* {
  margin: 0;
  padding: 0;

}

body {
  background-color: #f1f2f3;
}

.container {
  box-sizing: border-box;
  max-width: 1560px;
  min-width: 1240px;
  width: 100%;
  margin: 20px auto;
  color: #333;
}

.container *{
  box-sizing: border-box;
}

header {
  margin-bottom: 25px;
  text-align: center;
}

h1 {
  font-size: 2.1rem;
  margin-bottom: 5px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.subtitle {
  font-size: 1rem;
  opacity: 0.9;
  max-width: 95%;
  margin: 0 auto;
}

.calculator {
  display: flex;
  gap: 20px;
  margin-bottom: 25px;
}
.input-section, .result-section{
  flex: 1;
  background-color: #fff;
  padding: 20px;
  border-radius: 8px;
}

.chart-section {
  background-color: #fff;
  padding: 20px;
  border-radius: 8px;
  margin-bottom: 20px;
}

.chart-section h3{
  font-size: 1.2rem;
  margin-bottom: 15px;
}

.form-group {
  margin-bottom: 15px;
}
label {
  display: block;
  margin-bottom: 5px;
  font-weight: bold;
}
input {
  width: 100%;
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 4px;
  font-size: 16px;
}
.buttons {
  display: flex;
  gap: 10px;
  margin-top: 20px;
}
button {
  padding: 10px 15px;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-size: 14px;
  transition: background-color 0.3s;
}
.calculate-btn {
  background-color: #3498db;
  color: white;
}
.calculate-btn:hover {
  background-color: #2980b9;
}
.clear-btn {
  background-color: #e74c3c;
  color: white;
}
.clear-btn:hover {
  background-color: #c0392b;
}
.result-box {
  background-color: white;
  padding: 15px;
  border-radius: 5px;
  border: 1px solid #ddd;
  min-height: 120px;
  margin-top: 10px;
}
.formula {
  font-family: 'Times New Roman', serif;
  font-size: 18px;
  margin: 15px 0;
  text-align: center;
}
.error {
  color: #e74c3c;
  font-weight: bold;
}
canvas {
  width: 100%;
  height: 350px;
  background-color: white;
  border-radius: 5px;
  border: 1px solid #ddd;
}

.instructions {
  background-color: #f9f9f9;
  padding: 20px;
  border-radius: 5px;
  margin-bottom: 20px;
  border-left: 4px solid #e67e22;
}

.instructions p{
  opacity: 0.9;
  margin-top: 8px;
}

.instructions ul{
  margin-left: 20px;
  margin-top: 8px;
  line-height: 1.7;
}