.chapter_list_item {
  --height_button_add_section: 0;

  padding: 15px;
  border: 1px dashed var(--color_accent_0);
  border-radius: var(--general_border_radius);
  background-color: transparent;

  font-size: var(--fsz_chapter_list);
  color: var(--color_accent_0);

  cursor: pointer;  
  
  transition: color var(--t_fast_transition), background-color var(--t_fast_transition);
}
.chapter_list_item:not(.expanded):hover {
  box-shadow: 0 0 3px var(--color_accent_1);
}
.chapter_list_item.expanded {
  background-color: var(--color_overlay_light);
}  
.chapter_list_item.ready {
  border-style: solid;
  color: inherit;
}

.chapter_list_item .chapter_top {
  display: flex;
  align-items: center;
  gap: var(--general_gap);
}

.chapter_list_item .assignments_progress {
  margin-left: auto;
  margin-right: calc(4 * var(--general_gap));
  display: flex;
  gap: calc(4 * var(--general_gap));
}

/* SECTIONS */
.chapter_list_item ul.section_list {
  --gap: 0;
  --height_basis: 163px;

  display: flex;
  flex-direction: column;
  gap: var(--gap);
  padding: var(--gap) 0;
  transition: padding var(--t_fast_transition), height var(--t_fast_transition);
}


/* ADD SECTION */
.chapter_list_item .add_section {
  height: var(--height_button_add_section);
  overflow: hidden;
}

/* PROGRESS AND ASSIGNMENTS */
.chapter_list_item .progress, .chapter_list_item .assignments {
  --height: calc(1.8 * var(--fsz_chapter_list));
  --dims_assignment: var(--height);
  height: var(--height);
}

/* PROGRESS */
.chapter_list_item .progress {
}
.chapter_list_item .progress > ul {
  height: 100%;
  display: flex;
  gap: 1.5px;
}
.chapter_list_item .progress > ul > li {  
  width: 4.5px;
  border-color: transparent;
  border-width: 1px;
  border-style: solid;

  /* border: .5px solid transparent; */
}
.chapter_list_item .progress > ul > li.status_default {
  background-color: transparent;
  border-color: var(--color_accent_1);
}
.chapter_list_item .progress > ul > li.quiz {
  /* background-color: var(--color_accent_quiz); */
  border-color: var(--color_accent_quiz);
}
.chapter_list_item .progress > ul > li.status_complete {
  background-color: var(--color_accent_completed_general);
  border-color: var(--color_accent_completed_general);
}
.chapter_list_item .progress > ul > li.status_question {
  background-color: var(--color_accent_question);
  border-color: var(--color_accent_question);
}

/* ASSIGNMENTS */
.chapter_list_item .assignments > ul {
  display: flex;
  gap: 4px;
  height: var(--dims_assignment);
}
.chapter_list_item .assignments > ul > li {
  width: var(--dims_assignment);
  border: .5px solid var(--color_accent_1);
  border-radius: 50%;

  background-image: url(../media/assignment.png);
  background-position: center;
  background-size: 55%;
  background-repeat: no-repeat;
}
.chapter_list_item .assignments > ul > li.status_complete {
  background-color: var(--color_accent_completed_general);
}

/* EXPAND COMPRESS */
.chapter_list_item .expand_compress {
  border-radius: 50%;
  background-color: transparent;
  border-color: rgba(0,0,0,.2);
  height: 32px;
  width: 32px;
  padding: 0;

  transition: rotate var(--t_fast_transition);
}
.chapter_list_item .expand_compress:hover {
  border-color: var(--color_accent_2);
}
.chapter_list_item .expand_compress img {
  height: 100%;
}

.chapter_list_item.expanded ul.section_list {
  --gap: 23px;
}  
.chapter_list_item.expanded ul.section_list > .section_item {
  --height: var(--height_basis);
  --padding: 10px;
  --border_width: 1px;
  --section_opacity: 1;
  --height_button_add_section: auto;
}
.chapter_list_item.expanded ul.section_list > .section_item .unit_item {
  --border_width: 1px;
  --internal_margin: 4px;
  --content_padding: calc(var(--size_question) / 5);
  --size_question_unit: var(--size_question); /* resets to value @root */
  --size_icon: calc(.25 * var(--height_basis));
}
.chapter_list_item.expanded {
  --height_button_add_section: auto;
}
.chapter_list_item.expanded .expand_compress {
  rotate: 180deg;
}