Так?
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<h1>ALICE'S ADVENTURES IN WONDERLAND</h1>
<h3>Lewis Carroll</h3>
<h2>THE MILLENNIUM FULCRUM EDITION 3.0</h2>
<h3>CHAPTER I</h3>
<h4>Down the Rabbit-Hole</h4>
<p>Alice was beginning to get very tired of sitting by her sister
on the bank, and of having nothing to do: once or twice she had
peeped into the book her sister was reading, but it had no
pictures or conversations in it, 'and what is the use of a book,'
thought Alice 'without pictures or conversation?'</p>
<p>So she was considering in her own mind (as well as she could,
for the hot day made her feel very sleepy and stupid), whether
the pleasure of making a daisy-chain would be worth the trouble
of getting up and picking the daisies, when suddenly a White
Rabbit with pink eyes ran close by her.</p>
<p>Alice was beginning to get very tired of sitting by her sister
on the bank, and of having nothing to do: once or twice she had
peeped into the book her sister was reading, but it had no
pictures or conversations in it, 'and what is the use of a book,'
thought Alice 'without pictures or conversation?'</p>
<p>So she was considering in her own mind (as well as she could,
for the hot day made her feel very sleepy and stupid), whether
the pleasure of making a daisy-chain would be worth the trouble
of getting up and picking the daisies, when suddenly a White
Rabbit with pink eyes ran close by her.</p>
<p>Alice was beginning to get very tired of sitting by her sister
on the bank, and of having nothing to do: once or twice she had
peeped into the book her sister was reading, but it had no
pictures or conversations in it, 'and what is the use of a book,'
thought Alice 'without pictures or conversation?'</p>
<p>So she was considering in her own mind (as well as she could,
for the hot day made her feel very sleepy and stupid), whether
the pleasure of making a daisy-chain would be worth the trouble
of getting up and picking the daisies, when suddenly a White
Rabbit with pink eyes ran close by her.</p>
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Не работает. Фон растягивается по высоте окна. Ниже текст идёт уже на белом фоне. В IE ваще хрень какая-то... Или я неправильно понял Вас?!
А может быть можно как-нибудь повлиять на CSS или background скриптом, находящемся в body, а не в head? Ведь та часть скрипта, которая отвечает за растяжение картинки при расположении в body работает. Тогда бы проблема была решена!