@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@400;500;600;700;800&family=Plus+Jakarta+Sans:ital,wght@0,400;0,500;0,600;0,700;1,400&display=swap');

:root {
  --bg-dark: #0B0F19;
  --bg-card: rgba(17, 24, 39, 0.7);
  --bg-card-hover: rgba(30, 41, 59, 0.8);
  --border-glass: rgba(255, 255, 255, 0.08);
  --border-glass-glow: rgba(99, 102, 241, 0.3);
  
  --accent-cyan: #38BDF8;
  --accent-emerald: #34D399;
  --accent-indigo: #6366F1;
  --accent-purple: #A855F7;
  
  --text-main: #F8FAFC;
  --text-muted: #94A3B8;
  --text-dim: #64748B;
  
  --font-display: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
}

body {
  font-family: var(--font-body);
  background-color: var(--bg-dark);
  color: var(--text-main);
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(99, 102, 241, 0.15) 0%, transparent 45%),
    radial-gradient(circle at 85% 85%, rgba(168, 85, 247, 0.12) 0%, transparent 45%),
    radial-gradient(circle at 50% 50%, rgba(56, 189, 248, 0.06) 0%, transparent 65%);
  background-attachment: fixed;
  min-height: 100vh;
}

h1, h2, h3, h4, .font-display {
  font-family: var(--font-display);
}

/* Glassmorphism primitives */
.glass-panel {
  background: var(--bg-card);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-glass);
  box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
}

.glass-card {
  background: rgba(15, 23, 42, 0.65);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.07);
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.glass-card:hover {
  background: rgba(30, 41, 59, 0.75);
  border-color: rgba(99, 102, 241, 0.35);
  transform: translateY(-2px);
  box-shadow: 0 12px 28px -6px rgba(99, 102, 241, 0.25);
}

/* Interactive Chips */
.word-span {
  position: relative;
  transition: all 0.15s ease;
  border-bottom: 2px dashed rgba(56, 189, 248, 0.4);
  padding: 0 3px;
  border-radius: 4px;
  color: #E2E8F0;
}

.word-span:hover {
  background: rgba(56, 189, 248, 0.18);
  color: #38BDF8;
  border-bottom-color: #38BDF8;
  text-shadow: 0 0 12px rgba(56, 189, 248, 0.5);
}

.word-chip {
  animation: popIn 0.18s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.25), rgba(6, 182, 212, 0.25));
  border: 1px solid rgba(52, 211, 153, 0.4);
  color: #6EE7B7;
  font-weight: 600;
  box-shadow: 0 0 15px rgba(16, 185, 129, 0.25);
}

.pill-button {
  background: rgba(30, 41, 59, 0.7);
  border: 1px solid rgba(255, 255, 255, 0.1);
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.pill-button:hover {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.25), rgba(168, 85, 247, 0.25));
  border-color: rgba(168, 85, 247, 0.5);
  box-shadow: 0 0 20px rgba(168, 85, 247, 0.25);
  transform: scale(1.03);
}

.pill-chip {
  animation: popIn 0.18s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  background: rgba(16, 185, 129, 0.25);
  border: 1px solid rgba(52, 211, 153, 0.4);
  color: #A7F3D0;
}

/* Animations */
@keyframes popIn {
  0% { transform: scale(0.8) translateY(4px); opacity: 0; }
  100% { transform: scale(1) translateY(0); opacity: 1; }
}

@keyframes pulseGlow {
  0%, 100% { opacity: 0.4; }
  50% { opacity: 0.8; }
}

.glow-effect {
  animation: pulseGlow 3s infinite ease-in-out;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  height: 6px;
  width: 6px;
}
::-webkit-scrollbar-track {
  background: var(--bg-dark);
}
::-webkit-scrollbar-thumb {
  background: rgba(99, 102, 241, 0.3);
  border-radius: 999px;
}
::-webkit-scrollbar-thumb:hover {
  background: rgba(99, 102, 241, 0.6);
}

/* Navigation items */
.nav-item {
  position: relative;
  transition: all 0.2s ease;
  border: 1px solid transparent;
}
.nav-item.active {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.35), rgba(168, 85, 247, 0.35));
  border-color: rgba(99, 102, 241, 0.5);
  color: #FFFFFF;
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.3);
}
.nav-item:not(.active):hover {
  background: rgba(255, 255, 255, 0.05);
  border-color: rgba(255, 255, 255, 0.1);
  color: #E2E8F0;
}

/* Exercise Box */
.ej-box {
  background: rgba(245, 158, 11, 0.08);
  border: 1px solid rgba(245, 158, 11, 0.2);
  transition: all 0.2s ease;
}
.ej-box:hover {
  border-color: rgba(245, 158, 11, 0.4);
  box-shadow: 0 4px 20px rgba(245, 158, 11, 0.15);
}