;
    font-weight: 700;
    text-align: center;
    text-overflow: ellipsis;
    white-space: nowrap;
    overflow: hidden;
    text-shadow: 0 1px 0 rgb(var(--white-rgb) / 0.03);
}

.sticky-nav .nav-btn.is-disabled {
    opacity: 0.38;
    pointer-events: none;
    cursor: default;
    text-shadow: none;
    transform: none;
}

.sticky-nav .nav-btn.is-disabled .nav-icon,
.sticky-nav .nav-btn.is-disabled .nav-label {
    color: rgb(var(--white-rgb) / 0.42);
    text-shadow: none;
}

.sticky-nav .nav-btn:focus-visible {
    outline: 2px solid var(--pink);
    outline-offset: 2px;
}

@media (max-width: 720px) {
    .sticky-nav {
        bottom: calc(0.9rem + env(safe-area-inset-bottom));
        z-index: 999;
        gap: 0.45rem;
        width: min(560px, calc(100% - 1.2rem));
        padding: 0.58rem 0.7rem;
    }

    .sticky-nav .nav-btn {
        min-height: 44px;
        padding: 0.45rem 0.35rem;
        gap: 0.3rem;
    }

    .sticky-nav .nav-home {
        min-width: 44px;
        padding-inline: 0.2rem;
    }

    .sticky-nav .nav-icon {
        font-size: 1.38rem;
    }

    .sticky-nav .nav-home .nav-icon {
        font-size: 1.45rem;
    }

    .sticky-nav .current-section {
        padding: 0 0.35rem;
        font-size: 0.86rem;
        font-weight: 650;
    }

    .sticky-nav .nav-label,
    .sticky-nav .nav-text {
        display: none;
    }
}