:root {
    --nb-nav-bg: #1093E6;
    --nb-nav-border: rgba(255, 255, 255, 0.12);
    --nb-text-main: #ffffff;
}

.nb-topbar {
    height: 68px;
    display: flex;
    align-items: center;
    gap: 18px;
    padding: 0 20px;
    background: var(--nb-nav-bg);
    border-bottom: 1px solid var(--nb-nav-border);
    flex-shrink: 0;
}

.nb-topbar__menu-btn {
    width: 42px;
    height: 42px;
    border: none;
    border-radius: 12px;
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.18), rgba(0, 77, 170, 0.18));
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 4px;
    cursor: pointer;
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.16);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.nb-topbar__menu-btn:hover {
    transform: scale(1.04);
}

.nb-topbar__menu-btn:active {
    transform: scale(0.96);
}

.nb-topbar__menu-btn span {
    display: block;
    width: 16px;
    height: 2px;
    background: #ffffff;
    border-radius: 10px;
}

.nb-topbar__title {
    margin: 0;
    font-size: 20px;
    font-weight: 700;
    color: var(--nb-text-main);
    line-height: 1;
}

@media (max-width: 480px) {
    .nb-topbar {
        padding: 0 16px;
        gap: 14px;
    }

    .nb-topbar__title {
        font-size: 15px;
    }
}

/* topbar size override */
.nb-topbar {
    height: 68px;
    gap: 16px;
    padding: 0 18px;
}

.nb-topbar__menu-btn {
    width: 38px;
    height: 38px;
}

.nb-topbar__title {
    font-size: 18px;
}

/* tablet */
@media (max-width: 768px) {
    .nb-topbar {
        height: 60px;
        gap: 14px;
        padding: 0 16px;
    }

    .nb-topbar__menu-btn {
        width: 34px;
        height: 34px;
    }

    .nb-topbar__title {
        font-size: 16px;
    }
}

/* phone */
@media (max-width: 480px) {
    .nb-topbar {
        height: 54px;
        gap: 10px;
        padding: 0 12px;
    }

    .nb-topbar__menu-btn {
        width: 30px;
        height: 30px;
    }

    .nb-topbar__title {
        font-size: 14px;
    }
}