@keyframes spin{to{transform:rotate(360deg)}}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background:#f8fafc;min-height:100vh}.app{min-height:100vh;padding:0}.upload-container{max-width:680px;margin:30px auto;padding:0 1.5rem}.upload-card{background:#fff;border-radius:16px;padding:1.25rem 2.5rem;box-shadow:0 1px 3px #0000000a,0 4px 12px #0000000f;border:1px solid #e5e7eb}.upload-header{text-align:center;margin-bottom:1.25rem}.upload-header-icon{width:56px;height:56px;background:linear-gradient(135deg,#6366f1,#8b5cf6);border-radius:14px;display:flex;align-items:center;justify-content:center;margin:0 auto 1.25rem;color:#fff}.upload-header h1{color:#111827;font-size:1.625rem;font-weight:600;margin-bottom:.5rem;letter-spacing:-.02em}.upload-header p{color:#6b7280;font-size:.9375rem;line-height:1.5}.upload-dropzones{display:flex;flex-direction:column;gap:1.25rem;margin-bottom:1.5rem}.dropzone-container{display:flex;flex-direction:column}.dropzone-label{display:flex;align-items:center;gap:.5rem;margin-bottom:.625rem}.dropzone-label-icon{width:20px;height:20px;color:#6b7280}.dropzone-label h3{color:#374151;font-size:.875rem;font-weight:500;margin:0}.dropzone-label .optional-tag{font-size:.75rem;color:#9ca3af;font-weight:400}.dropzone{border:2px dashed #d1d5db;border-radius:12px;padding:2rem 1.5rem;text-align:center;cursor:pointer;transition:all .2s 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.dropzone-hint{color:#64748b}body.dark-mode .file-name{color:#f1f5f9}body.dark-mode .file-meta{color:#94a3b8}body.dark-mode .logo-preview{border-color:#475569}body.dark-mode .error-message{background:#450a0a;border-color:#7f1d1d;color:#fca5a5}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.spin{animation:spin 1s linear infinite}.help-dialog-overlay{position:fixed;top:0;left:0;right:0;bottom:0;background:#00000080;display:flex;align-items:center;justify-content:center;z-index:1000;padding:1rem;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px)}.help-dialog{background:#fff;border-radius:16px;width:100%;max-width:600px;max-height:85vh;display:flex;flex-direction:column;box-shadow:0 20px 50px #0003;animation:dialogSlideIn .2s ease-out}@keyframes dialogSlideIn{0%{opacity:0;transform:translateY(-20px) scale(.95)}to{opacity:1;transform:translateY(0) scale(1)}}.help-dialog-header{display:flex;justify-content:space-between;align-items:center;padding:1.25rem 1.5rem;border-bottom:1px solid #e5e7eb}.help-dialog-header h2{margin:0;font-size:1.25rem;font-weight:600;color:#111827}.help-dialog-close{width:36px;height:36px;display:flex;align-items:center;justify-content:center;border:none;background:transparent;border-radius:8px;color:#6b7280;cursor:pointer;transition:all .15s ease}.help-dialog-close:hover{background:#f3f4f6;color:#374151}.help-dialog-content{flex:1;overflow-y:auto;padding:1.5rem}.help-section{margin-bottom:1.5rem}.help-section:last-child{margin-bottom:0}.help-section h3{font-size:.9375rem;font-weight:600;color:#111827;margin:0 0 .625rem}.help-section p{font-size:.875rem;color:#4b5563;line-height:1.6;margin:0 0 .5rem}.help-section ul{margin:0;padding-left:1.25rem}.help-section li{font-size:.875rem;color:#4b5563;line-height:1.6;margin-bottom:.375rem}.help-section 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