[thiago.eec]

Originally Posted by Brett Merkey

That is precisely why the "clean CSS" Calibre tool will remove all the interesting structural code added in the conversion.

I just did a conversion here, from EPUB to AZW3.

This is the original style sheet:

Spoiler:

.tp {
margin-top: 1em;
text-align: center;
}

h1.otherbooks
{
text-align: center;
font-size: medium;
margin-bottom: 1em;
margin-top: 4em;
}

div.otherbooks
{
margin-top: 4em;
font-size: small;
margin-left: 2em;
margin-right: 2em;
}

div.copyright
{
font-size: small;
text-align: center;
margin-top: 4em;
}

div.dedication
{
font-size: small;
margin-top: 8em;
}

div.epigraph
{
font-size: medium;
margin-left: 12em;
margin-right: 4em;
margin-bottom: 2em;
margin-top: 2em;
}

div.epigraphsource
{
font-size: x-small;
text-align: right;
font-style: italic;
margin-bottom: 12em;
margin-right: 2em;
}

h1.acknowledgments
{
font-size: medium;
margin-top: 4em;
text-align: center;
font-weight: bold;
}

div.acknowledgments
{
font-size: small;
text-align: justify;
margin-left: 2em;
margin-right: 2em;
}

h1.authorsnote
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

div.authorsnote
{
font-size: small;
text-align: justify;
}

h1.listoffigures
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

div.listoffigures
{
font-size: small;
text-align: left;
}

h1.chronology
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.geneology
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.foreword
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.preface
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.introduction
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.prologue
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.part
{
line-height: 2em;
margin-top: 4em;
margin-bottom: 1em;
font-size: large;
text-align: center;
font-weight: bold;
}

h1.chapter
{
font-size: 110%;
text-align: center;
font-weight: normal;
line-height: 1.5em;
margin-top: 4em;
margin-bottom: 6em;
}

h1.subchapter
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.epilogue
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.coda
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.conclusion
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.afterward
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.permission
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.glossary
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

span.glosaryterm
{
font-size: small;
text-align: left;
margin-right: 1em;
}

span.glosarydef
{
font-size: small;
text-align: left;
margin-right: 1em;
}

h1.appendix
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.resource
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.notes
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

div.note
{
font-size: x-small;
text-align: justify;
margin-left: 1em;
}

h1.source
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.bibliography
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

div.bibliography
{
font-size: x-small;
text-align: justify;
margin-left: 2em;
font-weight: bold;
}

h1.suggestedreading
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h1.abouttheauthor
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

p.smallheight
{
margin-top: 1em;
margin-bottom: 1em;
}

p.mediumheight
{
margin-top: 2em;
margin-bottom: 2em;
}

p.attribution
{
text-align: center;
}


p.largeheight
{
margin-top: 3em;
margin-bottom: 3em;
}

div.list
{
font-size: small;
margin-left: 1em;
}


h1.box
{
font-size: medium;
font-style: italic;
text-align: center;
}

div.box
{
font-size: small;
margin-left: 1em;
}

p.caption
{
font-size: x-small;
font-style: italic;
text-align: center;
margin-bottom: 1em;
}


/* ===================== Added Styles ===================== */

p.indent
{
text-indent: 1.00em;
text-align: justify;
}

p.right
{
text-align: right;
}

p.center
{
margin-top: 1em;
text-align: center;
margin-bottom: 1em;
}

a.hlink
{
text-decoration: none;
}

p.figure
{
margin-top: 2em;
text-align: center;
margin-bottom: 2em;
}

h1.subtitle
{
font-size: x-large;
text-align: center;
font-weight: bold;
margin-bottom: 4em;
}


h1.contents
{
font-size: medium;
text-align: center;
font-style: italic;
font-weight: bold;
}

h2.title
{
font-size: medium;
text-align: center;
}

p.smallheight
{
margin-top: 1em;
}

p.mediumheight
{
margin-top: 2em;
}

p
{
margin-top: .3em;
margin-bottom: .3em;
}

div.cover
{
text-align: center;
height: 100%;
}

div.titlepage
{
text-align: center;
margin-top: 1.2em;
margin-left: -.4em;
}

a.pubhlink
{
text-decoration: none;
color: green;
}

p.extract
{
text-align: justify;
margin-top: 2em;
text-indent: 0;
}

p.extract1
{
text-align: justify;
margin-top: 2em;
text-indent: 0;
text-indent: 1.00em;
}

div.textbox
{
margin-top: 2em;
margin-bottom: 2em;
border-bottom: 2px solid;
border-top: 2px solid;
line-height: 1.7em;
text-align: center;
}

h1.caption
{
font-size: medium;
margin-bottom: 1em;
}

p.box
{
border-bottom: 1px double;
border-left: 1px double;
border-top: 1px double;
border-right: 1px double;
text-align: justify;
}

div.abstract
{
font-size: small;
text-align: justify;
margin-left: 2em;
margin-right: 2em;
}

div.appendix
{
font-size: small;
text-align: justify;
}

p.reference
{
text-align: justify;
text-indent: -1.00em;
margin-left: 1em;
}

div.biboliography
{
font-size: medium;
text-align: justify;
}

div.preface
{
font-size: small;
text-align: justify;
margin-left: 2em;
margin-right: 2em;
}

p.cop
{
margin-bottom: 1em;
}

p.nonindent
{
text-align: justify;
text-indent: 0;
}

span.small
{
font-size: x-small;
}

div.toc
{
font-size: medium;
text-align: center;
}

p.stanga
{
text-align: justify;
margin-top: 1em;
margin-bottom: 1em;
margin-left: 2em;
}

body
{
font-size: medium;
line-height: 1.2em;
margin-top: 1em;
margin-left: 1em;
margin-right: 2em;
font-family: Charis, "Times New Roman", Verdana, Arial;
}

@font-face
{
font-family: "Charis";
font-style: normal;
font-weight: normal;
src:url(fonts/CharisSILR.ttf);
}

@font-face
{
font-family: "Charis";
font-style: normal;
font-weight: bold;
src:url(fonts/CharisSILB.ttf);
}

@font-face
{
font-family: "Charis";
font-style: italic;
font-weight: normal;
src:url(fonts/CharisSILI.ttf);
}

@font-face
{
font-family: "Charis";
font-style: italic;
font-weight: bold;
src:url(fonts/CharisSILBI.ttf);
}

h3.title
{
font-size: medium;
text-align: center;
margin-bottom: 3em;
}

span.dropcaps
{
float: left;
font-size: 50px;
line-height: 50px;
padding-top: 1px;
margin-top: -.09em;
margin-right: .09em;
}

span.dropcaps3lines
{
float: left;
font-size: 80px;
line-height: 70px;
padding-top: 1px;
margin-top: -.09em;
margin-right: .09em;
}

sup.small
{
font-size: small;
line-height: 0.0em;
}

div.footnote
{
font-size: small;
border-style: solid;
border-width: 1px 0 0 0;
margin-top: 2em;
}

p.footnote
{
text-align: justify;
margin-left: 2em;
}

p.question
{
text-align: justify;
margin-top: 1em;
}

div.small-page
{
margin-top: 2em;
font-size: medium;
margin-left: 12em;
margin-right: 6em;
}

h1.toc
{
text-align: center;
font-size: 110%;
margin-top: 3em;
margin-bottom: 2em;
font-weight: normal;
}

ol.upperalpha
{
text-align: justify;
list-style-type: upper-alpha;
}

ol.upperroman
{
text-align: justify;
list-style-type: upper-roman;
}

ol.lowerroman
{
text-align: justify;
list-style-type: lower-roman;
}

ol.loweralpha
{
text-align: justify;
list-style-type: lower-alpha;
}


ol.arabic
{
text-align: justify;
}
ul.bullet
{
list-style-type: disc;
}

ul.none
{
text-align: justify;
list-style-type: none;
}

p.hanging
{
text-indent: -1em;
font-size: medium;
margin-left: 2.5em;
margin-top: 0.5em;
}

h1.section
{
text-align: left;
font-size: medium;
margin-bottom: 1em;
margin-top: 4em;
}

h2.section
{
text-align: center;
font-size: medium;
margin-bottom: 1em;
margin-top: 4em;
}

h3.section
{
text-align: left;
font-size: medium;
margin-bottom: 1em;
margin-top: 4em;
}

h4.section
{
text-align: left;
font-size: medium;
margin-bottom: 1em;
margin-top: 4em;
}

h5.section
{
text-align: left;
font-size: medium;
margin-bottom: 1em;
margin-top: 4em;
}

span.underline
{
text-decoration: underline;
}

span.big
{
font-size: large;
}

p.crt
{
margin-top: 1em;
text-align: center;
margin-bottom: 1em;
}

span.overline
{
text-decoration: overline;
}

p.textbox
{
text-align: justify;
margin-left: 1em;
margin-right: 1em;

}

p.textbox1
{
text-indent: 1.00em;
text-align: justify;
margin-left: 1em;
margin-right: 1em;
}

div.chapter
{
margin-top: 2em;
margin-left: 0.5em;
margin-right: 0.5em;
}

span.strike
{
text-decoration: line-through;
}

img
{
max-height: 100%;
max-width: 100%;
}


sup
{
vertical-align: 4px;
}

sup.frac, sub.frac
{
font-size: 0.7em;
}

p.pagebreak
{
page-break-before: always;
}

p.textboxextract
{
margin-top: 2em;
text-align: justify;
margin-left: 1em;
margin-right: 1em;
}

/* =============== New Style added =============== */

/* == For TOC == */

div.toc_fm
{
margin-top:1em;
margin-bottom:1em;
margin-left:1.5em;
font-size:.9em;
line-height:1em;
}

div.toc_bm
{
margin-top:1em;
margin-bottom:1em;
margin-left:1.5em;
font-size:.9em;
line-height:1em;
}

div.toc_chap
{
margin-left:1.5em;
font-size:1em;
line-height:1.4em;
}

div.toc_sub
{
margin-left:2em;
font-size:smaller;
line-height:1.4em;
}

div.toc_part
{
margin-left:1.5em;
line-height:1.5em;
font-size:1.2em;
}

.toc_part .toc_chap
{
font-size:medium;
margin-left:1.5em;
}

.toc_part .toc_chap .toc_sub
{
font-size:smaller;
margin-left:1.5em;
}


/* == For Block Quotes == */

div.block
{
margin-left: 0em;
margin-right: 0em;
text-align:justify;
margin-top: 1em;
margin-bottom: 1em;
font-size: small;
}

p.bl_nonindent
{
margin-left:2.5em;
margin-right:2.5em;
text-align:justify;
}

p.bl_indent
{
text-indent:1em;
margin-left:2.5em;
margin-right:2.5em;
text-align:justify;
}

p.bl_extract
{
margin-left:2.5em;
margin-right:2.5em;
text-align:justify;
margin-top: 2em;
}

p.bl_center
{
margin-left:2.5em;
margin-right:2.5em;
text-align: center;
}

p.bl_right
{
text-align: right;
margin-left:2.5em;
margin-right:2.5em;
}

p.bl_hanging
{
text-indent: -1em;
font-size: medium;
margin-left: 2.5em;
margin-top: 0.5em;
}


/* For Hanging Paragraphs */

div.hanging
{
margin-left: 1.0em;
}

/* For Dialogue Text */

div.dialogue
{
margin-left: 4.2em;
margin-bottom: 2em;
margin-top: 1.5em;
font-size: small;
}

p.d_hanging
{
text-indent: -4.2em;
font-size: small;
margin-top: 0.5em;
}

/* For bullet list */

ul.bullet
{
list-style-type: disc;
margin-top: 1em;
margin-bottom: 1em;
}
div.bullet
{
margin-left: .8em;
margin-top: 0;
margin-bottom: 0;
text-align: justify;
}

/* For Fractions */
.frac_num
{font-size:x-small; vertical-align:text-top;}
.frac_den
{font-size:x-small; vertical-align:text-bottom;}

div.floatleft
{
float: left;
}

div.floatright
{
float: right;
}

h1.chapter0
{
font-size: 110%;
text-align: center;
font-weight: normal;
line-height: 2em;
margin-top: 4em;
margin-bottom: 3em;
}

p.center0
{
margin-top: 1.5em;
text-align: center;
margin-bottom: 1.5em;
}

h1.chapter1
{
font-size: 100%;
text-align: center;
font-weight: normal;
line-height: 2em;
margin-top: 4em;
margin-bottom: 2em;
}

Now, this is the new style sheet after the conversion:

Spoiler:

.calibre {
display: block;
font-family: Charis, "Times New Roman", Verdana, Arial;
font-size: 1rem;
line-height: 1.2em;
padding-left: 0;
padding-right: 0;
margin: 0 5pt
}
.calibre1 {
font-style: italic
}
.calibre2 {
background-color: #FFF;
display: block;
font-family: Charis, "Times New Roman", Verdana, Arial;
font-size: 1rem;
line-height: 1.2em;
padding-left: 0;
padding-right: 0;
text-align: center;
margin: 0 5pt
}
.calibre3 {
height: auto;
max-height: 100%;
max-width: 100%;
width: auto
}
.calibre4 {
display: block
}
.calibre5 {
line-height: 1.2
}
.calibre6 {
font-style: italic;
line-height: 1.2
}
.calibre7 {
display: block;
line-height: 1.2
}
.center {
display: block;
text-align: center;
margin: 1em 0
}
.center1 {
display: block;
text-align: center;
margin: 1.5em 0
}
.chapter {
display: block;
font-size: 110%;
font-weight: normal;
line-height: 1.5em;
text-align: center;
margin: 4em 0 6em
}
.chapter1 {
display: block;
font-size: 110%;
font-weight: normal;
line-height: 2em;
text-align: center;
margin: 4em 0 3em
}
.chapter2 {
display: block;
font-size: 100%;
font-weight: normal;
line-height: 2em;
text-align: center;
margin: 4em 0 2em
}
.copyright {
display: block;
font-size: 0.8rem;
margin-top: 4em;
text-align: center
}
.dedication {
display: block;
font-size: 0.8rem;
margin-top: 8em
}
.extract {
display: block;
text-align: justify;
text-indent: 0;
margin: 2em 0 0.3em
}
.footnote {
border-bottom-style: solid;
border-bottom-width: 0;
border-left-style: solid;
border-left-width: 0;
border-right-style: solid;
border-right-width: 0;
border-top-style: solid;
border-top-width: 1px;
display: block;
font-size: 0.8rem;
margin-top: 2em
}
.footnote1 {
display: block;
text-align: justify;
margin: 0.3em 0 0.3em 2em
}
.frac {
font-size: 0.7em;
line-height: normal;
vertical-align: 4px
}
.hlink {
line-height: 1.2;
text-decoration: none
}
.hlink1 {
text-decoration: none
}
.indent {
display: block;
text-align: justify;
text-indent: 1em;
margin: 0.3em 0
}
.nonindent {
display: block;
line-height: 1.2;
text-align: justify;
text-indent: 0;
margin: 0.3em 0
}
.nonindent1 {
display: block;
text-align: justify;
text-indent: 0;
margin: 0.3em 0
}
.pubhlink {
color: green;
text-decoration: none
}
.small {
font-size: 0.6rem
}
.titlepage {
display: block;
margin-left: -0.4em;
margin-top: 1.2em;
text-align: center
}
.toc {
display: block;
font-size: 110%;
font-weight: normal;
line-height: 1.2;
text-align: center;
margin: 3em 0 2em
}
.toc_chap {
display: block;
font-size: 1em;
line-height: 1.4em;
margin-left: 1.5em
}
.toc_fm {
display: block;
font-size: 0.9em;
line-height: 1.2;
margin-bottom: 1em;
margin-left: 1.5em;
margin-top: 1em
}

The resulting css has a lot of classes called 'calibreXX', and some of the original names are lost. The XHTML files are now referring to this new names. So, if you just paste the old style sheet, and clean the unused rules/classes, all the rules mismatching the text will be deleted, and so will be the classes unused on the XHTML files. Information/formatting will be lost.