/* 口诀标签样式 */
.formula-tag {
  cursor: pointer;
  padding: 4px 8px;
  background-color: #cfe2ff;
  color: #0d6efd;
  border-radius: 4px;
  margin-right: 8px;
  transition: all 0.2s;
}

.formula-tag:hover {
  background-color: #0d6efd;
  color: white;
}

/* 模态框样式 */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: 1000;
  justify-content: center;
  align-items: center;
  padding: 20px;
}

.modal-content {
  background-color: white;
  padding: 20px;
  border-radius: 8px;
  max-width: 90%;
  max-height: 90%;
  overflow-y: auto;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.close-btn {
  float: right;
  font-size: 20px;
  cursor: pointer;
  padding: 0 8px;
}

.formula-table {
  margin-top: 15px;
}

.formula-row {
  display: flex;
  margin-bottom: 2px;
}

.formula-item {
  width: 60px;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid #333;
  margin-right: 2px;
  font-size: 14px;
}

/* 除法样式 */
.division-bar {
  position: relative;
  display: inline-block;
  padding-left: 24px;
}

.division-bar::before {
  content: "";
  position: absolute;
  top: 0;
  left: 12px;
  width: 2px;
  height: 100%;
  background: #000;
}

.division-bar::after {
  content: "";
  position: absolute;
  top: 0;
  left: 12px;
  width: calc(150%);
  height: 2px;
  background: #000;
}

.carry-digit {
  color: #ff0000;
  font-weight: bold;
}

.divisor {
  position: absolute;
  left: -20px;
  top: 0;
  line-height: 1;
}

.full-dividend {
  position: relative;
  z-index: 10;
}

.group-2 {
  margin-left: 0.5rem;
}

.group-3 {
  margin-left: 1rem;
}

.group-4 {
  margin-left: 1.5rem;
}

.partial-product-1 {
  margin-left: calc(40px * 1.5);
}

.partial-product-2 {
  margin-left: calc(40px * -0.5);
}

.partial-product-3 {
  margin-left: calc(40px * -2.5);
}

.partial-product-4 {
  margin-left: calc(40px * -4.5);
}

.partial-product-5 {
  margin-left: 40px;
}

.partial-product-1,
.partial-product-2,
.partial-product-3,
.partial-product-4,
.partial-product-5 {
  letter-spacing: 25px;
}

#vertical {
  text-align: center;
}

.multiplicand-digit {
  display: inline-block;
  width: 40px;
  text-align: right;
  position: relative;
}

.multiplier-digit {
  display: inline-block;
  width: 40px;
  text-align: right;
  position: relative;
}

.multiplication-vertical .carry {
  position: absolute;
  left: 5px;
  bottom: -50px;
  color: #ff0000;
  font-weight: bold;
  font-size: 1rem;
}

.multiplication-line {
  /* 横线样式 */
  border-bottom: 2px solid #000;
  margin: 8px 0;
  width: 400px;
  margin-left: 40px;
}

.partial-product {
  margin-left: 80px;
}

.partial-product.second {
  margin-left: 40px;
}

.multiplication-result {
  margin-left: calc(40px * 0.6);
  font-weight: bold;
  letter-spacing: 25px;
}