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

body {
  background: #f2f2f2;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  position: relative;
}

#historyBtn {
  position: absolute;
  top: 20px;
  right: 20px;
  padding: 10px 15px;
  background: #007bff;
  color: white;
  border: none;
  border-radius: 5px;
  font-size: 14px;
  cursor: pointer;
  height: 28px;
  width: 100px;
}

#historyBtn:hover {
  background: #0056b3;
}

.container {
  background: #ffffff;
  padding: 25px;
  border-radius: 10px;
  width: 320px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

h1 {
  text-align: center;
  margin-bottom: 20px;
}

.field {
  margin-bottom: 15px;
}

label {
  display: block;
  margin-bottom: 5px;
  font-weight: bold;
}

input, select {
  width: 100%;
  padding: 8px;
  border-radius: 5px;
  border: 1px solid #ccc;
}

button {
  width: 100%;
  padding: 10px;
  background: #007bff;
  color: white;
  border: none;
  border-radius: 5px;
  font-size: 16px;
  cursor: pointer;
}

button:hover {
  background: #0056b3;
}

#result {
  margin-top: 15px;
  text-align: center;
  font-weight: bold;
}

/* History Popup */
.popup {
  display: none;
  position: fixed;
  z-index: 1;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  overflow: auto;
  background-color: rgba(0,0,0,0.4);
}

.popup-content {
  background-color: #fefefe;
  margin: 15% auto;
  padding: 20px;
  border: 1px solid #888;
  width: 80%;
  max-width: 600px;
  border-radius: 10px;
}

.close {
  color: #aaa;
  float: right;
  font-size: 28px;
  font-weight: bold;
  cursor: pointer;
}

.close:hover,
.close:focus {
  color: black;
  text-decoration: none;
}

#historyList {
  max-height: 400px;
  overflow-y: auto;
}

.history-item {
  border-bottom: 1px solid #ddd;
  padding: 10px 0;
}

.history-item:last-child {
  border-bottom: none;
}