.top-nav {
    display: flex;
    align-items: stretch;
    align-self: stretch;
    gap: 16px;
    min-width: 0;
}

.top-nav__link {
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 44px;
    height: var(--header-height);
    padding: 0 6px;
    color: var(--color-text);
    font-size: 16px;
    font-weight: 500;
    white-space: nowrap;
    transition: color var(--transition-fast);
}

.top-nav__link::after {
    position: absolute;
    right: 0;
    bottom: 13px;
    left: 0;
    height: 2px;
    border-radius: 2px 2px 0 0;
    background: var(--color-primary);
    content: "";
    opacity: 0;
    transform: scaleX(0.45);
    transition: opacity var(--transition-fast), transform var(--transition-fast);
}

.top-nav__link:hover,
.top-nav__link.is-active {
    color: var(--color-primary);
}

.top-nav__link.is-active::after {
    opacity: 1;
    transform: scaleX(1);
}

.header-actions,
.auth-nav {
    display: flex;
    align-items: center;
}

.header-actions {
    display: flex;
    align-items: center;
    min-width: 0;
    flex: 0 1 auto;
    gap: 10px;
}

.header-quick-actions {
    display: flex;
    align-items: center;
    gap: 2px;
}

.header-icon-action {
    display: inline-grid;
    width: 40px;
    height: 42px;
    flex: 0 0 40px;
    place-items: center;
    padding: 0;
    border: 0;
    border-radius: 6px;
    outline: 0;
    background: transparent;
    color: var(--color-icon);
    cursor: pointer;
    transition: color var(--transition-fast), background-color var(--transition-fast);
}

.header-icon-action:hover {
    background: var(--color-surface-hover);
    color: var(--color-primary);
}

.header-icon-action:focus-visible {
    outline: 3px solid rgba(20, 126, 255, 0.35);
    outline-offset: 1px;
}

.header-icon-action .icon {
    width: 20px;
    height: 20px;
    stroke-width: 1.8;
}

.header-icon-action.sidebar-toggle,
.header-icon-action.header-mobile-search {
    display: none;
}

.site-search {
    display: flex;
    align-items: center;
    width: 254px;
    min-width: 140px;
    max-width: 100%;
    height: 42px;
    flex: 0 1 254px;
    border: 1px solid var(--color-border);
    border-radius: 14px;
    background: var(--color-input);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.site-search:focus-within {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(20, 126, 255, 0.12);
}

.site-search input {
    width: 100%;
    min-width: 0;
    height: 100%;
    padding: 0 8px 0 16px;
    border: 0;
    outline: 0;
    background: transparent;
    color: var(--color-text);
    font-size: 13px;
}

.site-search input::placeholder {
    color: var(--color-text-secondary);
    opacity: 1;
}

.site-search input::-webkit-search-cancel-button {
    display: none;
}

.site-search button {
    display: grid;
    width: 43px;
    height: 40px;
    flex: 0 0 43px;
    place-items: center;
    padding: 0;
    border-radius: 12px;
    background: transparent;
    color: var(--color-icon);
}

.site-search button:hover {
    color: var(--color-primary);
}

.site-search button .icon {
    width: 19px;
    height: 19px;
    stroke-width: 2;
}

.auth-nav {
    gap: 24px;
    height: 42px;
}

.auth-nav__login {
    display: inline-flex;
    align-items: center;
    height: 42px;
    padding: 0 2px;
    font-size: 15px;
    font-weight: 500;
    white-space: nowrap;
    transition: color var(--transition-fast);
}

.auth-nav__login:hover {
    color: var(--color-primary);
}

.auth-nav__register {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 42px;
    border-radius: 6px;
    background: linear-gradient(135deg, #2088ff 0%, #0869ec 100%);
    box-shadow: var(--shadow-primary);
    color: var(--color-on-primary);
    font-size: 15px;
    font-weight: 500;
    white-space: nowrap;
    transition: filter var(--transition-fast), box-shadow var(--transition-fast);
}

.auth-nav__register:hover {
    filter: brightness(1.06);
    box-shadow: 0 8px 18px rgba(20, 126, 255, 0.31);
}

.account-menu {
    position: relative;
    width: 36px;
    height: 36px;
    flex: 0 0 36px;
}

.account-menu__trigger {
    display: grid;
    width: 36px;
    height: 36px;
    place-items: center;
    padding: 0;
    border: 0;
    border-radius: 50%;
    background: transparent;
    color: inherit;
    cursor: pointer;
    list-style: none;
    box-shadow: none;
    transition: background-color var(--transition-fast);
}

.account-menu__trigger::-webkit-details-marker {
    display: none;
}

.account-menu__trigger:hover,
.account-menu[open] .account-menu__trigger {
    background: var(--color-surface-hover);
}

.account-menu__trigger:focus-visible {
    outline: 3px solid rgba(20, 126, 255, 0.35);
    outline-offset: 1px;
}

.account-menu__avatar {
    display: grid;
    width: 32px;
    height: 32px;
    place-items: center;
    overflow: hidden;
    border-radius: 50%;
    background: #ffffff;
    box-shadow: inset 0 0 0 1px rgba(18, 30, 52, 0.08);
}

.account-menu__avatar img {
    display: block;
    width: auto;
    height: auto;
    max-width: 100%;
    max-height: 100%;
    border-radius: 50%;
    object-fit: contain;
    object-position: center;
}

.account-menu__panel {
    position: absolute;
    top: calc(100% + 10px);
    right: 0;
    z-index: 160;
    box-sizing: border-box;
    width: 220px;
    min-width: 220px;
    max-width: min(220px, calc(100vw - 24px));
    padding: 8px;
    border: 1px solid var(--color-border-soft);
    border-radius: 14px;
    background: var(--color-surface);
    box-shadow: 0 14px 36px rgba(18, 30, 52, 0.14);
    opacity: 0;
    transform: translate3d(0, -6px, 0) scale(0.98);
    transform-origin: top right;
    pointer-events: none;
    transition:
        opacity 160ms ease,
        transform 160ms ease,
        visibility 160ms ease;
    visibility: hidden;
}

.account-menu[open] .account-menu__panel {
    pointer-events: auto;
    visibility: visible;
}

.account-menu[open].is-open .account-menu__panel {
    opacity: 1;
    transform: translate3d(0, 0, 0) scale(1);
}

.account-menu[open].is-closing .account-menu__panel {
    opacity: 0;
    transform: translate3d(0, -6px, 0) scale(0.98);
    pointer-events: none;
}

:root[data-theme="dark"] .account-menu__panel {
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.34);
}

:root[data-theme="dark"] .account-menu__avatar {
    background: #ffffff;
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.1);
}

.account-menu__identity {
    display: grid;
    gap: 2px;
    min-width: 0;
    padding: 10px 10px 12px;
    margin-bottom: 4px;
    border-bottom: 1px solid var(--color-border-soft);
}

.account-menu__identity strong,
.account-menu__identity small {
    display: block;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.account-menu__identity strong {
    color: var(--color-text);
    font-size: 14px;
    font-weight: 600;
    line-height: 1.3;
}

.account-menu__identity small {
    color: var(--color-text-secondary);
    font-size: 12px;
    line-height: 1.35;
}

.account-menu__item {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    min-width: 0;
    min-height: 40px;
    padding: 0 10px;
    border: 0;
    border-radius: 10px;
    background: transparent;
    color: var(--color-text);
    font-size: 14px;
    font-weight: 500;
    line-height: 1.2;
    text-align: left;
    white-space: nowrap;
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

.account-menu__item > span {
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.account-menu__item:hover {
    background: var(--color-surface-active);
    color: var(--color-primary);
}

.account-menu__item .icon {
    width: 17px;
    height: 17px;
    flex: 0 0 17px;
}

.account-menu__logout {
    display: block;
    width: 100%;
    margin: 0;
}

.account-menu__item--logout {
    color: var(--color-red);
}

.account-menu__item--logout:hover {
    background: var(--color-red-soft);
    color: var(--color-red);
}

.side-nav {
    display: grid;
    gap: 0;
}

.side-nav__link {
    display: flex;
    align-items: center;
    gap: 17px;
    width: 100%;
    height: 46px;
    padding: 0 15px;
    border-radius: 6px;
    color: var(--color-text);
    font-size: 16px;
    font-weight: 500;
    white-space: nowrap;
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

.side-nav__link .icon {
    width: 20px;
    height: 20px;
    color: currentColor;
    stroke-width: 1.9;
}

.side-nav__link:hover {
    background: var(--color-surface-hover);
    color: var(--color-primary);
}

.side-nav__link.is-active {
    background: var(--color-surface-active);
    color: var(--color-primary);
}

.side-nav__link.is-active .icon--filled {
    stroke: none;
}

.sidebar-divider {
    width: calc(100% - 26px);
    height: 1px;
    margin: 10px 13px 18px;
    background: var(--color-border);
}

.sidebar-label {
    margin: 0 12px 8px;
    color: var(--color-text-secondary);
    font-size: 14px;
    font-weight: 500;
    line-height: 20px;
}

.side-nav--forums .side-nav__link {
    gap: 17px;
}

.side-nav--forums {
    gap: 0;
}

.sidebar-label--tags {
    margin-top: 14px;
}

.sidebar-tags {
    display: grid;
    gap: 0;
}

.sidebar-tag {
    display: flex;
    align-items: center;
    gap: 17px;
    width: 100%;
    height: 40px;
    padding: 0 15px;
    border-radius: 6px;
    color: var(--color-text);
    font-size: 14px;
    font-weight: 500;
    line-height: 20px;
    white-space: nowrap;
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

.sidebar-tag__mark {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 20px;
    height: 20px;
    flex: 0 0 20px;
    color: currentColor;
    font-size: 14px;
    font-weight: 600;
    line-height: 20px;
}

.sidebar-tag:hover {
    background: var(--color-surface-active);
    color: var(--color-primary);
}

.button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    width: 132px;
    height: 47px;
    border: 1px solid transparent;
    border-radius: 6px;
    font-size: 16px;
    font-weight: 500;
    line-height: 1;
    white-space: nowrap;
    transition: background-color var(--transition-fast), border-color var(--transition-fast), color var(--transition-fast), filter var(--transition-fast), box-shadow var(--transition-fast);
}

.button .icon {
    width: 20px;
    height: 20px;
    stroke-width: 1.9;
}

.button--primary {
    background: linear-gradient(135deg, #2088ff 0%, #096bf0 100%);
    box-shadow: var(--shadow-primary);
    color: var(--color-on-primary);
}

.button--primary:hover {
    filter: brightness(1.06);
}

.button--secondary {
    border-color: var(--color-border);
    background: transparent;
    color: var(--color-text);
}

.button--secondary:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

@media (min-width: 641px) {
    .header-icon-action.sidebar-toggle,
    .header-icon-action.header-mobile-search {
        display: none !important;
    }
}

@media (max-width: 1120px) {
    .top-nav {
        gap: 12px;
    }
    .site-search {
        width: 205px;
    }

    .header-actions {
        gap: 16px;
    }

    .header-quick-actions {
        gap: 2px;
    }

    .auth-nav {
        gap: 12px;
    }
}

@media (max-width: 900px) {
    .top-nav__link:nth-child(4),
    .top-nav__link:nth-child(5) {
        display: none;
    }

    .site-search {
        width: 190px;
    }
}

@media (max-width: 720px) {
    .top-nav {
        display: none;
    }

    .header-main {
        justify-content: flex-end;
    }
}

@media (max-width: 640px) {
    .header-icon-action.sidebar-toggle {
        position: absolute;
        top: 50%;
        left: 0;
        z-index: 1;
        display: inline-grid;
        transform: translateY(-50%);
    }

    .header-icon-action.sidebar-toggle .sidebar-toggle__icon {
        width: 22px;
        height: 22px;
        stroke-width: 2.4;
    }

    .sidebar-toggle__line {
        transform-box: view-box;
        transform-origin: center;
        vector-effect: non-scaling-stroke;
        transition: transform 240ms cubic-bezier(0.4, 0, 0.2, 1), opacity 160ms ease;
    }

    .sidebar-toggle__line--top {
        transform: translateY(-6.4px);
    }

    .sidebar-toggle__line--bottom {
        transform: translateY(6.4px);
    }

    .sidebar-toggle[aria-expanded="true"] .sidebar-toggle__line--top {
        transform: rotate(45deg) scaleX(0.78);
    }

    .sidebar-toggle[aria-expanded="true"] .sidebar-toggle__line--middle {
        opacity: 0;
        transform: scaleX(0.35);
    }

    .sidebar-toggle[aria-expanded="true"] .sidebar-toggle__line--bottom {
        transform: rotate(-45deg);
    }

    .header-actions {
        width: auto;
        min-width: 0;
        flex: 0 0 auto;
        gap: 1px;
    }

    .site-search {
        display: none;
    }

    .header-icon-action.header-mobile-search {
        display: inline-grid;
    }

    .header-quick-actions {
        flex: 0 0 auto;
        gap: 0;
    }

    .header-icon-action {
        width: 44px;
        height: 44px;
        flex-basis: 44px;
        border-radius: 6px;
    }

    .header-icon-action .icon {
        width: 19px;
        height: 19px;
    }

    .auth-nav__login {
        display: none;
    }

    .auth-nav {
        height: 44px;
        flex: 0 0 auto;
        gap: 0;
        margin-left: 1px;
    }

    .auth-nav__register {
        width: 48px;
        height: 44px;
        border-radius: 6px;
        font-size: 14px;
    }

    .auth-nav--login-only .auth-nav__login {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        width: 48px;
        height: 44px;
        padding: 0;
        border-radius: 6px;
        background: linear-gradient(135deg, #2088ff 0%, #0869ec 100%);
        box-shadow: var(--shadow-primary);
        color: var(--color-on-primary);
        font-size: 14px;
    }

    .account-menu,
    .account-menu__trigger {
        width: 36px;
        height: 36px;
    }

    .account-menu__trigger:hover,
    .account-menu[open] .account-menu__trigger {
        background: transparent;
    }

    .account-menu__panel {
        right: 0;
        width: 220px;
        min-width: 220px;
        max-width: min(220px, calc(100vw - 24px));
    }
}

@media (prefers-reduced-motion: reduce) {
    .account-menu__panel {
        transition: none;
    }
}