Having hard time importing JZY3D into my project

Question

I'm new to this library, and i just couldn't import it, and i don't know why. I'm using intellji. I have downloaded this demo from git hub: https://github.com/basix86/jzy3d-javafx-demos to try and understand how it works, and here are the problems:

here is the entire code:

    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>com.basix86</groupId>
  <artifactId>chart</artifactId>
  <version>1.0-SNAPSHOT</version>
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <configuration>
          <source>1.8</source>
          <target>1.8</target>
        </configuration>
      </plugin>
    </plugins>
  </build>
  <packaging>jar</packaging>

  <name>chart</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>

  <repositories>
    <repository>
      <id>jzy3d-snapshots</id>
      <name>Jzy3d Snapshots</name>
      <url>http://maven.jzy3d.org/snapshots</url>
    </repository>
  </repositories>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>

    <dependency>
      <groupId>org.jzy3d</groupId>
      <artifactId>jzy3d-api</artifactId>
      <version>1.0.0-SNAPSHOT</version>
    </dependency>

    <dependency>
      <groupId>org.jzy3d</groupId>
      <artifactId>jzy3d-javafx</artifactId>
      <version>1.0.0-SNAPSHOT</version>
    </dependency>

  </dependencies>
</project>