body { 
  background: #f5f7fa; 
  font-size: 0.85rem;
}

    .main-card {
      background: #ffffff;
      border-radius: 18px;
      box-shadow: 0 4px 16px rgba(0,0,0,0.06);
      padding: 2.5rem;
    }

    .btn-modern {
      border-radius: 10px;
      padding: 0.4rem 0.9rem; 
  font-size: 0.85rem;
      font-weight: 500;
    }
.logo {
  font-weight: 800;
  font-size: 2rem;          /* větší, výraznější */
  letter-spacing: 1px;       /* trochu víc „vzduchu“ mezi písmeny */
  text-align: center;
  margin: 30px 0 15px;
  color: #ff9900;           /* Bitcoinově-oranžová */
  background: linear-gradient(90deg, #ff9900, #ffcc33);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  text-shadow: 1px 1px 3px rgba(0,0,0,0.1); /* jemný stín */
  font-family: 'Segoe UI', Roboto, sans-serif; /* moderní čitelné písmo */
}
footer {
  font-size: 0.8rem;
  color: #6c757d;  /* decentní šedá */
}
footer a {
  color: #007bff;  /* moderní modrá */
}
footer a:hover {
  text-decoration: underline;
}
.card-modern {
      border: none;
      border-radius: 1rem;
      padding: 2rem;
      background: #ffffff;
      box-shadow: 0 4px 22px rgba(0,0,0,0.06);
    }
    textarea.form-control {
      min-height: 110px;
    }

    .payment-modal {
    background: white;
    border-radius: 1rem;
    max-width: 500px;
}

.qr-img {
    border: 6px solid #f2f2f2;
    border-radius: 6px;
}

.address-box {
    font-family: monospace;
    background: #eef6ff;
    border: 1px solid #c5deff;
}

.btn-info {
    background: #b4e0ff;
    border-color: #9bd5ff;
}

.btn-info:hover {
    background: #a1d8ff;
}