/* ==================== AWS Summit Paris Theme ==================== */
:root {
  --aws-orange: #FF9900;
  --aws-dark: #232F3E;
  --aws-purple: #8C4FFF;
  --aws-magenta: #E91E8C;
  --aws-teal: #00D2FF;
  --glass-bg: rgba(35, 47, 62, 0.75);
  --glass-blur: 14px;
  --glass-border: rgba(255, 153, 0, 0.25);
  --radius: 16px;
  --transition-speed: 300ms;
  --text-primary: #ffffff;
  --text-secondary: rgba(255, 255, 255, 0.85);
}
* { box-sizing: border-box; }
body {
  font-family: 'Poppins', sans-serif;
  color: var(--text-primary);
  min-height: 100vh;
  margin: 0;
  padding: 0;
  background: var(--aws-dark);
  overflow-x: hidden;
}
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background: linear-gradient(-45deg, var(--aws-dark), #1a1a3e, var(--aws-purple), var(--aws-dark));
  background-size: 400% 400%;
  animation: gradientShift 20s ease infinite;
  z-index: -2;
}
.ada-bg {
  position: fixed;
  bottom: 0;
  right: 0;
  width: 40vw;
  max-width: 420px;
  height: auto;
  z-index: -1;
  pointer-events: none;
  opacity: 1;
  /* Boost visibility slightly so Ada Lovelace reads against the dark gradient */
  filter: brightness(1.35) contrast(1.15) drop-shadow(0 0 12px rgba(255,153,0,0.25));
}
@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}
.particles { position: fixed; inset: 0; z-index: -1; pointer-events: none; overflow: hidden; }
.particles span { position: absolute; width: 4px; height: 4px; background: var(--aws-orange); border-radius: 50%; opacity: 0.3; animation: float 15s infinite; }
.particles span:nth-child(2) { left: 20%; animation-delay: 2s; animation-duration: 18s; background: var(--aws-purple); }
.particles span:nth-child(3) { left: 40%; animation-delay: 4s; animation-duration: 12s; }
.particles span:nth-child(4) { left: 60%; animation-delay: 1s; animation-duration: 20s; background: var(--aws-teal); }
.particles span:nth-child(5) { left: 80%; animation-delay: 3s; animation-duration: 16s; background: var(--aws-magenta); }
.particles span:nth-child(6) { left: 10%; animation-delay: 5s; animation-duration: 14s; }
.particles span:nth-child(7) { left: 70%; animation-delay: 6s; animation-duration: 22s; background: var(--aws-purple); }
.particles span:nth-child(8) { left: 90%; animation-delay: 0s; animation-duration: 17s; background: var(--aws-teal); }
@keyframes float {
  0% { transform: translateY(100vh) scale(0); opacity: 0; }
  10% { opacity: 0.4; }
  90% { opacity: 0.1; }
  100% { transform: translateY(-10vh) scale(1.5); opacity: 0; }
}
.glass-card { background: var(--glass-bg); backdrop-filter: blur(var(--glass-blur)); -webkit-backdrop-filter: blur(var(--glass-blur)); border: 1px solid var(--glass-border); border-radius: var(--radius); box-shadow: 0 8px 32px rgba(0,0,0,0.25), inset 0 1px 0 rgba(255,153,0,0.1); padding: 1.5rem; }
.navbar { border-radius: 0 0 var(--radius) var(--radius); padding: 0.75rem 1rem; border-bottom: 2px solid var(--aws-orange); }
.navbar-brand { font-size: 1.25rem; font-weight: 700; background: linear-gradient(135deg, var(--aws-orange), var(--aws-teal)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.nav-link { color: var(--text-secondary) !important; font-weight: 500; transition: color var(--transition-speed); min-height: 44px; display: flex; align-items: center; padding: 0.5rem 1rem !important; }
.nav-link:hover { color: var(--aws-orange) !important; }
.btn-gradient { background: linear-gradient(135deg, var(--aws-orange), var(--aws-magenta)); border: none; border-radius: var(--radius); color: #fff; font-weight: 600; padding: 0.75rem 1.5rem; min-height: 44px; min-width: 44px; transition: transform var(--transition-speed), box-shadow var(--transition-speed); cursor: pointer; font-size: 1rem; }
.btn-gradient:hover { transform: scale(1.03); box-shadow: 0 6px 24px rgba(255,153,0,0.4); color: #fff; }
.btn-gradient:active { transform: scale(0.98); }
.btn-gradient:disabled { opacity: 0.6; cursor: not-allowed; transform: none; }
.btn-secondary-glass { background: rgba(140,79,255,0.2); border: 1px solid rgba(140,79,255,0.4); border-radius: var(--radius); color: #fff; font-weight: 500; padding: 0.75rem 1.5rem; min-height: 44px; min-width: 44px; transition: background var(--transition-speed), transform var(--transition-speed); cursor: pointer; }
.btn-secondary-glass:hover { background: rgba(140,79,255,0.35); transform: scale(1.02); color: #fff; }
.answer-btn { background: rgba(255,255,255,0.07); border: 2px solid rgba(255,153,0,0.2); border-radius: var(--radius); color: #fff; padding: 0.875rem 1.25rem; min-height: 44px; width: 100%; text-align: left; font-size: 1rem; transition: all var(--transition-speed); cursor: pointer; margin-bottom: 0.75rem; }
.answer-btn:hover:not(:disabled) { background: rgba(255,153,0,0.15); transform: translateX(4px); border-color: var(--aws-orange); }
.answer-btn:disabled { cursor: not-allowed; opacity: 0.7; }
.right-answer-button { background: rgba(40,167,69,0.3) !important; border-color: #28a745 !important; }
.wrong-answer-button { background: rgba(220,53,69,0.3) !important; border-color: #dc3545 !important; }
.progress-indicators { display: flex; gap: 0.5rem; justify-content: center; margin-bottom: 1.5rem; }
.progress-dot { width: 12px; height: 12px; border-radius: 50%; background: rgba(255,255,255,0.2); transition: background var(--transition-speed), transform var(--transition-speed); }
.progress-dot.correct { background: #28a745; transform: scale(1.1); }
.progress-dot.incorrect { background: #dc3545; transform: scale(1.1); }
.progress-bar-animated { transition: width 400ms ease-in-out; background: linear-gradient(135deg, var(--aws-orange), var(--aws-purple)); border-radius: 8px; }
.fade-in-up { animation: fadeInUp 400ms ease-out; }
@keyframes fadeInUp { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }
.scale-in { animation: scaleIn 300ms ease-out; }
@keyframes scaleIn { from { opacity: 0; transform: scale(0.9); } to { opacity: 1; transform: scale(1); } }
.score-circle { width: 150px; height: 150px; border-radius: 50%; background: linear-gradient(135deg, var(--aws-orange), var(--aws-magenta)); display: flex; align-items: center; justify-content: center; margin: 0 auto 1.5rem; box-shadow: 0 8px 32px rgba(255,153,0,0.3); }
.score-circle .score-text { font-size: 2.5rem; font-weight: 700; color: #fff; }
.celebration-image { border-radius: var(--radius); max-width: 100%; box-shadow: 0 8px 32px rgba(0,0,0,0.3); border: 2px solid var(--aws-orange); }
.spinner-glow { width: 3rem; height: 3rem; border: 3px solid rgba(255,153,0,0.2); border-top-color: var(--aws-orange); border-radius: 50%; animation: spin 1s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
.leaderboard-row { display: flex; justify-content: space-between; align-items: center; padding: 0.75rem 1rem; border-bottom: 1px solid rgba(255,153,0,0.15); }
.leaderboard-row.current-player { background: rgba(255,153,0,0.15); border-radius: 8px; }
.leaderboard-rank { font-weight: 700; font-size: 1.25rem; min-width: 2rem; }
.glass-input { background: rgba(255,255,255,0.08); border: 1px solid rgba(255,153,0,0.3); border-radius: var(--radius); color: #fff; padding: 0.75rem 1rem; min-height: 44px; font-size: 1rem; width: 100%; transition: border-color var(--transition-speed); }
.glass-input::placeholder { color: rgba(255,255,255,0.4); }
.glass-input:focus { outline: none; border-color: var(--aws-orange); box-shadow: 0 0 0 3px rgba(255,153,0,0.2); }
.explanation-box { background: rgba(255,153,0,0.08); border-left: 4px solid var(--aws-orange); border-radius: 0 var(--radius) var(--radius) 0; padding: 1rem 1.25rem; margin-top: 1rem; }
.explanation-box a { color: var(--aws-teal); text-decoration: underline; }
.ada-attribution { position: fixed; bottom: 1rem; right: 1rem; font-size: 0.7rem; color: rgba(255,255,255,0.3); font-style: italic; pointer-events: none; }
@media (min-width: 576px) { .glass-card { padding: 2rem; } }
@media (min-width: 768px) { .score-circle { width: 180px; height: 180px; } .score-circle .score-text { font-size: 3rem; } }
@media (max-width: 575.98px) { .navbar-brand { font-size: 1rem; } .btn-gradient, .btn-secondary-glass, .answer-btn { font-size: 0.95rem; padding: 0.625rem 1rem; } .glass-card { padding: 1rem; border-radius: 12px; } .ada-bg { display: none; } }
:focus-visible { outline: 3px solid var(--aws-orange); outline-offset: 2px; }
.glass-card p, .glass-card span, .glass-card li { text-shadow: 0 1px 3px rgba(0,0,0,0.4); }

/* ==================== Site Footer - Krisalyd credit ==================== */
.site-footer { display: flex; justify-content: center; align-items: center; padding: 2.5rem 1rem 6rem; margin-top: 2rem; }
.krisalyd-credit { display: inline-flex; flex-direction: column; align-items: center; gap: 0.5rem; text-decoration: none; color: rgba(255,255,255,0.55); font-size: 0.8rem; transition: color 300ms ease, opacity 300ms ease; opacity: 0.75; }
.krisalyd-credit:hover { color: rgba(255,255,255,0.95); opacity: 1; }
.krisalyd-logo { width: 72px; height: 72px; object-fit: cover; border-radius: 50%; border: 2px solid rgba(0,210,255,0.6); box-shadow: 0 0 16px rgba(0,210,255,0.35); display: block; }

/* ==================== Language switcher ==================== */
.lang-switch { display: inline-flex; border: 1px solid var(--glass-border); border-radius: 99px; overflow: hidden; }
.lang-btn { background: transparent; border: none; color: var(--text-secondary); font-weight: 600; font-size: 0.8rem; padding: 0.35rem 0.7rem; min-height: 36px; cursor: pointer; transition: background 200ms, color 200ms; }
.lang-btn:hover { color: #fff; }
.lang-btn.active { background: linear-gradient(135deg, var(--aws-orange), var(--aws-magenta)); color: #fff; }
.lang-btn:focus-visible { outline: 2px solid var(--aws-teal); outline-offset: 1px; }