.top-nav {
    height: var(--topnav-height);
    background-color: var(--bg-surface);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 28px;
    position: sticky;
    top: 0;
    z-index: 50;
    box-shadow: var(--shadow-sm);
}

.sidebar-toggle {
    background: none;
    border: none;
    font-size: 20px;
    cursor: pointer;
    padding: 8px;
    border-radius: var(--border-radius-sm);
    color: var(--text-secondary);
    margin-right: 16px;
    transition: all var(--transition-fast);
}

.sidebar-toggle:hover {
    background-color: var(--hover-bg);
    color: var(--text-primary);
}

.search-box {
    flex: 1;
    max-width: 420px;
    display: flex;
    align-items: center;
    background-color: var(--hover-bg);
    border-radius: var(--border-radius);
    padding: 10px 16px;
    margin: 0 28px;
    border: 1px solid transparent;
    transition: all var(--transition-fast);
}

.search-box:focus-within {
    background-color: var(--bg-surface);
    border-color: var(--border-color);
    box-shadow: var(--shadow-sm);
}

.search-icon {
    font-size: 14px;
    color: var(--text-muted);
    margin-right: 10px;
    flex-shrink: 0;
}

.search-input {
    flex: 1;
    border: none;
    background: transparent;
    font-size: 14px;
    color: var(--text-primary);
    outline: none;
}

.search-input::placeholder {
    color: var(--text-muted);
}

.top-nav-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-btn {
    background: none;
    border: none;
    font-size: 18px;
    cursor: pointer;
    padding: 10px 12px;
    border-radius: var(--border-radius-sm);
    color: var(--text-secondary);
    position: relative;
    transition: all var(--transition-fast);
}

.nav-btn:hover {
    background-color: var(--hover-bg);
    color: var(--text-primary);
}

.nav-btn .badge {
    position: absolute;
    top: 6px;
    right: 6px;
    min-width: 18px;
    height: 18px;
    font-size: 10px;
    padding: 0 6px;
}

.user-menu {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 14px;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all var(--transition-fast);
    margin-left: 4px;
}

.user-menu:hover {
    background-color: var(--hover-bg);
}

.user-avatar {
    width: 34px;
    height: 34px;
    border-radius: 50%;
    background-color: var(--primary-color);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    box-shadow: 0 2px 4px rgba(0, 163, 196, 0.2);
}

.avatar-text {
    color: white;
    font-size: 14px;
    font-weight: 600;
}

.user-name {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
    white-space: nowrap;
}

.user-arrow {
    font-size: 12px;
    color: var(--text-muted);
    transition: transform var(--transition-fast);
}

.user-menu:hover .user-arrow {
    transform: rotate(180deg);
}

@media (max-width: 768px) {
    .search-box {
        display: none;
    }
    .top-nav {
        padding: 0 16px;
    }
    .user-name {
        display: none;
    }
    .nav-btn {
        padding: 8px 10px;
        font-size: 16px;
    }
}