:root{--color-primary: #2563eb;--color-primary-hover: #1d4ed8;--color-primary-light: #dbeafe;--color-secondary: #64748b;--color-secondary-hover: #475569;--color-success: #22c55e;--color-success-light: #dcfce7;--color-error: #ef4444;--color-error-light: #fef2f2;--color-bg: #f8fafc;--color-surface: #ffffff;--color-text: #0f172a;--color-text-muted: #64748b;--color-text-light: #94a3b8;--color-border: #e2e8f0;--color-border-hover: #cbd5e1;--radius-sm: 6px;--radius-md: 10px;--radius-lg: 16px;--radius-full: 9999px;--shadow-sm: 0 1px 2px rgba(0, 0, 0, .05);--shadow-md: 0 4px 6px -1px rgba(0, 0, 0, .07), 0 2px 4px -2px rgba(0, 0, 0, .05);--shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, .08), 0 4px 6px -4px rgba(0, 0, 0, .04);--font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji";--font-mono: "SF Mono", "Fira Code", "Fira Mono", "Roboto Mono", Menlo, Consolas, monospace;--transition-fast: .15s ease;--transition-normal: .25s ease}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{font-size:16px;-webkit-text-size-adjust:100%}body{font-family:var(--font-sans);color:var(--color-text);background-color:var(--color-bg);line-height:1.6;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}h1,h2,h3{line-height:1.2;font-weight:700}ul{list-style:none}a{color:var(--color-primary);text-decoration:none}input,button{font-family:inherit;font-size:inherit}.hidden{display:none!important}.app-header{position:sticky;top:0;z-index:100;background-color:var(--color-surface);border-bottom:1px solid var(--color-border);padding:12px 20px;text-align:center}.app-header-logo{font-size:1.25rem;font-weight:700;color:var(--color-text);text-decoration:none}.app-header-logo:hover{color:var(--color-primary)}.screen{max-width:480px;margin:0 auto;padding:24px 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24px;text-align:center;-webkit-user-select:none;user-select:none;-webkit-tap-highlight-color:transparent}.btn:active{transform:scale(.97)}.btn:disabled{opacity:.55;cursor:not-allowed;transform:none}.btn-primary{background-color:var(--color-primary);color:#fff;box-shadow:var(--shadow-sm)}.btn-primary:hover:not(:disabled){background-color:var(--color-primary-hover);box-shadow:var(--shadow-md)}.btn-secondary{background-color:var(--color-surface);color:var(--color-text);border:1.5px solid var(--color-border)}.btn-secondary:hover:not(:disabled){border-color:var(--color-border-hover);background-color:#f1f5f9}.btn-large{width:100%;padding:14px 28px;font-size:1.125rem;border-radius:var(--radius-md)}.btn-small{min-height:36px;padding:6px 16px;font-size:.875rem;border-radius:var(--radius-sm)}.link-btn{background:none;border:none;color:var(--color-primary);cursor:pointer;font-size:.9375rem;font-weight:500;padding:4px 0;transition:color var(--transition-fast)}.link-btn:hover{color:var(--color-primary-hover);text-decoration:underline}.back-btn{font-size:1rem}.home-screen{justify-content:center;text-align:center}.home-card{width:100%}.home-title{font-size:2.5rem;letter-spacing:-.02em;color:var(--color-text);margin-bottom:8px}.home-subtitle{color:var(--color-text-muted);font-size:1.0625rem;margin-bottom:32px;line-height:1.5}.home-buttons{display:flex;flex-direction:column;gap:12px;margin-bottom:20px}.how-it-works-btn{margin-bottom:24px}.how-it-works-panel{width:100%;background-color:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius-lg);padding:24px 20px;margin-bottom:24px;text-align:left;box-shadow:var(--shadow-sm)}.how-step{display:flex;align-items:center;gap:14px;padding:10px 0;font-size:.9375rem;color:var(--color-text);line-height:1.5}.how-step+.how-step{border-top:1px solid var(--color-border)}.step-num{display:flex;align-items:center;justify-content:center;width:28px;height:28px;border-radius:var(--radius-full);background-color:var(--color-primary);color:#fff;font-weight:700;font-size:.8125rem;flex-shrink:0}.how-it-works-panel .link-btn{display:block;margin-top:16px;text-align:center;width:100%}.encryption-infographic{display:flex;align-items:center;justify-content:center;gap:4px;width:100%;padding:20px 12px;margin:16px 0;background-color:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius-lg)}.infographic-step{text-align:center;flex-shrink:0}.device-icon,.server-icon{font-size:1.5rem;margin-bottom:4px}.device-label,.server-label{font-size:.75rem;font-weight:600;color:var(--color-text)}.server-note{font-size:.625rem;color:var(--color-text-muted);font-style:italic}.infographic-arrow{display:flex;flex-direction:column;align-items:center;gap:2px;flex:1;min-width:40px}.arrow-line{width:100%;height:2px;background:repeating-linear-gradient(90deg,var(--color-primary) 0,var(--color-primary) 6px,transparent 6px,transparent 10px)}.arrow-label{font-size:.625rem;color:var(--color-primary);font-weight:600}.home-footer{color:var(--color-text-light);font-size:.8125rem;margin-top:auto;padding-top:32px;text-align:center}.tutorial-hint{font-style:italic;color:var(--color-text-muted);font-size:.9375rem;margin-bottom:20px;padding-left:14px;border-left:3px solid var(--color-primary);animation:pulse-border 2s ease-in-out 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var(--transition-normal)}.progress-text{display:block;text-align:center;color:var(--color-text-muted);font-size:.875rem;margin-bottom:16px}.code-display{width:100%;text-align:center;margin-bottom:32px}.code-digits{display:flex;justify-content:center;gap:8px;margin-bottom:16px}.code-digit{display:flex;align-items:center;justify-content:center;width:52px;height:64px;background-color:var(--color-surface);border:2px solid var(--color-border);border-radius:var(--radius-md);font-size:2rem;font-weight:700;font-family:var(--font-mono);color:var(--color-text);box-shadow:var(--shadow-sm)}.code-phrase{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;width:100%;margin-bottom:16px}.code-word{padding:10px 8px;background-color:var(--color-surface);border:2px solid var(--color-border);border-radius:var(--radius-md);font-size:1rem;font-weight:600;text-align:center;color:var(--color-text)}.phrase-input-group{display:flex;flex-direction:column;gap:8px;width:100%;margin-bottom:20px}.phrase-input{width:100%;padding:14px 16px;font-size:1rem;border:2px solid var(--color-border);border-radius:var(--radius-md);background-color:var(--color-surface);color:var(--color-text);text-align:center;font-family:var(--font-mono)}.phrase-input:focus{outline:none;border-color:var(--color-primary);box-shadow:0 0 0 3px #2563eb1a}.code-error{color:var(--color-error);font-size:.875rem;text-align:center;margin-bottom:16px;width:100%}.qr-section{width:100%;text-align:center;margin-bottom:32px}.qr-section p{color:var(--color-text-muted);font-size:.9375rem;margin-bottom:12px}.qr-container{display:flex;justify-content:center;align-items:center;margin-bottom:12px}.qr-container canvas{border-radius:var(--radius-md);box-shadow:var(--shadow-sm)}.scan-section{width:100%;text-align:center;margin-top:20px}.scanner-container{width:100%;max-width:320px;margin:16px auto 0;border-radius:var(--radius-md);overflow:hidden}.status-section{width:100%;text-align:center}.status-waiting{display:flex;flex-direction:column;align-items:center;gap:12px;margin-bottom:16px}.status-waiting p{color:var(--color-text-muted);font-size:.9375rem}.expiry-text{color:var(--color-text-light);font-size:.8125rem}.expiry-countdown{font-family:var(--font-mono);font-weight:600}.spinner{width:32px;height:32px;border:3px solid var(--color-border);border-top-color:var(--color-primary);border-radius:50%;animation:spin .8s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.send-done-screen{justify-content:center;text-align:center}.done-card{width:100%;display:flex;flex-direction:column;align-items:center;gap:16px}.done-checkmark{display:flex;align-items:center;justify-content:center;width:80px;height:80px;border-radius:50%;background-color:var(--color-success-light);color:var(--color-success);font-size:2.5rem;font-weight:700;margin-bottom:8px;box-shadow:0 0 0 8px #22c55e14}.done-card h2{font-size:1.5rem;color:var(--color-text)}.done-card p{color:var(--color-text-muted);font-size:.9375rem;max-width:300px;line-height:1.5}.done-card .btn{margin-top:8px}.loading-indicator{color:var(--color-text-muted);font-size:.9375rem;text-align:center;padding:32px 0;width:100%}.files-section{width:100%}.download-file-list{width:100%;margin-bottom:20px}.download-file-item{display:flex;align-items:center;gap:10px;padding:12px 14px;background-color:var(--color-surface);border:1px solid var(--color-border);border-radius:var(--radius-md);margin-bottom:8px}.download-file-item .file-name{flex:1;font-size:.9375rem;font-weight:500;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;min-width:0}.download-file-item .file-size{color:var(--color-text-muted);font-size:.8125rem;flex-shrink:0}.error-section{width:100%;text-align:center;padding:24px 0}.error-text{color:var(--color-error);font-size:.9375rem;margin-bottom:20px;padding:12px 16px;background-color:var(--color-error-light);border-radius:var(--radius-md)}@media(min-width:600px){.screen{max-width:520px;padding:40px 32px}.home-title{font-size:3rem}.home-subtitle{font-size:1.125rem}.home-buttons{flex-direction:row;gap:16px}.home-buttons .btn-large{flex:1}.drop-zone{padding:56px 32px}.code-digit{width:56px;height:68px;font-size:2.25rem}.how-it-works-panel{padding:28px 24px}.done-checkmark{width:96px;height:96px;font-size:3rem}}.btn:focus-visible,.link-btn:focus-visible{outline:2px solid var(--color-primary);outline-offset:2px}.phrase-input:focus-visible{border-color:var(--color-primary);box-shadow:0 0 0 3px #2563eb33}.lang-picker{display:flex;gap:8px;justify-content:center;margin-top:16px}.lang-option{background:none;border:1px solid var(--color-border);border-radius:var(--radius-sm);padding:4px 12px;font-size:.8125rem;cursor:pointer;color:var(--color-text-muted);transition:all .15s ease}.lang-option:hover{border-color:var(--color-primary);color:var(--color-primary)}.lang-option.active{border-color:var(--color-primary);color:var(--color-primary);font-weight:600}.delete-btn{color:#ef4444;margin-top:16px}.delete-btn:hover{color:#dc2626}.encryption-badge{display:inline-block;background:#dcfce7;color:#166534;padding:6px 14px;border-radius:20px;font-size:.85rem;font-weight:500;margin-top:12px}.encryption-reassurance{color:#166534;font-size:.85rem;margin-top:8px;text-align:center}