/* src/index.css */
:root {
  --paper: #f6f2ea;
  --paper-strong: #ede6d8;
  --ink: #28231b;
  --muted: #6c6457;
  --line: #d7ccba;
  --accent: #145d6a;
  --panel-off: #dedbd4;
}

* {
  box-sizing: border-box;
}

body {
  color: var(--ink);
  background: radial-gradient(circle at 20% 10%, #fbf8f1 0%, #f0e8da 50%, #e6ddce 100%), linear-gradient(160deg, #f7f2e8 0%, #ece1d1 100%);
  margin: 0;
  font-family: IBM Plex Sans, Trebuchet MS, Segoe UI, sans-serif;
}

h1, h2 {
  margin: 0;
  font-family: Bitter, Georgia, Times New Roman, serif;
}

p {
  margin: 0;
}

button, textarea {
  font: inherit;
}

.app {
  min-height: 100vh;
  padding: 1.2rem;
}

.header {
  display: flex;
  border: 1px solid var(--line);
  background: #ffffffa8;
  border-radius: .8rem;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem;
}

.eyebrow {
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: .08em;
  margin-bottom: .4rem;
  font-size: .78rem;
  font-weight: 700;
}

.header-actions {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
}

.header-actions button {
  cursor: pointer;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: .5rem;
  padding: .45rem .7rem;
}

.save-button {
  display: inline-flex;
  align-items:  center;
  gap: .4rem;
}

.workspace {
  margin-top: 1rem;
}

.variants-scroll {
  overflow-x: auto;
}

.variants-row {
  display: flex;
  align-items: stretch;
  gap: 1rem;
  min-width: max-content;
}

.sections-grid {
  display: grid;
  grid-template-columns: 26rem 26rem 4.1rem;
  align-items: stretch;
  gap: .9rem 1rem;
  min-width: max-content;
}

.variant-title {
  padding: .1rem .2rem;
  font-size: 1.12rem;
}

.title-with-preview {
  display: flex;
  align-items:  center;
  gap: .55rem;
}

.preview-button {
  color: var(--muted);
  cursor: pointer;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: .4rem;
  padding: .3rem .55rem;
  font-size: .82rem;
}

.variant {
  display: grid;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: .8rem;
  gap: .9rem;
  width: 26rem;
  padding: 1rem;
}

.preview-only {
  margin: 0 auto;
}

.variant-slot {
  display: grid;
  width: 26rem;
  min-width: 26rem;
}

.variant-slot.empty {
  height: 100%;
}

.add-rail {
  display: grid;
  background: #dedbd4bf;
  border-radius: .8rem;
  align-self: stretch;
  place-items:  center;
  width: 4.1rem;
  min-width: 4.1rem;
  padding: .5rem;
}

.add-rail.spacer {
  background: #dedbd473;
}

.variant h2 {
  font-size: 1.12rem;
}

.block {
  background: #fff;
  border-radius: .55rem;
  padding: .8rem;
}

.section-text {
  white-space: pre-line;
  line-height: 1.5;
}

.exercise {
  display: grid;
  gap: .6rem;
}

.exercise-prompt {
  font-weight: 700;
}

.exercise-answer {
  color: var(--muted);
  font-size: .9rem;
}

.fraction {
  display: inline-grid;
  grid-template-rows: auto 1px auto;
  vertical-align: middle;
  justify-items: center;
  min-width: 1.8rem;
  line-height: 1;
}

.fraction-line {
  background: currentColor;
  width: 100%;
}

.comparison-list, .choice-pairs {
  display: grid;
  gap: .55rem;
  margin: 0;
  padding-left: 1.4rem;
}

.comparison-list li, .choice-pairs li {
  display: flex;
  align-items:  center;
  gap: .55rem;
}

.grouped-choices li {
  flex-wrap: wrap;
  row-gap: .35rem;
}

.exercise-subtitle {
  width: 100%;
  font-weight: 700;
}

.answer-box {
  letter-spacing: .02em;
  font-weight: 700;
}

.or-text {
  color: var(--muted);
}

ol {
  display: grid;
  gap: .35rem;
  margin: 0;
  padding-left: 1.4rem;
}

.correct {
  color: var(--accent);
  font-weight: 700;
}

.plus {
  color: #fff;
  cursor: pointer;
  background: linear-gradient(145deg, #145d6a, #1a7685);
  border: none;
  border-radius: 999px;
  width: 3rem;
  height: 3rem;
  font-size: 1.6rem;
  line-height: 1;
}

.ghost {
  position: relative;
  color: #9a9285;
  background: linear-gradient(#ece8df 0%, #e4dfd4 100%);
  border: 1px dashed #c8beae;
  height: 100%;
}

.ghost .plus {
  position: absolute;
  margin: auto;
  inset: 0;
}

.ghost.active .plus {
  margin: 0;
  inset: .9rem .9rem auto auto;
}

.ghost-note {
  color: #887f73;
  text-align: center;
  font-size: .95rem;
}

.menu {
  display: grid;
  background: #fff;
  border-radius: .7rem;
  gap: .55rem;
  padding: .8rem;
}

.controls-tray {
  display: grid;
  gap: .6rem;
  width: 26rem;
  margin-top: .75rem;
}

.controls-tray.active {
  background: #dedbd48c;
  border-radius: .8rem;
  padding: .7rem;
}

.menu textarea {
  resize: vertical;
  border: 1px solid var(--line);
  border-radius: .45rem;
  width: 100%;
  min-height: 6rem;
  padding: .55rem;
}

.suggestions {
  display: flex;
  flex-wrap: wrap;
  gap: .45rem;
}

.suggestions button, .generate {
  cursor: pointer;
  border-radius: .45rem;
  padding: .4rem .6rem;
}

.suggestions button {
  border: 1px solid var(--line);
  background: #fff;
}

.generate {
  color: #fff;
  background: linear-gradient(145deg, #145d6a, #1a7685);
  border: none;
}

.generate:disabled {
  cursor: not-allowed;
  opacity: .65;
}

.status {
  color: var(--muted);
  font-size: .92rem;
}

.toast {
  position: fixed;
  color: #8f3e20;
  background: #fff3ec;
  border: 1px solid #e2c7b8;
  border-radius: .55rem;
  max-width: 20rem;
  padding: .65rem .85rem;
  bottom: 1rem;
  right: 1rem;
}

@media (max-width: 960px) {
  .variant {
    width: min(26rem, 100vw - 2.4rem);
  }

  .sections-grid {
    grid-template-columns: min(26rem, calc(100vw - 2.4rem)) min(26rem, calc(100vw - 2.4rem)) min(26rem, calc(100vw - 2.4rem));
  }

  .variant-slot, .add-rail, .controls-tray {
    width: min(26rem, 100vw - 2.4rem);
    min-width: min(26rem, 100vw - 2.4rem);
  }
}