:root {
    --bg-color: #121214;
    --card-bg: #1a1a1e;
    --accent: #6366f1;
    --text: #e4e4e7;
    --text-muted: #a1a1aa;
}
* { box-sizing: border-box; margin: 0; padding: 0; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; }
body { background-color: var(--bg-color); color: var(--text); display: flex; justify-content: center; align-content: center; min-height: 100vh; padding: 20px; }
.container { background: var(--card-bg); width: 100%; max-width: 450px; border-radius: 16px; padding: 30px; box-shadow: 0 10px 25px rgba(0,0,0,0.3); margin: auto; text-align: center; }
h1 { font-size: 24px; margin-bottom: 8px; color: #fff; }
p { color: var(--text-muted); font-size: 14px; margin-bottom: 24px; }
.grid { display: grid; grid-template-columns: 1fr; gap: 16px; }
button { background: var(--accent); color: white; border: none; padding: 14px; border-radius: 8px; font-weight: 600; font-size: 16px; cursor: pointer; transition: background 0.2s; width: 100%; }
button:hover { background: #4f46e5; }
.btn-secondary { background: #27272a; color: var(--text); }
.btn-secondary:hover { background: #3f3f46; }
input { background: #27272a; border: 2px solid #3f3f46; color: white; padding: 14px; border-radius: 8px; font-size: 18px; text-align: center; width: 100%; margin-bottom: 12px; letter-spacing: 2px; }
input:focus { border-color: var(--accent); outline: none; }
.hidden { display: none !important; }
#qrcode { display: flex; justify-content: center; margin: 20px 0; background: white; padding: 16px; border-radius: 12px; width: fit-content; margin: 20px auto; }
.code-display { font-size: 36px; font-weight: bold; letter-spacing: 4px; margin: 10px 0; color: #fff; }
.status { margin-top: 15px; font-weight: 500; color: var(--accent); }
.progress-bar { background: #27272a; border-radius: 10px; height: 8px; width: 100%; margin-top: 15px; overflow: hidden; }
.progress-fill { background: var(--accent); height: 100%; width: 0%; transition: width 0.1s; }
#fileInput { display: none; }