* { box-sizing: border-box; }

:root {
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #1f2937;
  background: #eef2f7;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body { margin: 0; min-height: 100vh; }
button, input, textarea { font: inherit; }

.app-header {
  padding: 24px clamp(20px, 5vw, 64px);
  background: #fff;
  border-bottom: 1px solid #dbe3ec;
}
.app-header h1 { margin: 0 0 6px; font-size: clamp(1.6rem, 3vw, 2.3rem); }
.app-header p { margin: 0; color: #52606d; }

.app-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(360px, .8fr);
  gap: 24px;
  padding: 24px clamp(20px, 5vw, 64px) 48px;
  align-items: start;
}
.editor-panel, .preview-panel { min-width: 0; }

.card {
  background: #fff;
  border: 1px solid #dbe3ec;
  border-radius: 14px;
  box-shadow: 0 8px 24px rgba(31, 41, 55, .06);
}
.worksheet-settings, .question-card { padding: 20px; }
.worksheet-settings h2, .section-heading h2 { margin-top: 0; }

label { display: grid; gap: 7px; font-weight: 650; margin-bottom: 16px; }
input[type="text"], textarea {
  width: 100%; border: 1px solid #b9c5d3; border-radius: 9px;
  padding: 11px 12px; background: #fff;
}
textarea { resize: vertical; }
input[type="text"]:focus, textarea:focus {
  outline: 3px solid rgba(37, 99, 235, .16); border-color: #2563eb;
}
.two-column { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.checkbox-row { display: flex; align-items: center; gap: 10px; margin: 0; }
.section-heading { margin-top: 24px; display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.question-card { margin-bottom: 16px; }
.question-card-header { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-bottom: 14px; }
.question-card-header h3 { margin: 0; }
.answers-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.answer-editor { margin: 0; }
.answer-editor > span { display: flex; align-items: center; gap: 8px; }
.correct-answer-help { margin: 14px 0 0; color: #667085; font-size: .9rem; }

button { border: 0; border-radius: 9px; padding: 10px 14px; cursor: pointer; font-weight: 700; }
.primary-button { background: #2563eb; color: #fff; }
.primary-button:hover { background: #1d4ed8; }
.secondary-button { background: #e7eef8; color: #1e3a5f; }
.secondary-button:hover { background: #d9e4f2; }
.remove-question-button { background: #fee2e2; color: #991b1b; padding: 8px 11px; }
.add-question-row { display: flex; justify-content: flex-start; margin: 8px 0 18px; }
.action-bar {
  position: sticky; bottom: 0; display: flex; flex-wrap: wrap; gap: 10px;
  padding: 16px 0 4px; background: linear-gradient(to top, #eef2f7 78%, transparent);
}

.preview-panel { position: sticky; top: 20px; }
.preview-label { margin-bottom: 8px; color: #52606d; font-weight: 750; }
.worksheet-page {
  position: relative; isolation: isolate; overflow: hidden;
  width: 100%; min-height: 1050px; background: #fff; padding: 44px;
  box-shadow: 0 12px 32px rgba(31, 41, 55, .13); color: #111827;
}
.worksheet-content { position: relative; z-index: 1; }
.watermark-layer {
  position: absolute; z-index: 0; inset: -120px; overflow: hidden;
  display: grid; grid-template-columns: repeat(5, 230px); grid-auto-rows: 115px;
  align-items: center; justify-items: center; transform: rotate(-45deg);
  pointer-events: none; user-select: none;
  color: rgba(100, 116, 139, .14); font-size: 20px; font-weight: 500;
  white-space: nowrap;
}
.preview-title {
  text-align: center; margin: 0 0 10px; font: bold 2em/1.2 Georgia, "Times New Roman", serif;
}
.preview-subtitle {
  text-align: center; margin: 0 0 28px; font: normal 1rem/1.4 Georgia, "Times New Roman", serif;
  color: #374151;
}
.student-lines { display: grid; grid-template-columns: 1fr .7fr; gap: 32px; margin-bottom: 30px; }
.student-line { border-bottom: 1px solid #111827; padding-bottom: 4px; }
.preview-question {
  margin: 0 0 22px;
  break-inside: avoid-page;
  page-break-inside: avoid;
}
.preview-question-text {
  display: block;
  margin: 0 0 10px;
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.35;
  overflow-wrap: anywhere;
  word-break: normal;
}
.preview-answers { display: grid; grid-template-columns: 1fr 1fr; gap: 7px 24px; padding-left: 20px; }
.preview-answer { font-size: 1rem; line-height: 1.4; overflow-wrap: anywhere; }
.answer-key { margin-top: 40px; padding-top: 24px; border-top: 2px solid #111827; break-before: page; page-break-before: always; }
.answer-key h2 { text-align: center; }
.answer-key-list { columns: 3; column-gap: 32px; }
.empty-preview { color: #667085; text-align: center; margin-top: 80px; }

@media (max-width: 1000px) {
  .app-layout { grid-template-columns: 1fr; }
  .preview-panel { position: static; }
}
@media (max-width: 620px) {
  .two-column, .answers-grid, .student-lines, .preview-answers { grid-template-columns: 1fr; }
  .worksheet-page { padding: 28px 22px; }
}

@media print {
  :root, body { background: #fff; -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
  .app-header, .editor-panel, .preview-label { display: none !important; }
  .app-layout { display: block; padding: 0; }
  .preview-panel { position: static; }
  .worksheet-page {
    box-shadow: none; width: auto; min-height: 0; padding: 0;
    overflow: visible; font-size: 11pt;
  }
  .watermark-layer {
    position: fixed;
    inset: -1in;
    color: rgba(100, 116, 139, .13);
    font-size: 18pt;
    -webkit-print-color-adjust: exact;
    print-color-adjust: exact;
  }
  .preview-title { font-size: 20pt !important; line-height: 1.2 !important; }
  .preview-subtitle { font-size: 11pt !important; line-height: 1.35 !important; }
  .preview-question {
    break-inside: avoid-page !important;
    page-break-inside: avoid !important;
  }
  .preview-question-text {
    font-size: 11pt !important;
    line-height: 1.3 !important;
    margin: 0 0 7pt !important;
    max-width: 100%;
    overflow: visible;
  }
  .preview-answer { font-size: 10.5pt !important; line-height: 1.35 !important; }
  @page { size: A4; margin: .55in; }
}