Exhibit 24

                               POWER OF ATTORNEY

       KNOW ALL MEN BY THESE PRESENTS, that each of the undersigned hereby
constitutes and appoints William J. Fitzgerald, Christopher McCain and Mark
Allen, and each of them, with full power to act without the others, his true and
lawful attorney-in-fact, with full power of substitution, to sign any and all
instruments, certificates and documents that may be necessary, desirable or
appropriate to be executed on behalf of himself as an individual or in his
capacity as a direct or indirect general partner, director, officer or manager
of any partnership, corporation or limited liability company, pursuant to
section 13 or 16 of the Securities Exchange Act of 1934, as amended (the
"Exchange Act"), and any and all regulations promulgated thereunder, and to file
the same, with all exhibits thereto, and any other documents in connection
therewith, with the Securities and Exchange Commission, and with any other
entity when and if such is mandated by the Exchange Act or by the Financial
Industry Regulatory Authority, granting unto said attorney-in-fact full power
and authority to do and perform each and every act and thing necessary,
desirable or appropriate, fully to all intents and purposes as he might or could
do in person, thereby ratifying and confirming all that said attorney-in-fact,
or his substitutes, may lawfully do or cause to be done by virtue hereof. This
Power of Attorney shall remain in full force and effect with respect to each
undersigned person unless and until six months after such person is both no
longer a Managing Director of General Catalyst Partners and no longer serving on
the board of directors of any portfolio company of any General Catalyst Partners
fund.

       IN WITNESS WHEREOF, this Power of Attorney has been signed as of the 7th
day of October, 2014.


                                  /s/ Lawrence S. Bohn
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                                  Lawrence S. Bohn

                                  /s/ Joel E. Cutler
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                                  Joel E. Cutler

                                  /s/ David P. Fialkow
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                                  David P. Fialkow

                                  /s/ William J. Fitzgerald
                                  ----------------------------------------------
                                  William J. Fitzgerald

                                  /s/ Stephen A. Herrod
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                                  Stephen A. Herrod

                                  /s/ David J. Orfao
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                                  David J. Orfao

                                  /s/ Neil F. Sequeira
                                  ----------------------------------------------
                                  Neil F. Sequeira

                                  /s/ Brian J. Shortsleeve
                                  ----------------------------------------------
                                  Brian J. Shortsleeve

                                  /s/ Hemant Taneja
                                  ----------------------------------------------
                                  Hemant Taneja

                                  /s/ Adam A. Valkin
                                  ----------------------------------------------
                                  Adam A. Valkin

                                  DocuSigned by:
                                  /s/ Kenneth I. Chenault
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                                  Kenneth I. Chenault

                                  DocuSigned by:
                                  /s/ Kyle T. Doherty
                                  ----------------------------------------------
                                  Kyle T. Doherty

                                  DocuSigned by:
                                  /s/ Holly Maloney
                                  ----------------------------------------------
                                  Holly Maloney

                                  DocuSigned by:
                                  /s/ Paul L. Sagan
                                  ----------------------------------------------
                                  Paul L. Sagan