:root{--bg: #f5f6f8;--bg-elev: #ffffff;--bg-subtle: #f1f3f5;--border: #e6e8ec;--border-strong: #d9dce2;--text: #1f2329;--text-muted: #5f6368;--text-faint: #9aa0a6;--accent: #1a73e8;--accent-700: #1765c8;--accent-soft: #e8f0fe;--success: #1e8e3e;--warn: #b06000;--error: #c5221f;--shadow-sm: 0 1px 2px rgba(60, 64, 67, .05), 0 1px 3px rgba(60, 64, 67, .06);--shadow-md: 0 1px 2px rgba(60, 64, 67, .04), 0 4px 14px rgba(60, 64, 67, .08);--shadow-lg: 0 8px 28px rgba(60, 64, 67, .12), 0 2px 6px rgba(60, 64, 67, .06);--radius-sm: 8px;--radius: 12px;--radius-lg: 16px;--radius-xl: 22px;color-scheme:light;font-family:Inter,system-ui,-apple-system,Segoe UI,sans-serif;font-feature-settings:"cv11","ss01";line-height:1.55;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}@supports (font-variation-settings: normal){:root{font-family:InterVariable,Inter,system-ui,-apple-system,Segoe UI,sans-serif}}*,*:before,*:after{box-sizing:border-box}[hidden]{display:none!important}html,body{height:100%}body{margin:0;min-height:100%;background-color:var(--bg);background-image:radial-gradient(1200px 600px at 50% -200px,#1a73e80f,#1a73e800 60%);background-repeat:no-repeat;color:var(--text)}.page{max-width:960px;margin-inline:auto;padding:2.5rem 1.5rem 3.5rem;display:flex;flex-direction:column;gap:1.75rem}main{display:flex;flex-direction:column;gap:1.25rem}.hero{text-align:center;display:flex;flex-direction:column;align-items:center;gap:.6rem}.logo{width:44px;height:44px;border-radius:13px;display:grid;place-items:center;color:#fff;background:linear-gradient(135deg,#4285f4,#1a73e8);box-shadow:var(--shadow-md)}.hero h1{margin:0;font-size:clamp(1.6rem,1.8vw + 1rem,2.1rem);font-weight:700;letter-spacing:-.02em;color:var(--text)}.subtitle{margin:0;color:var(--text-muted);font-size:.95rem}.mark-select{display:flex;gap:4px;padding:4px;background:var(--bg-subtle);border:1px solid var(--border);border-radius:999px;width:fit-content;margin-inline:auto}.mark-opt{-webkit-appearance:none;-moz-appearance:none;appearance:none;border:none;background:transparent;color:var(--text-muted);font:inherit;font-size:.88rem;font-weight:500;padding:.4rem 1rem;border-radius:999px;cursor:pointer;transition:background-color .15s,color .15s,box-shadow .15s}.mark-opt:hover{color:var(--text)}.mark-opt.is-active{background:var(--bg-elev);color:var(--accent);font-weight:600;box-shadow:var(--shadow-sm)}.mark-hint{margin:0;text-align:center;font-size:.8rem;color:var(--text-faint)}#dropzone{display:block;background:var(--bg-elev);border:1.5px dashed var(--border-strong);border-radius:var(--radius-xl);padding:3rem 1.5rem;text-align:center;cursor:pointer;box-shadow:var(--shadow-sm);transition:border-color .18s,background-color .18s,transform .18s,box-shadow .18s}#dropzone:hover,#dropzone.dragover{border-color:var(--accent);background:var(--accent-soft);box-shadow:var(--shadow-md)}.dropzone-inner{display:flex;flex-direction:column;align-items:center;gap:.5rem}.dropzone-icon{width:56px;height:56px;border-radius:16px;background:var(--accent-soft);color:var(--accent);display:grid;place-items:center;margin-bottom:.25rem}.dropzone-inner strong{font-size:1.05rem;font-weight:600;color:var(--text)}.dropzone-inner span{font-size:.9rem;color:var(--text-muted)}.dropzone-inner u{color:var(--accent);text-decoration:none;font-weight:500}.preview-card{position:relative;background:var(--bg-elev);border:1px solid var(--border);border-radius:var(--radius-xl);padding:10px;box-shadow:var(--shadow-md)}.preview-inner{position:relative;border-radius:16px;overflow:hidden;background:repeating-conic-gradient(#eaeced,#eaeced 25%,#f7f8fa 0%,#f7f8fa 50%) 50% / 18px 18px;padding:1.75rem 1.25rem;min-height:320px;display:flex;align-items:center;justify-content:center}.canvas-stack{position:relative;display:inline-block;max-width:100%;border-radius:4px;overflow:hidden;box-shadow:0 2px 12px #00000014;cursor:ew-resize;-webkit-user-select:none;user-select:none;--split: 50%;touch-action:none}canvas{display:block;max-width:100%;max-height:clamp(320px,65vh,640px);width:auto;height:auto}.canvas-overlay{position:absolute;top:0;right:0;bottom:0;left:0;width:100%;height:100%;clip-path:inset(0 calc(100% - var(--split)) 0 0)}.corner-label{position:absolute;top:12px;padding:4px 10px;font-size:.7rem;font-weight:600;letter-spacing:.04em;text-transform:uppercase;color:#fff;background:#0000008c;border-radius:999px;backdrop-filter:blur(4px);-webkit-backdrop-filter:blur(4px);pointer-events:none;z-index:3}.corner-label-left{left:12px}.corner-label-right{right:12px}.split-line{position:absolute;top:0;bottom:0;left:var(--split);width:2px;margin-left:-1px;background:#fff;box-shadow:0 0 0 1px #0000001f,0 0 14px #0000002e;pointer-events:none;z-index:4}.split-handle{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);width:36px;height:36px;border-radius:50%;background:#fff;color:#1f2329;display:grid;place-items:center;box-shadow:0 2px 6px #0000002e,0 0 0 1px #0000000f}.icon-btn{background:var(--bg-elev);border:1px solid var(--border);color:var(--text-muted);border-radius:999px;padding:0;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;transition:background-color .15s,color .15s,box-shadow .15s,transform .05s}.icon-btn:hover{background:var(--bg-subtle);color:var(--text);box-shadow:var(--shadow-sm)}.close-btn{position:absolute;top:18px;right:18px;width:36px;height:36px;z-index:5}.preview-loading{position:absolute;top:0;right:0;bottom:0;left:0;display:flex;align-items:center;justify-content:center;flex-direction:column;gap:.85rem;background:#ffffffb3;backdrop-filter:blur(4px);-webkit-backdrop-filter:blur(4px);color:var(--text-muted);font-size:.9rem;font-weight:500;z-index:1}.spinner{width:28px;height:28px;border-radius:50%;border:2.5px solid var(--border);border-top-color:var(--accent);animation:spin .85s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.actions{display:flex;flex-wrap:wrap;justify-content:center;gap:.75rem}.action-btn{-webkit-appearance:none;-moz-appearance:none;appearance:none;display:inline-flex;flex-direction:column;align-items:center;justify-content:center;gap:.4rem;min-width:130px;padding:.95rem 1.5rem;background:var(--bg-elev);border:1px solid var(--border);color:var(--text);border-radius:var(--radius);font:inherit;font-size:.88rem;font-weight:500;cursor:pointer;transition:background-color .15s,border-color .15s,color .15s,box-shadow .15s,transform .05s}.action-btn:hover:not(:disabled){background:var(--bg-subtle);border-color:var(--border-strong)}.action-btn:active:not(:disabled){transform:translateY(1px)}.action-btn:disabled{opacity:.5;cursor:not-allowed}.action-btn-primary{background:var(--accent);color:#fff;border-color:var(--accent);box-shadow:0 1px 2px #1a73e84d,0 2px 8px #1a73e82e}.action-btn-primary:hover:not(:disabled){background:var(--accent-700);border-color:var(--accent-700);box-shadow:0 1px 2px #1a73e859,0 4px 14px #1a73e840}.status-line{text-align:center;margin:0;font-size:.85rem;color:var(--text-muted)}.status-line.is-error{color:var(--error)}.status-line.is-warn{color:var(--warn)}.status-line.is-success{color:var(--success)}.toast{position:fixed;bottom:28px;left:50%;transform:translate(-50%) translateY(8px);background:#1f2329;color:#fff;font-size:.88rem;font-weight:500;padding:.6rem 1.1rem;border-radius:999px;box-shadow:var(--shadow-lg);opacity:0;transition:opacity .18s,transform .18s;z-index:10;pointer-events:none}.toast.is-visible{opacity:1;transform:translate(-50%) translateY(0)}.gwr-frame{display:block;width:100%;height:580px;border:0;background:transparent;transition:height .2s ease}.content{max-width:720px;margin:2rem auto 0;text-align:left}.content section{margin-bottom:2.5rem}.content h2{font-size:1.4rem;font-weight:700;letter-spacing:-.01em;margin:0 0 .75rem;color:var(--text)}.content h3{font-size:1.02rem;font-weight:600;margin:1.25rem 0 .35rem;color:var(--text)}.content p{margin:0 0 .85rem;color:var(--text-muted);font-size:.97rem}.content strong{color:var(--text);font-weight:600}.content ol.steps,.content ul.features{margin:0;padding-left:1.25rem;color:var(--text-muted);font-size:.97rem}.content ol.steps li,.content ul.features li{margin-bottom:.6rem}.content ul.features{list-style:none;padding-left:0}.content ul.features li{position:relative;padding-left:1.6rem}.content ul.features li:before{content:"";position:absolute;left:0;top:.45em;width:14px;height:14px;background:var(--accent);-webkit-mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'/%3E%3C/svg%3E") center / contain no-repeat;mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'/%3E%3C/svg%3E") center / contain no-repeat}body.is-embed .content{display:none}.footnote{text-align:center;font-size:.82rem;color:var(--text-faint);margin-top:.5rem}.footnote a{color:var(--text-muted);text-decoration:none;border-bottom:1px dashed var(--border-strong)}.footnote a:hover{color:var(--accent);border-bottom-color:var(--accent)}body.is-embed{background:transparent;min-height:100vh}html.is-iframed{height:auto}body.is-iframed{height:auto;min-height:0}body.is-embed .page{padding:1rem;gap:1rem;max-width:920px}body.is-embed main{gap:1rem}body.is-embed .preview-inner{padding:1.25rem 1rem;min-height:260px}body.is-embed canvas,body.is-embed .canvas-stack{max-height:640px}body.is-embed #dropzone{padding:2.25rem 1rem}@media (max-width: 540px){.page{padding:1.5rem 1rem 2.5rem;gap:1.25rem}.preview-inner{padding:1.25rem .75rem;min-height:240px}.action-btn{min-width:calc(50% - .4rem);padding:.85rem .5rem}}