body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  margin: 0;
  padding: 0;
  min-height: 100vh;
  position: relative;
  background: linear-gradient(120deg, #0050ac 0%, #54b98d 90%);
  background-attachment: fixed;
  overflow-x: hidden;
}

#background {
  position: fixed;
  z-index: 0;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(120deg, #0050ac 0%, #54b98d 80%);
}

#center {
  min-height: 100vh;
  min-width: 100vw;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1;
  position: relative;
}

#app {
  background: white;
  color: #333;
  max-width: 670px;
  width: 95vw;
  padding: 36px 32px 32px 32px;
  border-radius: 13px;
  box-shadow: 0 8px 36px rgba(60, 27, 120, 0.18), 0 1.5px 8px rgba(107, 60, 174, 0.05);
  margin: 40px 0;
  position: relative;
}

h1 {
  font-size: 2.2rem;
  text-align: center;
  margin: 0 0 22px 0;
  font-weight: 800;
  color: #178a58;
  letter-spacing: 0.5px;
}

h2, h3 {
  font-size: 1.2rem;
  text-align: center;
  color: #178a58;
  margin: 0 0 18px 0;
  font-weight: 700;
}

/* Question Highlighting */
code {
  text-align: start;
  font-size: 1rem;
  font-weight: 500;
  border: 1px solid #ddd;
  border-radius: 6px;
  vertical-align: baseline;
  line-height: 1;
}

/*Question option highlighting*/
input + div > pre > code, .incorrect-review-block > div > pre > code {
  display: inline !important;
  white-space: pre-line !important;
  border: none !important;
  padding: 0 !important;
}

input + div > pre, .incorrect-review-block > div > pre {
  display: inline-block !important;
  margin: 0 !important;
}

h3 {
  color: #888;
  font-size: 1.09rem;
  font-weight: 500;
  margin-top: 33px;
}

button {
  display: inline-block;
  background: linear-gradient(92deg, #54b98d 65%, #0050ac 180%);
  color: white;
  border: none;
  padding: 14px 28px;
  margin: 14px 10px 18px 0;
  border-radius: 6px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: 0.22s all cubic-bezier(.23,1.08,.87,.68);
  box-shadow: 0 4px 12px rgba(102, 48, 175, 0.11);
}

button:hover {
  background: linear-gradient(92deg, #54b98d 50%, #83bcfa 180%);
  filter: brightness(110%);
  box-shadow: 0 10px 28px rgba(17, 142, 98, 0.16);
  transform: translateY(-1.7px) scale(1.04);
}

/* Botón de terminar examen temprano */
.finish-early-btn {
  background-color: #b23b3b;
  color: white;
  border-radius: 6px;
  padding: 12px 20px;
  font-weight: 600;
  margin-top: 10px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.2);
}
.finish-early-btn:hover {
  background-color: #a12727;
}

label {
  margin-bottom: 10px;
  font-size: 1rem;
  cursor: pointer;
  user-select: none;
  display: flex;
  align-items: center;
}

label > div {
  display: inline;
}

input[type="radio"],
input[type="checkbox"] {
  margin-right: 12px;
  cursor: pointer;
  accent-color: #54b98d;
  display: inline;
  flex-shrink: 0;
}

.multi-answer-msg {
  font-weight: 600;
  color: #0050ac;
  font-size: 1.05rem;
  margin-bottom: 10px;
  text-align: center;
}

/* ========= NUEVO: BLOQUES Y ETIQUETAS RESALTADAS EN REVIEW ========= */
.incorrect-review-block {
  background: #e6f0ff;
  border: 2.5px solid #2186e7;
  border-radius: 11px;
  padding: 18px 18px 0px 18px;
  margin: 20px 0 25px 0;
  font-size: 1.08rem;
  box-shadow: 0 2.5px 10px #b4d4f7c0;
  letter-spacing: 0.08px;
}

.rev-label {
  display: block;
  margin-top: 7px;
  font-weight: bold;
  color: #273d63;
  margin-bottom: 3px;
  letter-spacing: 0.06em;
}

.rev-label.question { color: #0a2e73; }
.rev-label.your { color: #a5324d; }
.rev-label.correct { color: #257a1b; }
.rev-label.explanation { color: #54b98d; }

/* Botones juntos pero separados en examen */
.exam-btns-wrapper {
  display: flex;
  align-items: center;
  margin-top: 18px;
  margin-bottom: 10px;
  gap: 14px;
}
.exam-btns-wrapper .finish-early-btn {
  margin-left: auto;
}
.question-nav-buttons {
  position: fixed;
  bottom: 32px;
  right: 32px;
  display: flex;
  gap: 16px;
  z-index: 10;
}

.nav-arrow-btn {
  font-size: 2rem;
  padding: 8px 16px;
  background: #0e1726;
  color: #fff;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 2px 12px rgba(0,0,0,0.10);
  transition: background 0.2s;
}
.nav-arrow-btn:hover {
  background: #26396c;
}

/* MIT License Compliance */
.fork-label {
  position: absolute;
  right: 14px;
  bottom: 12px;
  font-size: 0.78rem;
  color: rgba(0,0,0,0.65);
  background: rgba(255,255,255,0.92);
  padding: 6px 8px;
  border-radius: 6px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.08);
  z-index: 5;
  opacity: 0.85;
}

.fork-label a {
  color: #0e56a6;
  text-decoration: none;
  font-weight: 600;
}

.fork-label a:hover {
  text-decoration: underline;
  color: #083e78;
}