body {
    background: #000000;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    padding: 20px;
    font-family: 'Lucida Sans', sans-serif;
    box-sizing: border-box;
}

.container {
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
    max-width: 800px;
}

:root {
    --font: 'Lucida Sans', sans-serif;
    --primary-black: #000000;
    --primary-white: #ffffff;
    --accent-gray: #333333;
    --light-gray: #f0f0f0;
}

.title {
    color: var(--primary-white);
    font-family: var(--font);
    text-shadow: 2px 2px 4px rgba(0,0,0,0.5);
}

.input {
    border-radius: 5px;
    background-color: var(--primary-white);
    border: 2px solid var(--primary-black);
    outline: none;
    width: 500px;
    height: 40px;
    padding: 10px;
    text-align: center;
    font-family: var(--font);
    font-size: 16px;
    box-shadow: inset 2px 2px 4px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
}

.hint {
    font-family: var(--font);
    font-size: 15px;
    color: var(--light-gray);
    margin-bottom: 15px;
}


.btn {
  appearance: button;
  background-color: #000;
  background-image: none;
  border: 1px solid #000;
  border-radius: 4px;
  box-shadow: #fff 4px 4px 0 0,#000 4px 4px 0 1px;
  box-sizing: border-box;
  color: #fff;
  cursor: pointer;
  display: inline-block;
  font-family: ITCAvantGardeStd-Bk,Arial,sans-serif;
  font-size: 14px;
  font-weight: 400;
  line-height: 20px;
  margin: 0 5px 10px 0;
  overflow: visible;
  padding: 12px 40px;
  text-align: center;
  text-transform: none;
  touch-action: manipulation;
  user-select: none;
  -webkit-user-select: none;
  vertical-align: middle;
  white-space: nowrap;
  transition: all 0.2s ease-in-out;
}

.btn:focus {
  text-decoration: none;
}

.btn:hover {
  text-decoration: none;
}

.btn:active {
  box-shadow: rgba(0, 0, 0, .125) 0 3px 5px inset;
  outline: 0;
}

.btn:not([disabled]):active {
  box-shadow: #fff 2px 2px 0 0, #000 2px 2px 0 1px;
  transform: translate(2px, 2px);
}

@media (min-width: 768px) {
  .button-50 {
    padding: 12px 50px;
  }
}


.header {
    background-color: var(--accent-gray);
    border-radius: 10px;
    margin: 10px auto;
    padding: 15px;
    text-align: center;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
    width: fit-content;
    min-width: 300px;
}

.panel {
    display: flex;
    flex-direction: column;
    align-items: center;
    background-color: #8c8c8c;
    margin: 5px;
    padding: 20px;
    border-radius: 15px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.panel:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
}

/* Loading Spinner */
.loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin-top: 20px;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid #f3f3f3;
    border-top: 4px solid #000;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading p {
    margin-top: 10px;
    font-family: var(--font);
    color: #000;
    font-size: 14px;
}

/* QR Code Fade In */
.qr-fade-in {
    animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; transform: scale(0.8); }
    to { opacity: 1; transform: scale(1); }
}

/* Download Button */
.download-btn {
    display: inline-block;
    margin-top: 15px;
    padding: 10px 20px;
    background-color: #000;
    color: #fff;
    text-decoration: none;
    border-radius: 5px;
    font-family: ITCAvantGardeStd-Bk, Arial, sans-serif;
    font-size: 14px;
    transition: all 0.3s ease;
    box-shadow: #fff 3px 3px 0 0, #000 3px 3px 0 1px;
    animation: bounceIn 0.6s ease-out;
}

.download-btn:hover {
    background-color: #333;
    transform: translateY(-2px);
    box-shadow: #fff 4px 4px 0 0, #000 4px 4px 0 1px;
}

.download-btn:active {
    transform: translateY(1px);
    box-shadow: #fff 2px 2px 0 0, #000 2px 2px 0 1px;
}

@keyframes bounceIn {
    0% { opacity: 0; transform: scale(0.3); }
    50% { opacity: 1; transform: scale(1.05); }
    70% { transform: scale(0.9); }
    100% { opacity: 1; transform: scale(1); }
}

/* Button Hover Animation */
.btn:hover {
    transform: translateY(-2px);
    box-shadow: #fff 5px 5px 0 0, #000 5px 5px 0 1px;
}

/* Input Focus Animation */
.input:focus {
    animation: glow 0.5s ease-in-out;
}

@keyframes glow {
    0% { box-shadow: 0 0 0 0 rgba(255, 255, 255, 0.7); }
    50% { box-shadow: 0 0 0 10px rgba(255, 255, 255, 0); }
    100% { box-shadow: 0 0 0 0 rgba(255, 255, 255, 0); }
}

/* Responsive Design */
@media (max-width: 768px) {
    body {
        padding: 10px;
        height: auto;
        min-height: 100vh;
    }

    .container {
        max-width: 100%;
        padding: 0 10px;
    }

    .title {
        font-size: 18px;
        text-align: center;
    }

    .input {
        width: 100%;
        max-width: 400px;
        font-size: 14px;
        height: 35px;
        padding: 8px;
    }

    .hint {
        font-size: 14px;
        text-align: center;
    }

    .btn {
        padding: 10px 30px;
        font-size: 13px;
        width: 100%;
        max-width: 300px;
    }

    .panel {
        padding: 15px;
        margin: 10px auto;
        width: 100%;
        max-width: 450px;
    }

    .header {
        margin: 5px auto;
        padding: 10px;
        width: 100%;
        max-width: 450px;
        min-width: auto;
    }

    .spinner {
        width: 35px;
        height: 35px;
    }

    .loading p {
        font-size: 13px;
    }

    .download-btn {
        padding: 8px 16px;
        font-size: 13px;
        width: 100%;
        max-width: 250px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .title {
        font-size: 16px;
    }

    .input {
        max-width: 350px;
        font-size: 13px;
        height: 32px;
    }

    .hint {
        font-size: 13px;
    }

    .btn {
        padding: 8px 25px;
        font-size: 12px;
        max-width: 280px;
    }

    .panel {
        padding: 12px;
        max-width: 400px;
    }

    .header {
        padding: 8px;
    }

    .spinner {
        width: 30px;
        height: 30px;
    }

    .loading p {
        font-size: 12px;
    }

    .download-btn {
        padding: 6px 12px;
        font-size: 12px;
        max-width: 220px;
    }

    #qrImage {
        max-width: 200px;
        height: auto;
    }
}

@media (min-width: 1200px) {
    .input {
        width: 600px;
        height: 45px;
        font-size: 18px;
    }

    .title {
        font-size: 24px;
    }

    .btn {
        padding: 15px 50px;
        font-size: 16px;
    }

    .panel {
        padding: 30px;
        max-width: 700px;
    }

    .download-btn {
        padding: 12px 25px;
        font-size: 16px;
    }
}

/* Floating Footer */
.floating-footer {
    position: fixed;
    bottom: 20px;
    right: 20px;
    display: flex;
    gap: 10px;
    z-index: 1000;
    animation: slideUp 0.5s ease-out;
}

@keyframes slideUp {
    from { transform: translateY(100px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.social-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 50px;
    height: 50px;
    background-color: var(--primary-black);
    color: var(--primary-white);
    border-radius: 50%;
    text-decoration: none;
    box-shadow: #fff 3px 3px 0 0, #000 3px 3px 0 1px;
    transition: all 0.3s ease;
    font-family: ITCAvantGardeStd-Bk, Arial, sans-serif;
}

.social-btn:hover {
    transform: translateY(-3px) scale(1.1);
    box-shadow: #fff 4px 4px 0 0, #000 4px 4px 0 1px;
}

.social-btn:active {
    transform: translateY(-1px) scale(1.05);
    box-shadow: #fff 2px 2px 0 0, #000 2px 2px 0 1px;
}

.social-btn svg {
    width: 24px;
    height: 24px;
}

/* Mobile Footer */
@media (max-width: 768px) {
    .floating-footer {
        bottom: 15px;
        right: 15px;
        gap: 8px;
    }

    .social-btn {
        width: 45px;
        height: 45px;
        box-shadow: #fff 2px 2px 0 0, #000 2px 2px 0 1px;
    }

    .social-btn:hover {
        box-shadow: #fff 3px 3px 0 0, #000 3px 3px 0 1px;
    }

    .social-btn:active {
        box-shadow: #fff 1px 1px 0 0, #000 1px 1px 0 1px;
    }

    .social-btn svg {
        width: 20px;
        height: 20px;
    }
}

@media (max-width: 480px) {
    .floating-footer {
        bottom: 10px;
        right: 10px;
        gap: 5px;
    }

    .social-btn {
        width: 40px;
        height: 40px;
    }

    .social-btn svg {
        width: 18px;
        height: 18px;
    }
}