jetpack compose - Card background color

MainActivity.kt

package com.cfsuman.jetpackcompose

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.activity.compose.setContent
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material.*
import androidx.compose.runtime.*
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Brush
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.dp

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        setContent {
            GetScaffold()
        }
    }


    @Composable
    fun GetScaffold(){
        Scaffold(
            topBar = {TopAppBar(
                title = {Text(
                    "Compose - Card Background Color",
                    color = Color.White)},
                backgroundColor = Color(0xFF58427C)) },
            content = {MainContent()},
            backgroundColor = Color(0xFFEDEAE0)
        )
    }


    @Composable
    fun MainContent(){
        Column(
            modifier = Modifier
                .fillMaxSize()
                .padding(12.dp),
            verticalArrangement = Arrangement.SpaceEvenly,
            horizontalAlignment = Alignment.CenterHorizontally
        ) {
            Card(
                modifier = Modifier
                    .fillMaxWidth()
                    .height(175.dp),
                backgroundColor = Color(0xFFFFBCD9),
                elevation = 4.dp,
                shape = RoundedCornerShape(24.dp),
            ) {
                Box(Modifier.padding(16.dp)) {
                    Text(
                        text = "Card Solid Background",
                        style = MaterialTheme.typography.h6
                    )
                }
            }

            Card(
                modifier = Modifier
                    .fillMaxWidth()
                    .height(175.dp),
                backgroundColor= Color.Transparent,
                elevation = 4.dp,
                shape = RoundedCornerShape(24.dp),
            ) {
                Box(
                    Modifier
                        .background(
                            Brush.radialGradient(
                                listOf(
                                    Color(0XFFFAD6A5),
                                    Color(0XFFFF5470),
                                    Color(0XFF7DF9FF)
                                )
                            )
                        )
                        .padding(12.dp)
                ) {
                    Text(
                        text = "Card Gradient Background",
                        style = MaterialTheme.typography.h6
                    )
                }
            }
        }
    }


    @Preview
    @Composable
    fun ComposablePreview(){
        //GetScaffold()
    }
}