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

body {
  margin: 0;
  min-height: 100vh;
  background: linear-gradient(135deg, #e8f5e9, #f1f8e9);
  display: flex;
  justify-content: center;
  align-items: center;
}

main {
  background: white;
  padding: 30px 40px;
  border-radius: 16px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
  width: 360px;
  text-align: center;
}

/* ===== RANDOM NUMBER ===== */

.random_box h2 {
  margin-bottom: 10px;
}

#random_namer {
  font-size: 36px;
  font-weight: bold;
  margin-bottom: 20px;
  color: #2e7d32;
}

/* ===== BUTTON ===== */

.btn {
  margin-bottom: 20px;
}

#btn {
  width: 100%;
  height: 50px;
  background: #43a047;
  color: white;
  font-size: 18px;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  box-shadow: 0 4px 0 #2e7d32;
  transition: transform 0.1s, box-shadow 0.1s;
}

#btn:hover {
  filter: brightness(1.05);
}

#btn:active {
  transform: translateY(4px);
  box-shadow: 0 0 0 #2e7d32;
}

/* ===== FROM / TO ===== */

.from-to {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 20px;
}

.from-to label {
  font-weight: bold;
  text-align: left;
}

.from-to input {
  padding: 8px;
  font-size: 16px;
  border-radius: 6px;
  border: 1px solid #ccc;
}

/* ===== SAVE ===== */

#txt {
  width: 100%;
  padding: 8px;
  margin-bottom: 10px;
  border-radius: 6px;
  border: 1px solid #ccc;
}

#save_number {
  width: 100%;
  height: 40px;
  background: #eeeeee;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  font-size: 14px;
}

#save_number:hover {
  background: #e0e0e0;
}