:root {
  --bg-gradient: linear-gradient(135deg, #4e73df, #1cc88a);
  --container-bg: transparent;
  --text-color: #ffffff;
  --button-bg: #f6c23e;
  --button-text: #000000;
  --card-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
  --toggle-bg: rgba(255, 255, 255, 0.2);
}

[data-theme="light"] {
  --bg-gradient: linear-gradient(135deg, #f8f9fc, #e3e6f0);
  --container-bg: #ffffff;
  --text-color: #4e73df;
  --button-bg: #4e73df;
  --button-text: #ffffff;
  --card-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
  --toggle-bg: rgba(0, 0, 0, 0.1);
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  text-align: center;
  margin: 0;
  padding: 0;
  background: var(--bg-gradient);
  color: var(--text-color);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  transition: background 0.3s ease, color 0.3s ease;
}

.theme-toggle {
  position: absolute;
  top: 20px;
  right: 20px;
  padding: 10px 20px;
  border-radius: 20px;
  background: var(--toggle-bg);
  border: 1px solid var(--text-color);
  color: var(--text-color);
  cursor: pointer;
  font-weight: bold;
  backdrop-filter: blur(5px);
  transition: 0.3s;
}

.container {
  margin-top: 80px;
  padding: 40px;
  background: var(--container-bg);
  border-radius: 20px;
  box-shadow: var(--card-shadow);
  max-width: 500px;
  width: 90%;
}

h1 {
  font-size: 2.5rem;
  margin-bottom: 20px;
}

button.generate-btn {
  margin-top: 20px;
  padding: 15px 40px;
  font-size: 1.2rem;
  border: none;
  border-radius: 50px;
  cursor: pointer;
  background-color: var(--button-bg);
  color: var(--button-text);
  font-weight: bold;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
  transition: transform 0.2s, box-shadow 0.2s;
}

button.generate-btn:hover {
  transform: scale(1.05);
  box-shadow: 0 6px 15px rgba(0, 0, 0, 0.3);
}

.numbers {
  margin-top: 40px;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 15px;
}

.ball {
  display: inline-block;
  width: 55px;
  height: 55px;
  line-height: 55px;
  border-radius: 50%;
  font-size: 1.4rem;
  font-weight: bold;
  color: white;
  text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  animation: pop 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

@keyframes pop {
  0% { transform: scale(0); }
  100% { transform: scale(1); }
}

/* Lotto ball range colors */
.range1 { background: radial-gradient(circle at 30% 30%, #f6c23e, #d4a017); }
.range2 { background: radial-gradient(circle at 30% 30%, #36b9cc, #258391); }
.range3 { background: radial-gradient(circle at 30% 30%, #1cc88a, #13855c); }
.range4 { background: radial-gradient(circle at 30% 30%, #e74a3b, #be2617); }
.range5 { background: radial-gradient(circle at 30% 30%, #858796, #5a5c69); }