:root {
  --neon-lime: #a6ff00;
  --neon-blue: #00f0ff;
  --bg-gradient: linear-gradient(135deg, #f6fff8 0%, #eafbff 100%);
  --card-bg: rgba(255, 255, 255, 0.85);
  --text-color: #2c3e50;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
}

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

/* 로딩 스크린 */
#loading-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: #ffffff;
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 9999;
  transition: opacity 0.5s ease, visibility 0.5s ease;
}

.loading-content {
  text-align: center;
  width: 80%;
  max-width: 300px;
}

.logo-text {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 20px;
  color: #333;
  letter-spacing: -0.5px;
}

.progress-bar-container {
  width: 100%;
  height: 6px;
  background-color: #e0e0e0;
  border-radius: 3px;
  overflow: hidden;
}

.progress-bar {
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--neon-lime), var(--neon-blue));
  animation: loadProgress 1.5s forwards ease-in-out;
}

@keyframes loadProgress {
  0% { width: 0%; }
  100% { width: 100%; }
}

/* 앱 컨테이너 메인 레이아웃 */
#app {
  width: 100%;
  max-width: 480px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  background: rgba(255, 255, 255, 0.4);
  box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.07);
  backdrop-filter: blur(4px);
  position: relative;
}

.app-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 24px 20px;
}

.app-header h1 {
  font-size: 1.5rem;
  font-weight: 800;
  background: linear-gradient(45deg, #00c6ff, #0072ff);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.bgm-btn {
  background: #ffffff;
  border: 1px solid #e0e0e0;
  border-radius: 50%;
  width: 40px;
  height: 40px;
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
  color: #555;
  transition: transform 0.2s ease;
}

.bgm-btn.playing {
  color: #00c3ff;
  animation: spin 3s linear infinite;
}

@keyframes spin {
  100% { transform: rotate(360deg); }
}

/* 2x2 메뉴 그리드 */
.main-content {
  padding: 20px;
  flex-grow: 1;
  display: flex;
  align-items: center;
}

.menu-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  width: 100%;
}

.menu-card {
  background: var(--card-bg);
  border-radius: 20px;
  aspect-ratio: 1 / 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  cursor: pointer;
  border: 2px solid transparent;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.03);
  transition: all 0.3s ease;
}

.menu-card .icon {
  font-size: 2rem;
  margin-bottom: 12px;
  color: #4a4a4a;
}

.menu-card span {
  font-weight: 600;
  font-size: 0.95rem;
}

/* 마우스 오버 네온 효과 (형광 연두/파랑) */
.menu-card:hover {
  transform: translateY(-4px);
  border-color: var(--neon-blue);
  box-shadow: 0 0 12px var(--neon-blue),
              inset 0 0 8px var(--neon-lime);
}

/* 푸터 레이아웃 */
.app-footer {
  padding: 20px;
  background: rgba(255, 255, 255, 0.6);
  border-top: 1px solid rgba(0, 0, 0, 0.05);
  font-size: 0.8rem;
  color: #666;
  line-height: 1.6;
}

.footer-info a {
  color: #333;
  text-decoration: none;
  font-weight: 600;
}

.footer-info i {
  margin-right: 6px;
  color: #888;
}

.address {
  margin-top: 4px;
  font-size: 0.75rem;
  color: #888;
}