:root {
  /* Dark Theme (Default) */
  --bg-color: oklch(0.15 0.05 250);
  --card-bg: oklch(0.25 0.05 250 / 0.7);
  --text-primary: oklch(0.98 0.01 250);
  --text-secondary: oklch(0.8 0.02 250);
  --accent-color: oklch(0.7 0.2 300);
  --btn-glow: oklch(0.7 0.2 300 / 0.5);
  --border-color: oklch(1 0 0 / 0.1);
  
  /* Lotto Ball Colors */
  --ball-1-10: oklch(0.75 0.15 80);  /* Yellow/Orange */
  --ball-11-20: oklch(0.65 0.18 230); /* Blue */
  --ball-21-30: oklch(0.6 0.15 20);   /* Red */
  --ball-31-40: oklch(0.5 0.05 250);  /* Grey */
  --ball-41-45: oklch(0.7 0.2 140);   /* Green */
}

[data-theme="light"] {
  --bg-color: oklch(0.95 0.02 250);
  --card-bg: oklch(1 0 0 / 0.8);
  --text-primary: oklch(0.2 0.05 250);
  --text-secondary: oklch(0.4 0.05 250);
  --accent-color: oklch(0.6 0.2 250);
  --btn-glow: oklch(0.6 0.2 250 / 0.3);
  --border-color: oklch(0 0 0 / 0.1);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Pretendard', sans-serif;
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

body {
  background-color: var(--bg-color);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow: hidden;
  position: relative;
}

.background-texture {
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle at 50% 50%, oklch(0.3 0.1 280 / 0.3) 0%, transparent 70%);
  opacity: 0.5;
  z-index: -1;
}

[data-theme="light"] .background-texture {
  background-image: radial-gradient(circle at 50% 50%, oklch(0.8 0.1 250 / 0.2) 0%, transparent 70%);
}

.background-texture::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3%3Ffilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
  opacity: 0.05;
  pointer-events: none;
}

.container {
  background: var(--card-bg);
  backdrop-filter: blur(20px);
  padding: 3rem;
  border-radius: 2rem;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.2);
  border: 1px solid var(--border-color);
  text-align: center;
  max-width: 500px;
  width: 90%;
  position: relative;
  animation: slideUp 0.8s cubic-bezier(0.2, 0.8, 0.2, 1);
}

.theme-toggle {
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  background: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  width: 40px;
  height: 40px;
  border-radius: 12px;
  cursor: pointer;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 1.25rem;
  transition: all 0.2s ease;
}

.theme-toggle:hover {
  background: var(--border-color);
  transform: rotate(15deg);
}

header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
  background: linear-gradient(to bottom right, var(--text-primary), var(--accent-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

header p {
  color: var(--text-secondary);
  font-size: 1rem;
  margin-bottom: 2.5rem;
}

.ball-container {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  margin-bottom: 3rem;
  min-height: 60px;
  align-items: center;
}

.placeholder-text {
  color: var(--text-secondary);
  font-style: italic;
  opacity: 0.6;
}

.ball {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  display: flex;
  justify-content: center;
  align-items: center;
  font-weight: 700;
  font-size: 1.25rem;
  color: white;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.2), inset 0 -4px 6px rgba(0, 0, 0, 0.2);
  transform: scale(0);
  animation: popIn 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275) forwards;
}

.ball.range-1 { background: var(--ball-1-10); }
.ball.range-2 { background: var(--ball-11-20); }
.ball.range-3 { background: var(--ball-21-30); }
.ball.range-4 { background: var(--ball-31-40); }
.ball.range-5 { background: var(--ball-41-45); }

.generate-btn {
  background: var(--accent-color);
  color: white;
  border: none;
  padding: 1rem 2.5rem;
  font-size: 1.125rem;
  font-weight: 700;
  border-radius: 1rem;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  box-shadow: 0 0 20px var(--btn-glow);
}

.generate-btn:hover {
  transform: translateY(-4px) scale(1.02);
  box-shadow: 0 15px 30px var(--btn-glow);
}

.generate-btn:active {
  transform: translateY(0) scale(0.98);
}

.generate-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.email-section {
  margin-top: 2rem;
  animation: fadeIn 0.5s ease-out;
}

.email-section.hidden {
  display: none;
}

.divider {
  border: none;
  border-top: 1px solid var(--border-color);
  margin-bottom: 1.5rem;
}

.section-title {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.lotto-form {
  display: flex;
  gap: 0.5rem;
  justify-content: center;
}

.input-field {
  background: var(--border-color);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 0.75rem 1rem;
  border-radius: 0.75rem;
  flex: 1;
  max-width: 250px;
  outline: none;
  transition: border-color 0.2s;
}

.input-field:focus {
  border-color: var(--accent-color);
}

.submit-btn {
  background: oklch(0.6 0.1 250 / 0.2);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 0.75rem 1.25rem;
  border-radius: 0.75rem;
  cursor: pointer;
  font-weight: 600;
  transition: all 0.2s;
}

.submit-btn:hover {
  background: var(--accent-color);
  color: white;
}

.form-status {
  margin-top: 1rem;
  font-size: 0.85rem;
  min-height: 1.25rem;
}

.status-success { color: oklch(0.7 0.2 140); }
.status-error { color: oklch(0.6 0.15 20); }

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

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

@media (max-width: 480px) {
  .container { padding: 3rem 1.5rem 2rem; }
  .ball { width: 40px; height: 40px; font-size: 1rem; }
  .ball-container { gap: 0.5rem; }
  .theme-toggle { top: 1rem; right: 1rem; width: 35px; height: 35px; }
}