:root{--bg:#f4f7f7;--panel:#fff;--ink:#172128;--muted:#68747a;--accent:#1597a6;--line:#dce5e7;--shadow:0 10px 30px rgba(0,0,0,.08)}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;background:var(--bg);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Noto Sans KR",sans-serif;overscroll-behavior:none}
body{min-height:100vh;user-select:none;-webkit-user-select:none}
button,input{font:inherit}
.app{min-height:100vh;display:flex;flex-direction:column}
.topbar{position:sticky;top:0;z-index:40;background:rgba(255,255,255,.96);backdrop-filter:blur(12px);border-bottom:1px solid var(--line);display:flex;align-items:center;gap:10px;padding:10px 12px}
.brand{font-weight:800;white-space:nowrap}.spacer{flex:1}.page-indicator{font-size:14px;color:var(--muted);font-weight:700}
.icon-btn,.tool-btn{border:1px solid var(--line);background:#fff;border-radius:12px;min-width:42px;height:42px;padding:0 12px;display:inline-flex;align-items:center;justify-content:center;gap:6px;cursor:pointer}
.icon-btn:active,.tool-btn:active{transform:scale(.97)}
.tool-btn.active{background:#e8f8fa;border-color:#8ed2da;color:#087988}
.viewer-wrap{flex:1;overflow:auto;padding:18px 10px 112px;display:flex;justify-content:center;align-items:flex-start;touch-action:pan-x pan-y pinch-zoom}
.page-shell{position:relative;width:min(100%,1000px);background:#fff;border-radius:14px;box-shadow:var(--shadow);overflow:hidden}
#pageImage{display:block;width:100%;height:auto;pointer-events:none;-webkit-user-drag:none}
#inkCanvas{position:absolute;inset:0;width:100%;height:100%;touch-action:pan-x pan-y pinch-zoom;cursor:crosshair}
.watermark{position:absolute;inset:0;pointer-events:none;overflow:hidden;opacity:.14;display:grid;grid-template-columns:repeat(3,1fr);grid-auto-rows:130px;transform:rotate(-18deg) scale(1.15);transform-origin:center}
.watermark span{font-size:18px;font-weight:800;display:flex;align-items:center;justify-content:center;white-space:nowrap;color:#4f6368}
.loading{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;background:#fff;color:var(--muted);font-weight:700;z-index:4}
.toolbar{position:fixed;left:50%;bottom:14px;transform:translateX(-50%);z-index:50;background:rgba(255,255,255,.97);backdrop-filter:blur(16px);box-shadow:0 8px 30px rgba(0,0,0,.15);border:1px solid var(--line);border-radius:18px;padding:8px;display:flex;align-items:center;gap:6px;max-width:calc(100vw - 16px);overflow-x:auto;scrollbar-width:none}
.toolbar::-webkit-scrollbar{display:none}.sep{width:1px;height:30px;background:var(--line);flex:0 0 auto}.color-dot{width:22px;height:22px;border-radius:50%;border:2px solid #fff;box-shadow:0 0 0 1px #b9c4c7;flex:0 0 auto;cursor:pointer}.color-dot.active{box-shadow:0 0 0 3px #7dc8d0}.range{width:82px}.toggle{display:flex;align-items:center;gap:6px;font-size:12px;color:var(--muted);white-space:nowrap}.toggle input{accent-color:var(--accent)}
.toast{position:fixed;left:50%;top:70px;transform:translateX(-50%);background:#1f2b30;color:#fff;border-radius:999px;padding:9px 14px;font-size:13px;z-index:100;opacity:0;pointer-events:none;transition:.2s}.toast.show{opacity:1}
@media(max-width:640px){.topbar{padding:8px}.brand{font-size:14px}.icon-btn{min-width:38px;height:38px;padding:0 9px}.viewer-wrap{padding:10px 4px 105px}.page-shell{border-radius:8px}.toolbar{bottom:8px;border-radius:15px}.tool-btn{height:40px;min-width:40px;padding:0 10px}.range{width:68px}}
@media print{body{display:none!important}}