:root {
  --bg:#f6f7fb;
  --card:#fff;
  --muted:#6b7280;
  --accent:#0ea5a4;
}

* {
  box-sizing: border-box;
  font-family: Inter, system-ui, Arial, sans-serif;
}

body {
  margin: 0;
  background: var(--bg);
  color: #111;
}

/* Topbar */
.topbar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 18px;
  background: linear-gradient(180deg,#fff,#f2f5f8);
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
  flex-wrap: wrap; /* allow wrapping on small screens */
}

.logo {
  width: 36px;
  height: 36px;
  border-radius: 6px;
}

.spacer {
  flex: 1;
}

/* Main split layout */
.split {
  display: flex;
  gap: 16px;
  padding: 18px;
  max-width: 1200px;
  margin: 20px auto;
}

.left, .right {
  background: var(--card);
  padding: 14px;
  border-radius: 12px;
  box-shadow: 0 6px 20px rgba(12,20,30,0.05);
}

.left {
  flex: 1;
  min-width: 320px;
}

.right {
  flex: 0.9;
  min-width: 320px;
}

/* Controls and inputs */
.controls {
  display: flex;
  gap: 8px;
  margin-bottom: 10px;
  flex-wrap: wrap;
}

textarea#questionText {
  width: 100%;
  height: 120px;
  border-radius: 8px;
  padding: 10px;
  border: 1px solid #e7e9ee;
}

.mcq-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-top: 8px;
}

.buttons {
  display: flex;
  gap: 8px;
  margin-top: 10px;
  flex-wrap: wrap;
}

button {
  background: var(--accent);
  border: none;
  color: #fff;
  padding: 8px 12px;
  border-radius: 10px;
  cursor: pointer;
}

.preview-box {
  min-height: 220px;
  border: 1px dashed #e1e6f0;
  padding: 10px;
  border-radius: 8px;
}

.question-list {
  list-style: none;
  padding: 0;
  margin: 0;
  max-height: 360px;
  overflow: auto;
}

.question-list li {
  padding: 8px 10px;
  border-bottom: 1px solid #f1f3f6;
  display: flex;
  gap: 8px;
  align-items: center;
}

.question-list li .meta {
  font-size: 12px;
  color: var(--muted);
  margin-left: auto;
}

/* Modal PDF viewer */
.modal {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.45);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
}

.modal-content {
  width: 90%;
  max-width: 1000px;
  background: var(--card);
  border-radius: 12px;
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-height: 90vh;
  overflow: hidden;
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.pdf-viewer-container {
  overflow: auto;
  background: #fff;
  padding: 8px;
  border-radius: 8px;
  height: 60vh;
  border: 1px solid #e6eef5;
}

.pdf-page {
  margin-bottom: 10px;
  position: relative;
  border: 1px solid #f1f3f6;
  padding: 6px;
}

.pdf-canvas {
  width: 100%;
  height: auto;
  display: block;
}

.pdf-textLayer {
  position: absolute;
  left: 6px;
  top: 6px;
  right: 6px;
  bottom: 6px;
  pointer-events: auto;
}

.modal-footer {
  display: flex;
  gap: 8px;
  align-items: center;
  justify-content: flex-end;
}

/* ===== Improved Mobile Responsiveness ===== */
@media (max-width: 768px) {
  body {
    font-size: 14px;
  }

  .topbar {
    flex-wrap: wrap;
    gap: 8px;
    padding: 10px;
  }

  .controls {
    flex-direction: row;
    overflow-x: auto;
    gap: 6px;
    padding-bottom: 4px;
  }

  .controls button {
    font-size: 13px;
    padding: 6px 10px;
    white-space: nowrap;
  }

  .split {
    flex-direction: column;
    padding: 10px;
    gap: 12px;
  }

  .left, .right {
    min-width: 100%;
    padding: 12px;
    box-shadow: 0 4px 14px rgba(0,0,0,0.04);
  }

  textarea#questionText {
    height: 90px;
  }

  .mcq-grid {
    grid-template-columns: 1fr;
  }

  button {
    font-size: 14px;
    padding: 8px;
  }

  .question-list {
    max-height: 260px;
  }
}