After update, blog post titles will not convert to black color

Please help! After an update (Astra or Starter template – I’m not sure), my post titles reverted to white. H1 is supposed to be white, but when I designed the site, I changed the blog post titles to black. Now they will not show up because it’s a white title against a white background. On the blog page the titles show up black, but disappears into white on the individual blog posts. I tried to fix it with the following additional CSS, but it won’t work:

wp-block editor-post-title_input {color: black !important;
}
textarea#post-title-0.editor-post-title_input {color: black !important;
}
h1.entry-title {color: black text-decoration: none !important;
}
h1.itemprop=headline {color: black text-decoration: none !important;
}

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