:root {
  --bg-color: #f8f9fa;
  --container-bg: white;
  --text-color: #333;
  --placeholder-color: #adb5bd;
  --button-bg: #007bff;
  --button-hover: #0056b3;
  --shadow-color: rgba(0,0,0,0.1);
}

[data-theme='dark'] {
  --bg-color: #1a1a1a;
  --container-bg: #2d2d2d;
  --text-color: #f8f9fa;
  --placeholder-color: #6c757d;
  --button-bg: #375a7f;
  --button-hover: #2b4764;
  --shadow-color: rgba(0,0,0,0.5);
}

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

.theme-switch-wrapper {
  position: absolute;
  top: 20px;
  right: 20px;
}

.theme-btn {
  background: var(--container-bg);
  color: var(--text-color);
  border: 1px solid var(--placeholder-color);
  padding: 8px 15px;
  border-radius: 20px;
  cursor: pointer;
  transition: all 0.3s;
  font-size: 0.9rem;
}

.container {
  text-align: center;
  background: var(--container-bg);
  padding: 30px;
  border-radius: 15px;
  box-shadow: 0 4px 15px var(--shadow-color);
  transition: background-color 0.3s, box-shadow 0.3s;
}

h1 {
  margin-bottom: 25px;
}

.numbers-container {
  display: flex;
  justify-content: center;
  gap: 12px;
  margin-bottom: 30px;
  min-height: 60px;
  align-items: center;
}

.ball {
  width: 45px;
  height: 45px;
  border-radius: 50%;
  display: flex;
  justify-content: center;
  align-items: center;
  color: white;
  font-weight: bold;
  font-size: 1.1rem;
  box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

.placeholder {
  color: var(--placeholder-color);
  font-size: 1.1rem;
}

#generate-btn {
  padding: 12px 25px;
  font-size: 1rem;
  background-color: var(--button-bg);
  color: white;
  border: none;
  border-radius: 5px;
  cursor: pointer;
  transition: background-color 0.2s;
}

#generate-btn:hover {
  background-color: var(--button-hover);
}