A problem occurred evaluating root project 'user-auth-retrofit'

Question

I am using "auth-retrofit" and that problem I face it, and I can't understand where is the problem and why that's my Gradle code and that's the shown error.

"" Build file 'C:\Users\Ammar\AndroidStudioProjects\user-auth-retrofit\build.gradle' line: 7
A problem occurred evaluating root project 'user-auth-retrofit'.Could not find method google() for arguments [] on repository container.""

here's my Build gradle:

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        jcenter()
        maven { url 'https://maven.google.com' }
        google()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.0.0'

    }
}

allprojects {
    repositories {
        jcenter()
        maven { url 'https://maven.google.com' }


    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}