body {
  font-family: "Segoe UI", sans-serif;
  background: linear-gradient(135deg, #0d6efd, #6f42c1);
  margin: 0;
  padding: 20px;
}

.container {
  max-width: 750px;
  margin: auto;
  background: white;
  padding: 30px;
  border-radius: 12px;
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
}

h2 {
  text-align: center;
  color: #0d6efd;
  margin-bottom: 20px;
}

label {
  font-weight: 600;
  margin-top: 12px;
  display: block;
}

input,
textarea {
  width: 100%;
  padding: 12px;
  margin-top: 6px;
  border-radius: 6px;
  border: 1px solid #ccc;
  font-size: 15px;
}

input:valid {
  border-color: green;
}

input:invalid {
  border-color: red;
}

.sessions {
  background: #f8f9fa;
  padding: 15px;
  border-radius: 8px;
  margin-top: 10px;
}

.sessions label {
  font-weight: normal;
  margin-bottom: 8px;
  display: block;
}

.total {
  margin-top: 15px;
  font-size: 18px;
  font-weight: bold;
  color: #198754;
}

button {
  width: 100%;
  padding: 12px;
  font-size: 16px;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  margin-top: 12px;
}

.add-btn {
  background: #198754;
  color: white;
}

.submit-btn {
  background: #0d6efd;
  color: white;
}

button:hover {
  opacity: 0.9;
}

select {
  width: 100%;
  padding: 12px;
  margin-top: 6px;
  border-radius: 6px;
  border: 1px solid #ccc;
  font-size: 15px;
}

/* Disabled / default option look */
select option[value=""] {
  color: #6c757d;
}

.note {
  font-size: 13px;
  color: #6c757d;
  margin-top: 10px;
}

.output {
  margin-top: 30px;
  padding: 20px;
  background: #f1f5ff;
  border-left: 5px solid #0d6efd;
  border-radius: 8px;
}

.output h3 {
  color: #0d6efd;
}

.output ul {
  padding-left: 20px;
}