:root {
  --primary: #2c3e50;
  --accent: #27ae60;
  --bg: #f4f7f6;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: var(--bg);
  color: #333;
  line-height: 1.6;
  margin: 0;
  padding: 20px;
}

.container {
  max-width: 600px;
  margin: 20px auto;
  background: #fff;
  padding: 30px;
  border-radius: 12px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

h1,
h2,
h3 {
  color: var(--primary);
}

input {
  width: 100%;
  padding: 12px;
  margin: 15px 0;
  border: 2px solid #ddd;
  border-radius: 8px;
  font-size: 16px;
  box-sizing: border-box;
}

button {
  width: 100%;
  padding: 12px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 18px;
  cursor: pointer;
  transition: 0.3s;
}

button:hover {
  background: #1a252f;
}

.result-box {
  margin-top: 25px;
  padding: 20px;
  border-radius: 8px;
  background: #f9f9f9;
  border-left: 5px solid var(--accent);
  display: none;
}

.row {
  display: flex;
  justify-content: space-between;
  margin-bottom: 10px;
  border-bottom: 1px dashed #eee;
  padding-bottom: 5px;
}

.total {
  font-weight: bold;
  font-size: 1.2em;
  color: var(--accent);
  border: none;
}

.footer {
  text-align: center;
  margin-top: 40px;
  font-size: 0.9em;
  color: #777;
}

.faq-section {
  margin-top: 30px;
  border-top: 1px solid #eee;
  padding-top: 20px;
}