.study-block {
  position: relative;
  padding: 1rem 1.1rem;
  border-left: 4px solid var(--accent);
  background: var(--surface);
}

.study-block > h3:first-of-type {
  padding-right: 6rem;
}

.study-block > :last-child {
  margin-bottom: 0;
}

.study-block__flag {
  margin: 0 0 0.45rem;
  color: var(--muted);
  font-size: 0.74rem;
  font-weight: 700;
  text-transform: lowercase;
}

.study-block--question {
  position: relative;
  padding-bottom: 2.25rem;
}

.definition,
.rule-statement,
.takeaway {
  font-weight: 650;
}

.term-translation {
  margin-left: 0.45rem;
  color: var(--muted);
  font-size: 0.92rem;
  font-weight: 650;
}

.term-marker {
  margin-left: 0.18rem;
  font-size: 0.72em;
}

.term-marker a {
  color: var(--accent);
  text-decoration: none;
}

.rule-statement,
.takeaway {
  padding: 0.75rem 0.9rem;
  background: var(--attention-soft);
}

.comparison,
.symbols {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
  margin: 0 0 1rem;
}

.comparison div,
.symbols div {
  padding: 0.8rem;
  border: 1px solid var(--border);
  background: var(--surface-muted);
}

dt {
  font-weight: 750;
}

dd {
  margin: 0.25rem 0 0;
}

.steps {
  margin-bottom: 0;
  padding-left: 1.5rem;
}

.steps li + li {
  margin-top: 0.45rem;
}

.annotation-mark {
  position: relative;
  border-bottom: 1px dotted var(--accent);
  color: inherit;
  cursor: help;
  text-decoration: none;
}

.annotation-mark:focus {
  outline: 2px solid var(--accent-soft);
  outline-offset: 2px;
}

.annotation-popover {
  position: absolute;
  z-index: 10;
  display: none;
  width: min(28rem, 80vw);
  padding: 0.75rem 0.85rem;
  border: 1px solid var(--border);
  background: var(--surface);
  box-shadow: 0 0.45rem 1.1rem rgb(0 0 0 / 0.14);
  color: var(--text);
  font-size: 0.82rem;
  font-weight: 500;
  line-height: 1.45;
}

.annotation-popover.is-visible {
  display: grid;
  gap: 0.35rem;
}

.annotation-popover__label,
.annotation-popover__boundary {
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 750;
  text-transform: lowercase;
}

.annotation-popover__title {
  font-weight: 750;
}

.annotation-preview > :first-child {
  margin-top: 0;
}

.annotation-preview > :last-child {
  margin-bottom: 0;
}

.annotation-preview h3 {
  margin-bottom: 0.35rem;
  font-size: 0.95rem;
}

.annotation-preview p,
.annotation-preview ul,
.annotation-preview ol,
.annotation-preview dl {
  margin-block: 0.35rem;
}

.annotation-preview ul,
.annotation-preview ol {
  padding-left: 1.1rem;
}

.annotation-preview__goto {
  display: inline-block;
  margin-top: 0.35rem;
  font-weight: 750;
}

.table-wrap {
  max-width: 100%;
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface);
}

caption {
  padding-bottom: 0.55rem;
  color: var(--muted);
  text-align: left;
}

th,
td {
  padding: 0.7rem 0.8rem;
  border: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}

thead th {
  background: var(--surface-muted);
}

figure {
  margin: 0 0 1rem;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
  border: 1px solid var(--border);
}

figcaption {
  margin-top: 0.5rem;
  color: var(--muted);
}

.formula {
  overflow-x: auto;
  padding: 0.85rem;
  background: var(--surface-muted);
  text-align: center;
}

.formula + .symbols {
  margin-top: 1rem;
}

pre {
  overflow-x: auto;
  padding: 1rem;
  background: var(--code);
  color: var(--code-text);
}

code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}

.question-prompt {
  font-size: 1.08rem;
}

.display-latex {
  overflow-x: auto;
  margin: 0.65rem 0 1rem;
  padding: 0.75rem;
  background: var(--surface-muted);
  text-align: center;
}

.display-latex__item + .display-latex__item {
  margin-top: 0.5rem;
}

.study-subsections {
  display: grid;
  gap: 0.85rem;
  margin-top: 1rem;
}

.study-subsection {
  padding-top: 0.85rem;
  border-top: 1px solid var(--border);
}

.study-subsection > :first-child {
  margin-top: 0;
}

.study-subsection > :last-child {
  margin-bottom: 0;
}

.question-set {
  display: grid;
  gap: 0.55rem;
}

.question-set__actions {
  display: flex;
  justify-content: flex-end;
}

.question-action {
  padding: 0.55rem 0.85rem;
  border: 1px solid #c95f5f;
  background: #fff5f5;
  color: #9f2f2f;
  cursor: pointer;
  font: inherit;
  white-space: nowrap;
}

.question-action--toggle {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent);
}

.question-action--check {
  border-color: var(--accent);
  background: var(--surface);
  color: var(--accent);
}

.question-action--complete {
  border-color: var(--accent);
  background: var(--surface);
  color: var(--accent);
}

.question-action:hover,
.question-action:focus {
  border-color: #9f2f2f;
  background: #fde7e7;
  color: #7d2020;
}

.question-action--toggle:hover,
.question-action--toggle:focus,
.question-action--check:hover,
.question-action--check:focus,
.question-action--complete:hover,
.question-action--complete:focus {
  border-color: var(--accent);
  background: #cce5d8;
  color: var(--accent);
}

.question-action:disabled {
  cursor: progress;
  opacity: 0.65;
}

.question-group.topic--collapsed {
  padding-bottom: 0.45rem;
}

.question-group.topic--collapsed + .question-group.topic--collapsed {
  padding-top: 0;
  border-top: 0;
}

.question-group[data-question-group-complete="true"] {
  background: #f4fbf7;
}

.question-group[data-question-group-complete="true"] > .topic__summary {
  border-left-color: var(--accent);
  background: #dcefe6;
}

.question-group[data-question-group-complete="true"] .question-action--complete {
  border-color: var(--accent);
  background: var(--accent);
  color: #fff;
}

.question-group .topic__summary {
  display: grid;
  grid-template-columns: minmax(12rem, 1fr) auto auto;
  align-items: center;
  gap: 0.8rem 1rem;
  min-height: 4.2rem;
}

.question-group__title {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.question-group__meta {
  display: grid;
  justify-items: stretch;
  gap: 0.35rem;
}

.question-group__actions {
  display: grid;
  grid-auto-columns: minmax(8.5rem, auto);
  grid-auto-flow: column;
  grid-template-rows: repeat(2, auto);
  align-content: center;
  gap: 0.5rem;
}

.question-group__actions .question-action {
  min-height: 1.9rem;
  padding: 0.35rem 0.75rem;
}

.question-answer {
  margin-top: 1rem;
  padding-top: 0.8rem;
  border-top: 1px solid var(--border);
}

.question-answer summary {
  color: var(--accent);
  cursor: pointer;
  font-weight: 750;
}

.question-answer ul {
  margin-bottom: 0;
}

.question-links {
  margin: 0.85rem 0;
}

.answer-draft {
  display: grid;
  gap: 0.35rem;
  margin-top: 1rem;
}

.answer-draft__header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.75rem;
}

.answer-draft__header > span {
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 750;
}

.answer-draft__status {
  position: relative;
  opacity: 0.55;
}

.answer-draft__status[data-answer-draft-state="saved"] {
  cursor: help;
  text-decoration: underline dotted;
  text-underline-offset: 0.18em;
}

.answer-draft__status[data-answer-draft-state="saved"]::after {
  position: absolute;
  right: 0;
  bottom: calc(100% + 0.35rem);
  z-index: 5;
  display: none;
  width: max-content;
  max-width: min(18rem, 70vw);
  padding: 0.45rem 0.55rem;
  border: 1px solid var(--border-strong);
  background: var(--surface);
  box-shadow: var(--shadow);
  color: var(--text);
  content: "Saved locally in this browser so you can continue later; it is not submitted anywhere.";
  font-size: 0.72rem;
  font-weight: 600;
  line-height: 1.35;
  white-space: normal;
}

.answer-draft__status[data-answer-draft-state="saved"]:hover::after,
.answer-draft__status[data-answer-draft-state="saved"]:focus::after {
  display: block;
}

.answer-draft textarea {
  width: 100%;
  min-height: 7rem;
  overflow: hidden;
  resize: vertical;
  padding: 0.7rem;
  border: 1px solid var(--border);
  background: var(--surface-muted);
  color: var(--text);
  font: inherit;
}

.answer-draft textarea:focus {
  border-color: var(--accent);
  outline: 2px solid var(--accent-soft);
}

.answer-check {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin-top: 0.8rem;
}

.answer-check__status {
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 750;
}

.answer-check__correction {
  flex: 1 0 100%;
  margin: 0.15rem 0 0;
  padding: 0.55rem 0.65rem;
  border-left: 3px solid #b63b3b;
  background: #fff7f7;
  color: #7d2020;
  font-size: 0.86rem;
}

.study-block--question[data-answer-check-state="correct"] {
  border-left-color: var(--accent);
  background: #f4fbf7;
}

.study-block--question[data-answer-check-state="incorrect"] {
  border-left-color: #b63b3b;
  background: #fff7f7;
}

.study-block--question[data-answer-check-state="error"] {
  border-left-color: var(--attention);
  background: #fffaf0;
}

.study-block--question[data-answer-check-state="stale"] {
  border-left-color: var(--border-strong);
  background: var(--surface-muted);
}

.study-block--question[data-answer-check-state="correct"] .answer-check__status {
  color: var(--accent);
}

.study-block--question[data-answer-check-state="incorrect"] .answer-check__status,
.study-block--question[data-answer-check-state="error"] .answer-check__status {
  color: #9f2f2f;
}

.study-block--question[data-answer-check-state="stale"] .answer-check__status,
.study-block--question[data-answer-check-state="stale"] .answer-check__correction {
  color: var(--muted);
}

.q-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0 0 0.8rem;
}

.q-tags--summary {
  margin: 0;
  justify-content: stretch;
}

.question-action,
.q-tag,
.question-group .topic__count {
  font-size: 0.78rem;
  font-weight: 750;
  line-height: 1.2;
  text-align: center;
}

.q-tag {
  display: inline-block;
  min-width: 8.5rem;
  padding: 0.1rem 0.45rem;
  border: 1px solid var(--border);
  background: var(--surface-muted);
  color: var(--muted);
}

.question-group .topic__count {
  margin-left: 0;
  min-width: 8.5rem;
  padding: 0.1rem 0.55rem;
  border: 1px solid var(--border);
  background: var(--surface-muted);
}

.question-position {
  position: absolute;
  right: 0.9rem;
  bottom: 0.75rem;
  margin: 0;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 750;
}

.settings-form {
  display: grid;
  gap: 0.55rem;
  max-width: 32rem;
  padding: 1rem 1.1rem;
  border-left: 4px solid var(--accent);
  background: var(--surface);
}

.settings-field {
  display: grid;
  gap: 0.35rem;
  font-weight: 750;
}

.settings-field input {
  width: 100%;
  padding: 0.65rem 0.7rem;
  border: 1px solid var(--border);
  background: var(--surface-muted);
  color: var(--text);
  font: inherit;
}

.settings-field input:focus {
  border-color: var(--accent);
  outline: 2px solid var(--accent-soft);
}

.settings-note {
  margin: 0;
  color: var(--muted);
  font-size: 0.82rem;
}

.block-meta {
  display: grid;
  align-items: start;
  gap: 0.45rem 1rem;
  margin-top: 1rem;
  padding-top: 0.7rem;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.78rem;
}

.block-meta--section {
  margin: 0;
  padding: 0 1.1rem;
  border-top: 0;
  grid-template-columns: 1fr;
}

.block-meta__main {
  display: grid;
  gap: 0.35rem;
  min-width: 0;
}

.block-meta__row {
  display: flex;
  gap: 0.65rem;
  align-items: baseline;
}

.block-meta__label {
  flex: 0 0 auto;
  font-weight: 750;
}

.block-meta ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 0.8rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.block-meta a {
  color: var(--muted);
}
@media (max-width: 760px) {
  .comparison,
  .symbols {
    grid-template-columns: 1fr;
  }

  .study-block {
    padding: 0.9rem;
  }

  .study-block > h3:first-of-type {
    padding-right: 0;
    margin-top: 2.7rem;
  }

  .study-block--question {
    padding-bottom: 2.15rem;
  }

  .block-meta {
    grid-template-columns: 1fr;
  }

  .question-group .topic__summary {
    grid-template-columns: 1fr;
    align-items: stretch;
  }

  .question-group__meta {
    justify-items: start;
  }

  .question-group__actions {
    grid-template-columns: 1fr;
  }

  .question-group__actions .question-action,
  .question-set__actions .question-action {
    width: 100%;
  }

  .answer-check {
    align-items: stretch;
    flex-direction: column;
  }
}