*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}:root{--bg: #f5f5f7;--card: #fff;--text: #1d1d1f;--muted: #86868b;--accent: #0071e3;--accent-hover: #0077ed;--error: #ff3b30;--success: #34c759;--warning: #ff9500;--border: #d2d2d7;--radius: 12px;--input-bg: #f5f5f7}@media(prefers-color-scheme:dark){:root{--bg: #1d1d1f;--card: #2c2c2e;--text: #f5f5f7;--muted: #98989d;--border: #48484a;--input-bg: #3a3a3c}}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background:var(--bg);color:var(--text);min-height:100vh;display:flex;align-items:center;justify-content:center;padding:16px;-webkit-font-smoothing:antialiased}#app{width:100%;max-width:440px}.header{text-align:center;margin-bottom:24px}.header h1{font-size:28px;font-weight:700;letter-spacing:-.5px}.tagline{color:var(--muted);font-size:15px;margin-top:4px}.card{background:var(--card);border-radius:var(--radius);padding:24px;box-shadow:0 1px 3px #00000014,0 4px 12px #0000000a}.file-area{margin-bottom:20px}.file-label{display:flex;align-items:center;justify-content:center;padding:20px;border:2px dashed var(--border);border-radius:8px;cursor:pointer;transition:border-color .2s;min-height:44px}.file-label:hover{border-color:var(--accent)}.file-label-text{font-size:15px;font-weight:500;color:var(--accent)}.file-input{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0)}.file-info{display:flex;justify-content:space-between;align-items:center;margin-top:10px;padding:10px 12px;background:var(--input-bg);border-radius:8px;font-size:14px}.file-name{font-weight:500;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;margin-right:8px}.file-size{color:var(--muted);white-space:nowrap}.size-warning{background:#ff95001a;color:var(--warning);border-radius:8px;padding:10px 12px;font-size:13px;margin-bottom:20px}.password-area{margin-bottom:20px}.field-label{display:block;font-size:14px;font-weight:500;margin-bottom:6px}.field-label+.field-label{margin-top:14px}.input{width:100%;padding:10px 12px;border:1px solid var(--border);border-radius:8px;font-size:16px;background:var(--input-bg);color:var(--text);outline:none;transition:border-color .2s;min-height:44px}.input:focus{border-color:var(--accent)}.input+.field-label{margin-top:14px}.seal-btn{width:100%;padding:12px;border:none;border-radius:8px;background:var(--accent);color:#fff;font-size:16px;font-weight:600;cursor:pointer;transition:background .2s,opacity .2s;min-height:44px}.seal-btn:hover:not(:disabled){background:var(--accent-hover)}.seal-btn:disabled{opacity:.5;cursor:not-allowed}.status{display:flex;align-items:center;justify-content:center;gap:8px;margin-top:16px;font-size:14px;text-align:center}.status.error{color:var(--error)}.status.success{color:var(--success)}.spinner{width:18px;height:18px;border:2px solid var(--border);border-top-color:var(--accent);border-radius:50%;animation:spin .6s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}@media(min-width:480px){.card{padding:32px}.header h1{font-size:32px}}