Add these codes to the Custom CSS box and Save

Cart Page

/* cart Page */
body#cart {
  /* header color */
header#header {
    background-color: #f1f2f3 !important;
}
/* navigation items */
header#header div.header-nav-item>a {
    color: #f1f !important;
}
/* Login text */
header#header [class*="auth"] {
    color: #f1f !important;
}
/* Social Icons */
header#header [class*="social"] svg {
    fill: #f1f;
}
/* Cart icon */
header#header [class*="cart"] svg {
    fill: #f1f;
    stroke: #f1f !important;
}
/* Cart quantity */
header#header span.sqs-cart-quantity {
    color: #f1f;
}
/* Buttons */
header#header a.btn {
    background-color: black !important;
    color: white !important;
}
/* Burger Icon */
header#header .burger-inner>div {
    background-color: #f1f !important;
}
}
/* Burger X Close icon */
body#cart {
  &.header--menu-open header#header .burger-inner>div {
    background-color: #f1f !important;
}
}

Homepage Only

/* Homepage Only */
body.homepage {
  /* header color */
header#header {
    background-color: #f1f2f3 !important;
}
/* navigation items */
header#header div.header-nav-item>a {
    color: #f1f !important;
}
/* Login text */
header#header [class*="auth"] {
    color: #f1f !important;
}
/* Social Icons */
header#header [class*="social"] svg {
    fill: #f1f;
}
/* Cart icon */
header#header [class*="cart"] svg {
    fill: #f1f;
    stroke: #f1f !important;
}
/* Cart quantity */
header#header span.sqs-cart-quantity {
    color: #f1f;
}
/* Buttons */
header#header a.btn {
    background-color: black !important;
    color: white !important;
}
/* Burger Icon */
header#header .burger-inner>div {
    background-color: #f1f !important;
}
}
/* Burger X Close icon */
body.homepage.header--menu-open header#header .burger-inner>div {
    background-color: #f1f !important;
}

Other Pages (exclude homepage)

/* Other Pages */
body:not(.homepage) {
  /* header color */
header#header {
    background-color: #f1f2f3 !important;
}
/* navigation items */
header#header div.header-nav-item>a {
    color: #f1f !important;
}
/* Login text */
header#header [class*="auth"] {
    color: #f1f !important;
}
/* Social Icons */
header#header [class*="social"] svg {
    fill: #f1f;
}
/* Cart icon */
header#header [class*="cart"] svg {
    fill: #f1f;
    stroke: #f1f !important;
}
/* Cart quantity */
header#header span.sqs-cart-quantity {
    color: #f1f;
}
/* Buttons */
header#header a.btn {
    background-color: black !important;
    color: white !important;
}
/* Burger Icon */
header#header .burger-inner>div {
    background-color: #f1f !important;
}
}
/* Burger X Close icon */
body.header--menu-open:not(.homepage) header#header .burger-inner>div {
    background-color: #f1f !important;
}

One Page

Add this code to Page Header Code Injection and Save

<!-- One Page -->
<style>
/* header color */
header#header {
    background-color: #f1f2f3 !important;
}
/* navigation items */
header#header div.header-nav-item>a {
    color: #f1f !important;
}
/* Login text */
header#header [class*="auth"] {
    color: #f1f !important;
}
/* Social Icons */
header#header [class*="social"] svg {
    fill: #f1f;
}
/* Cart icon */
header#header [class*="cart"] svg {
    fill: #f1f;
    stroke: #f1f !important;
}
/* Cart quantity */
header#header span.sqs-cart-quantity {
    color: #f1f;
}
/* Buttons */
header#header a.btn {
    background-color: black !important;
    color: white !important;
}
/* Burger Icon */
header#header .burger-inner>div {
    background-color: #f1f !important;
}
/* Burger X Close icon */
body.header--menu-open header#header .burger-inner>div {
    background-color: #f1f !important;
}
</style>