* {
  box-sizing: border-box;
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
}

body {
  margin: 0;
  background: radial-gradient(1200px 600px at top, #12122a, #07070f);
  color: #eaeaf0;
}

.back-button {
  margin: 20px;
  padding: 10px 18px;
  background: transparent;
  color: #b9b9ff;
  border: 1px solid rgba(185,185,255,0.3);
  border-radius: 10px;
  cursor: pointer;
  transition: all 0.25s ease;
}
.back-button:hover {
  background: rgba(185,185,255,0.1);
}

.crypto-container {
  max-width: 420px;
  margin: 40px auto;
  padding: 24px;
  background: rgba(255,255,255,0.04);
  border-radius: 20px;
  backdrop-filter: blur(18px);
  box-shadow: 0 20px 60px rgba(0,0,0,0.6);
}

.crypto-options > p {
  text-align: center;
  margin-bottom: 20px;
  letter-spacing: 0.4px;
}

.crypto-option {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 16px;
  margin-bottom: 12px;
  border-radius: 14px;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.08);
  cursor: pointer;
  transition: all 0.25s ease;
}

.crypto-option:hover {
  transform: translateY(-2px);
  background: rgba(255,255,255,0.08);
  border-color: rgba(120,120,255,0.5);
}

.coin-name {
  font-size: 15px;
  font-weight: 500;
}

.payment-details {
  margin-top: 20px;
  padding: 18px;
  border-radius: 16px;
  background: rgba(0,0,0,0.35);
  border: 1px solid rgba(255,255,255,0.08);
}

.highlight {
  color: #a9a8ff;
  word-break: break-all;
}

.countdown {
  font-size: 28px;
  font-weight: 300;
  text-align: center;
  margin-bottom: 16px;
  color: #a00606;
}

.confirm-button {
  width: 40%;
  margin-top: 16px;
  padding: 10px 20px;
  border-radius: 14px;
  border: none;
  background: linear-gradient(135deg, #6f6cff, #8f8cff);
  color: #fff;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.25s ease;
}

.confirm-button:hover {
  opacity: 0.9;
  transform: translateY(-1px);
}

#loading {
  text-align: center;
  font-size: 13px;
  opacity: 0.8;
}

#overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.6);
  display: none;
}

#modal {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: #ffffff;
  padding: 24px 30px;
  border-radius: 16px;
  display: none;
  box-shadow: 0 20px 50px rgba(0,0,0,0.5);
}