* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: 'Inter', sans-serif; background: #0a0a0a; color: #ffffff; overflow-x: hidden; }

/* Fix LaTeX display on Dark Mode */
.mjx-chtml { color: #ffffff !important; font-size: 115% !important; font-weight: bold; }

/* Sakura Petals */
@keyframes fall1 {
  0% { transform: translate(0, -10%) rotate(0deg); opacity: 0; }
  10% { opacity: 0.8; }
  90% { opacity: 0.6; }
  100% { transform: translate(80px, 110vh) rotate(360deg); opacity: 0; }
}
@keyframes fall2 {
  0% { transform: translate(0, -10%) rotate(0deg); opacity: 0; }
  10% { opacity: 0.7; }
  90% { opacity: 0.5; }
  100% { transform: translate(-60px, 110vh) rotate(-300deg); opacity: 0; }
}
@keyframes fall3 {
  0% { transform: translate(0, -10%) rotate(0deg); opacity: 0; }
  10% { opacity: 0.9; }
  90% { opacity: 0.4; }
  100% { transform: translate(100px, 110vh) rotate(420deg); opacity: 0; }
}
@keyframes fall4 {
  0% { transform: translate(0, -10%) rotate(0deg); opacity: 0; }
  10% { opacity: 0.6; }
  90% { opacity: 0.5; }
  100% { transform: translate(-90px, 110vh) rotate(-380deg); opacity: 0; }
}
@keyframes fall5 {
  0% { transform: translate(0, -10%) rotate(0deg); opacity: 0; }
  10% { opacity: 0.8; }
  90% { opacity: 0.3; }
  100% { transform: translate(50px, 110vh) rotate(280deg); opacity: 0; }
}
@keyframes fall6 {
  0% { transform: translate(0, -10%) rotate(0deg); opacity: 0; }
  10% { opacity: 0.7; }
  90% { opacity: 0.5; }
  100% { transform: translate(-40px, 110vh) rotate(-450deg); opacity: 0; }
}

@keyframes floatSlow {
  0%, 100% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(3deg); }
}
@keyframes floatMedium {
  0%, 100% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-15px) rotate(-2deg); }
}
@keyframes floatFast {
  0%, 100% { transform: translateY(0px); }
  50% { transform: translateY(-10px); }
}
@keyframes pulseGlow {
  0%, 100% { box-shadow: 0 0 20px rgba(244,114,182,0.3); }
  50% { box-shadow: 0 0 40px rgba(244,114,182,0.6); }
}
@keyframes progressFill {
  from { width: 0%; }
  to { width: 65%; }
}

.sakura-petal {
  position: absolute;
  width: 12px;
  height: 12px;
  background: radial-gradient(ellipse at center, #F9A8D4 0%, #F472B6 50%, transparent 70%);
  border-radius: 50% 0 50% 0;
  pointer-events: none;
  z-index: 10;
}

.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.active {
  opacity: 1;
  transform: translateY(0);
}

.card-hover {
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}
.card-hover:hover {
  transform: translateY(-8px) scale(1.02);
}

.hero-bg {
  background:
    linear-gradient(135deg, rgba(10,10,10,0.3) 0%, rgba(10,10,10,0.7) 40%, rgba(10,10,10,0.85) 70%, #0a0a0a 100%),
    url('https://picsum.photos/seed/mtfuji-sakura/1920/1080.jpg');
  background-size: cover;
  background-position: center 30%;
}

.glass-card {
  background: rgba(255,255,255,0.04);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255,255,255,0.08);
}

.progress-bar-fill {
  animation: progressFill 2s ease-out forwards;
  animation-play-state: paused;
}
.progress-bar-fill.animate {
  animation-play-state: running;
}

.category-card {
  transition: all 0.3s ease;
  cursor: pointer;
}
.category-card:hover {
  background: rgba(255,255,255,0.08);
  border-color: rgba(244,114,182,0.4);
}
.category-card:hover .cat-icon {
  transform: scale(1.15);
  background: rgba(244,114,182,0.15);
}
.category-card:hover .cat-arrow {
  transform: translateX(4px);
  opacity: 1;
}

.torii-gate {
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  opacity: 0.04;
  font-size: 300px;
  line-height: 1;
  pointer-events: none;
  user-select: none;
}

.btn-primary {
  background: linear-gradient(135deg, #F74E09, #D93D00);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}
.btn-primary::before {
  content: '';
  position: absolute;
  top: 0; left: -100%; width: 100%; height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
  transition: left 0.5s;
}
.btn-primary:hover::before { left: 100%; }
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 30px rgba(247,78,9,0.4);
}

.btn-secondary {
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.15);
  backdrop-filter: blur(10px);
  transition: all 0.3s ease;
}
.btn-secondary:hover {
  background: rgba(255,255,255,0.12);
  border-color: rgba(244,114,182,0.5);
  transform: translateY(-2px);
}

.feature-icon-wrap {
  transition: all 0.4s ease;
}
.card-hover:hover .feature-icon-wrap {
  transform: rotateY(180deg);
}

/* Scrollbar */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: #0a0a0a; }
::-webkit-scrollbar-thumb { background: #2e2e2e; border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #F74E09; }

.toast {
  transform: translateX(120%);
  transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}
.toast.show {
  transform: translateX(0);
}

.level-modal-overlay {
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}
.level-modal-overlay.active {
  opacity: 1;
  pointer-events: all;
}
.level-modal-overlay .modal-box {
  transform: scale(0.9) translateY(20px);
  transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}
.level-modal-overlay.active .modal-box {
  transform: scale(1) translateY(0);
}