/* La interfaz comparte styles.css con la portada; la impresión usa el CSS original. */
:root {
  --blue: var(--accent);
  --blue-dark: var(--accent);
  --canvas: var(--bg);
  --surface: color-mix(in srgb, var(--ink) 2%, var(--bg));
  background: var(--bg);
}

.exercises-page {
  overflow: auto;
  background-attachment: fixed;
}

.exercises-page .site-header {
  position: relative;
  background: transparent;
  border: 0;
  line-height: normal;
}

.exercises-page #contenido {
  width: min(980px, calc(100% - 64px));
  margin-inline: auto;
  padding: 12px 0 64px;
}

.exercises-page .skip-link {
  z-index: 20;
  border: 1px solid var(--accent);
  border-radius: 8px;
  color: var(--ink);
  background: var(--bg);
}

.exercises-page .back-link {
  margin: 12px 0 32px;
  color: var(--muted);
  font-size: .78rem;
  font-weight: 450;
}

.exercises-page .back-link:hover {
  color: var(--ink);
}

.exercises-page.index-page .results-heading {
  align-items: baseline;
  flex-wrap: wrap;
  gap: 10px 24px;
  padding: 0 0 26px;
}

.exercises-page.index-page .results-heading h1 {
  margin: 0;
  color: var(--ink);
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 450;
  letter-spacing: -.04em;
  line-height: 1.25;
}

.exercises-page .results-count {
  margin-left: auto;
  font-size: .78rem;
  white-space: nowrap;
}

.exercises-page.index-page #contenido {
  max-width: 820px;
}

.exercises-page .exercise-list {
  border-top: 1px solid var(--line);
}

.exercises-page .exercise-item {
  border-bottom: 1px solid var(--line-soft);
  border-radius: 8px;
  transition: background 160ms ease;
}

.exercises-page .exercise-item .task-link {
  min-height: 64px;
  padding: 18px 16px 18px 8px;
  border-radius: 8px;
  color: var(--ink);
  font-size: 1rem;
  font-weight: 450;
  line-height: 1.5;
  transition: color 160ms ease;
}

.exercises-page .exercise-item:hover,
.exercises-page .exercise-item:focus-within,
.exercises-page .exercise-item:has(.pdf-select:checked) {
  background: color-mix(in srgb, var(--accent) 7%, transparent);
}

.exercises-page .exercise-item .task-link:hover {
  color: var(--accent);
}

.exercises-page .exercise-item .task-link:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: -2px;
}

.exercises-page .task-arrow {
  width: 18px;
  height: 18px;
  color: var(--muted);
  transition: color 160ms ease, transform 160ms ease;
}

.exercises-page .task-link:hover .task-arrow {
  color: var(--accent);
  transform: translateX(3px);
}

.exercises-page .exercise-select input,
.exercises-page .pdf-select-all input {
  appearance: none;
  display: grid;
  flex: none;
  width: 16px;
  height: 16px;
  margin: 0;
  border: 1px solid var(--muted);
  border-radius: 4px;
  background: transparent;
  place-items: center;
  cursor: pointer;
}

.exercises-page .exercise-select input:checked,
.exercises-page .pdf-select-all input:checked,
.exercises-page .pdf-select-all input:indeterminate {
  border-color: var(--accent);
  background: var(--accent);
}

.exercises-page .exercise-select input:checked::after,
.exercises-page .pdf-select-all input:checked::after {
  width: 8px;
  height: 5px;
  margin-top: -2px;
  border-bottom: 2px solid var(--bg);
  border-left: 2px solid var(--bg);
  content: "";
  transform: rotate(-45deg);
}

.exercises-page .pdf-select-all input:indeterminate::after {
  width: 8px;
  border-bottom: 2px solid var(--bg);
  content: "";
}

.exercises-page .exercise-select input:focus-visible,
.exercises-page .pdf-select-all input:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
}

.exercises-page .pdf-select-all {
  color: var(--muted);
  font-size: .78rem;
}

.exercises-page .pdf-select-all:hover {
  color: var(--ink);
}

.exercises-page .pdf-toolbar {
  gap: 12px;
  margin-top: 20px;
}

.exercises-page .button {
  min-height: 44px;
  padding: 10px 18px;
  border-color: color-mix(in srgb, var(--accent) 32%, transparent);
  border-radius: 8px;
  color: var(--ink);
  background: color-mix(in srgb, var(--accent) 20%, var(--bg));
  font-size: .8rem;
  font-weight: 650;
  transition: background 160ms ease, border-color 160ms ease;
}

.exercises-page .button:not(:disabled):hover {
  border-color: var(--accent);
  background: color-mix(in srgb, var(--accent) 30%, var(--bg));
}

.exercises-page .button:disabled,
.exercises-page .pdf-clear:disabled {
  opacity: .4;
  cursor: default;
}

.exercises-page .pdf-clear {
  min-height: 44px;
  color: var(--muted);
  font-size: .78rem;
  text-underline-offset: 4px;
}

.exercises-page .pdf-clear:not(:disabled):hover {
  color: var(--ink);
}

.exercises-page .pdf-toolbar p {
  margin-top: 2px;
  color: var(--muted);
  font-size: .72rem;
}

.exercises-page .task-layout {
  grid-template-columns: minmax(0, 1fr) 210px;
  gap: 52px;
}

.exercises-page .task-main {
  padding: 0;
  border: 0;
  border-radius: 0;
  background: transparent;
}

.exercises-page .task-main .eyebrow {
  margin-bottom: 14px;
  color: var(--accent);
  font-size: .66rem;
  font-weight: 650;
  letter-spacing: .14em;
  text-transform: uppercase;
}

.exercises-page .task-main h1 {
  margin-bottom: 30px;
  color: var(--ink);
  font-size: clamp(1.7rem, 3.2vw, 2.35rem);
  font-weight: 450;
  letter-spacing: -.04em;
  line-height: 1.25;
}

.exercises-page .task-main h2 {
  margin: 28px 0 20px;
  padding-top: 22px;
  border-color: var(--line);
  color: var(--muted);
  font-size: .68rem;
  font-weight: 650;
  letter-spacing: .13em;
  text-transform: uppercase;
}

.exercises-page .instructions {
  color: var(--ink);
  font-size: .96rem;
  line-height: 1.85;
}

/* Enunciados ampliados: lectura continua, con la jerarquía en los títulos. */
.exercises-page .authored-instructions {
  font-size: 1rem;
  line-height: 1.75;
}

.exercises-page .authored-instructions .exercise-block {
  margin: 36px 0;
  padding: 0;
  border: 0;
  border-radius: 0;
  background: transparent;
  box-shadow: none;
}

.exercises-page .authored-instructions .exercise-block-header {
  margin-bottom: 16px;
}

.exercises-page .authored-instructions .exercise-block h3 {
  margin-bottom: 16px;
  font-weight: 650;
  line-height: 1.4;
}

.exercises-page .instructions a {
  color: var(--accent);
  text-underline-offset: 4px;
}

.exercises-page .instructions img {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: white;
}

.exercises-page .instructions pre {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.exercises-page .instructions td,
.exercises-page .instructions th {
  border-color: var(--line);
}

.exercises-page .task-download {
  position: sticky;
  top: 32px;
}

.exercises-page .attachment-link {
  border-color: var(--line);
  border-radius: 10px;
  color: var(--ink);
  background: var(--surface);
}

.exercises-page .attachment-link:hover {
  border-color: color-mix(in srgb, var(--accent) 50%, var(--line));
  background: color-mix(in srgb, var(--accent) 7%, var(--bg));
}

.exercises-page .attachment-link > svg {
  color: var(--accent);
}

.exercises-page .attachment-link strong {
  font-weight: 500;
}

.exercises-page .task-main > .subtle {
  font-size: .82rem;
}

@media (max-width: 800px) {
  .exercises-page .task-layout {
    display: flex;
    flex-direction: column;
    gap: 28px;
  }

  .exercises-page .task-download {
    position: static;
    width: 100%;
  }
}

@media (max-width: 720px) {
  .exercises-page #contenido {
    width: calc(100% - 40px);
    padding: 8px 0 40px;
  }

  .exercises-page .back-link {
    margin: 8px 0 28px;
  }

  .exercises-page .exercise-select {
    flex-basis: 44px;
  }

  .exercises-page .exercise-item .task-link {
    gap: 16px;
    padding: 16px 10px 16px 4px;
    font-size: .94rem;
  }

  .exercises-page .pdf-toolbar .button {
    width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  .exercises-page .exercise-item,
  .exercises-page .exercise-item .task-link,
  .exercises-page .task-arrow {
    transition: none;
  }
}

@media (forced-colors: active) {
  .exercises-page .exercise-select input,
  .exercises-page .pdf-select-all input {
    appearance: auto;
  }

  .exercises-page .exercise-select input::after,
  .exercises-page .pdf-select-all input::after {
    display: none;
  }
}