/* General Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* Page Layout */
body {
  font-family: Arial, sans-serif;
  background: #f0f6ff;
  color: #222;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

header {
  background: #0056b3;
  color: white;
  padding: 15px;
  text-align: center;
}

header h1 {
  margin-bottom: 10px;
}

.controls, .layout-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin-top: 8px;
}

.controls input, .controls button, .layout-controls input, .layout-controls button {
  padding: 8px 12px;
  border: none;
  border-radius: 6px;
  font-size: 14px;
}

.controls input {
  flex: 1;
  min-width: 150px;
}

.controls button, .layout-controls button {
  background: #007bff;
  color: white;
  cursor: pointer;
  transition: 0.3s;
}

.controls button:hover, .layout-controls button:hover {
  background: #004080;
}

/* Main Section */
main {
  display: flex;
  flex: 1;
  flex-wrap: wrap;
  padding: 20px;
  gap: 20px;
  justify-content: center;
}

#studentList, #chartArea {
  background: white;
  border-radius: 10px;
  padding: 15px;
  flex: 1 1 300px;
  min-height: 300px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

/* Student List */
#studentList ul {
  list-style: none;
  margin-top: 10px;
  max-height: 400px;
  overflow-y: auto;
}

#studentList li {
  background: #007bff;
  color: white;
  margin: 5px 0;
  padding: 6px;
  border-radius: 6px;
  cursor: grab;
}

/* Seating Chart */
#seatingChart {
  display: grid;
  gap: 10px;
  margin-top: 10px;
  justify-content: center;
}

.seat {
  width: 70px;
  height: 70px;
  background: #dce9ff;
  border: 2px dashed #007bff;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  font-size: 12px;
  text-align: center;
}

.seat.filled {
  background: #007bff;
  color: white;
  border: none;
}