Floodfill not properly coloring specified parameters - c++

Question

I'm using floodfill() and it's not coloring the places I want it to, instead it colors the entire window.
I want the Cyan background inside the rectangle and the magenta under the line line(conx(30) - 2, cony(0)+2, conx(100) + 2, cony(30) - 2); but still within the rectangle boundary.
Here's the code, with relevant libraries included:
#include <iostream>
#include <graphics.h>
#include <cmath>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>
using namespace std;
//convert to pixel value (scale of 6)
double conx(double x)
{
return x * (600/100) + 50;
}
double cony(double y)
{
return -y * (600/100) + 650;
}
int main()
{
initwindow(700,700);
rectangle(50, 0, 650, 650);
setfillstyle(SOLID_FILL, CYAN);
floodfill(100, 100, CYAN);
setfillstyle(SOLID_FILL, MAGENTA);
floodfill(620, 620, MAGENTA);
settextstyle(DEFAULT_FONT, HORIZ_DIR, 3);
outtextxy(150, 655, "ELASTIC PARTICLE");
setcolor(15);
setcolor(15);
line(0, 0, 700, 0);
line(50, 0, 50, 650);
line(650, 0, 650, 652);
line(50, 650, 652, 650);
//drawing the line for the wedge/incline
line(conx(30) - 2, cony(0)+2, conx(100) + 2, cony(30) - 2);
//borders
setcolor(15);
line(0, 0, 700, 0);
line(50, 0, 50, 650);
line(650, 0, 650, 652);
line(50, 650, 652, 650);
}
Here's the sample of the output