jetpack compose - Animation duration

MainActivity.kt

package com.cfsuman.jetpackcompose

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.activity.compose.setContent
import androidx.compose.animation.animateColorAsState
import androidx.compose.animation.core.tween
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material.Button
import androidx.compose.material.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
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 {
            MainContent()
        }
    }


    @Composable
    fun MainContent(){
        val isGreen = remember { mutableStateOf(value = true) }

        val animatedColor = animateColorAsState(
            targetValue = if (isGreen.value) Color(0xFF7BB661)
                            else Color(0xFFCC5500),
            animationSpec = tween(durationMillis = 5000)
        )

        Column(
            modifier = Modifier
                .fillMaxSize()
                .background(Color(0xFFF1DDCF))
                .padding(16.dp),
            verticalArrangement = Arrangement.spacedBy(16.dp)
        ) {
            Button(
                onClick = { isGreen.value = !isGreen.value }
            ) {
                Text(text = "Animate Color Change")
            }

            Box(
                modifier = Modifier
                    .fillMaxWidth()
                    .height(250.dp)
                    .background(animatedColor.value)
                    .clip(RoundedCornerShape(16.dp))
            )
        }
    }


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