:root {
  --primary-color: #4a90e2;
  --bg-gradient: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
  --container-bg: white;
  --text-main: #333;
  --text-sub: #666;
  --ball-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
  --transition-speed: 0.3s;
  --input-bg: #f1f2f6;
  --input-text: #2f3542;
}

body.dark-mode {
  --bg-gradient: linear-gradient(135deg, #1a1a1a 0%, #2d3436 100%);
  --container-bg: #2d3436;
  --text-main: #f5f5f5;
  --text-sub: #b2bec3;
  --input-bg: #3d4648;
  --input-text: #f5f5f5;
}

body {
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: var(--bg-gradient);
  background-attachment: fixed;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  transition: background var(--transition-speed), color var(--transition-speed);
}

.container {
  background: var(--container-bg);
  padding: 3rem;
  border-radius: 20px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  text-align: center;
  max-width: 600px;
  width: 90%;
  transition: background-color var(--transition-speed);
  margin: 2rem 0;
}

h1, h2 {
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

p {
  color: var(--text-sub);
  margin-bottom: 2rem;
}

.numbers-container {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 15px;
  margin-bottom: 2.5rem;
  min-height: 80px;
}

.ball {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  display: flex;
  justify-content: center;
  align-items: center;
  font-weight: bold;
  font-size: 1.5rem;
  color: white;
  box-shadow: var(--ball-shadow);
  text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
  animation: popIn 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275) both;
}

@keyframes popIn {
  from { transform: scale(0); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

.ball-range-1 { background: radial-gradient(circle at 30% 30%, #fbc531, #e1b12c); }
.ball-range-2 { background: radial-gradient(circle at 30% 30%, #487eb0, #40739e); }
.ball-range-3 { background: radial-gradient(circle at 30% 30%, #e84118, #c23616); }
.ball-range-4 { background: radial-gradient(circle at 30% 30%, #7f8fa6, #718093); }
.ball-range-5 { background: radial-gradient(circle at 30% 30%, #4cd137, #44bd32); }

.button-group {
  display: flex;
  justify-content: center;
  gap: 15px;
  flex-wrap: wrap;
}

.btn {
  border: none;
  padding: 1rem 2rem;
  font-size: 1.1rem;
  font-weight: bold;
  border-radius: 50px;
  cursor: pointer;
  transition: transform 0.2s, background-color 0.2s, box-shadow 0.2s;
}

.generate-btn {
  background-color: var(--primary-color);
  color: white;
  box-shadow: 0 4px 15px rgba(74, 144, 226, 0.3);
}

.generate-btn:hover {
  background-color: #357abd;
  transform: translateY(-2px);
}

.theme-toggle-btn {
  background-color: var(--input-bg);
  color: var(--input-text);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.theme-toggle-btn:hover {
  transform: translateY(-2px);
  filter: brightness(0.9);
}

.divider {
  border: 0;
  height: 1px;
  background: var(--text-sub);
  opacity: 0.2;
  margin: 3rem 0;
}

.inquiry-form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  text-align: left;
}

.form-group input, .form-group textarea {
  width: 100%;
  padding: 1rem;
  border-radius: 10px;
  border: none;
  background-color: var(--input-bg);
  color: var(--input-text);
  font-family: inherit;
  font-size: 1rem;
  box-sizing: border-box;
}

.submit-btn {
  background-color: #2ed573;
  color: white;
  margin-top: 1rem;
  align-self: center;
}

.submit-btn:hover {
  background-color: #26af5f;
  transform: translateY(-2px);
}

.comments-section {
  margin-top: 2rem;
  text-align: left;
}

.btn:active { transform: translateY(0); }