:root{--bg:#ffffff;--surface:#ffffff;--surface-strong:#ffffff;--line:#e4e4e7;--line-strong:#d4d4d8;--text:#0a0a0a;--muted:#71717a;--ink:#0a0a0a;--ink-deep:#000000;--success-bg:#f4f4f5;--success-text:#0a0a0a;--error-bg:#0a0a0a;--error-text:#ffffff;--shadow:0 10px 30px rgba(0,0,0,0.08);--radius-lg:28px;--radius-md:18px;--radius-sm:14px;--max-width:480px;--font-sans:"SF Pro Display","Segoe UI","Helvetica Neue",Arial,sans-serif}*{box-sizing:border-box}html{background:var(--bg)}body{margin:0;min-height:100vh;color:var(--text);font-family:var(--font-sans)}button,input,select{font:inherit}button{cursor:pointer}a{color:inherit}.page-shell{min-height:100vh;padding:24px 16px 48px}.app-card{width:min(100%,var(--max-width));margin:0 auto;padding:20px 18px 32px;background:var(--surface-strong);border:1px solid var(--line);border-radius:34px;box-shadow:var(--shadow)}.header{margin-bottom:20px;text-align:center}.brand-logo{display:block;width:auto;max-width:220px;height:auto;margin:4px auto 12px}.header h1{margin:0;font-size:28px;line-height:1.05;letter-spacing:-.04em}.stack{display:grid;grid-gap:14px;gap:14px}.auth-button,.ghost-button,.primary-button,.secondary-button{display:inline-flex;align-items:center;justify-content:center;gap:12px;width:100%;min-height:56px;border-radius:var(--radius-md);border:0;font-size:17px;font-weight:700;transition:transform .18s ease,box-shadow .18s ease,background-color .18s ease}.auth-button,.primary-button{color:#ffffff;background:var(--ink)}.secondary-button{color:var(--text);background:#ffffff;border:1px solid var(--line-strong)}.ghost-button{color:var(--text);background:#f4f4f5}.auth-button:disabled,.ghost-button:disabled,.primary-button:disabled,.secondary-button:disabled{opacity:.4;cursor:not-allowed;box-shadow:none}.auth-button:not(:disabled):active,.ghost-button:not(:disabled):active,.primary-button:not(:disabled):active,.secondary-button:not(:disabled):active{transform:translateY(1px)}.section-card{padding:16px;background:var(--surface-strong);border:1px solid var(--line);border-radius:24px}.grid-two{display:grid;grid-template-columns:1fr 1fr;grid-gap:12px;gap:12px}.field{display:grid;grid-gap:8px;gap:8px}.field label{font-size:14px;font-weight:700}.input,.select-button{width:100%;min-height:52px;padding:14px 16px;border:1px solid var(--line-strong);border-radius:16px;background:#ffffff;color:var(--text);font-size:16px}.select-button{display:flex;align-items:center;justify-content:space-between}.auth-button:focus-visible,.ghost-button:focus-visible,.input:focus-visible,.primary-button:focus-visible,.secondary-button:focus-visible,.select-button:focus-visible{outline:3px solid rgba(0,0,0,.2);outline-offset:2px}.meta-box{display:flex;justify-content:space-between;gap:12px;padding:14px 16px;border-radius:18px;background:#ffffff;border:1px solid var(--line)}.meta-box strong{display:block;margin-bottom:4px;font-size:14px}.meta-box span{color:var(--muted);font-size:14px}.preview-card{position:relative;overflow:hidden;min-height:320px;border-radius:28px;background:#fafafa;border:1px solid var(--line)}.preview-empty{display:flex;min-height:320px;align-items:center;justify-content:center;padding:28px;text-align:center}.preview-empty strong{display:block;font-size:20px;color:var(--muted)}.preview-fab{position:absolute;left:50%;bottom:18px;transform:translateX(-50%);display:inline-flex;align-items:center;justify-content:center;width:82px;height:82px;border-radius:999px;border:8px solid #ffffff;background:var(--ink);color:#ffffff;box-shadow:0 12px 28px rgba(0,0,0,.18)}.pages-grid{display:grid;grid-template-columns:repeat(3,1fr);grid-gap:8px;gap:8px;width:100%;padding:12px}.page-thumb{position:relative;aspect-ratio:3/4;overflow:hidden;border-radius:12px;border:1px solid var(--line-strong);background:#ffffff}.page-thumb img{width:100%;height:100%;object-fit:cover}.page-index{bottom:6px;left:6px;padding:2px 8px;border-radius:999px;font-size:12px;font-weight:700}.page-index,.page-remove{position:absolute;background:var(--ink);color:#ffffff}.page-remove{top:6px;right:6px;display:flex;align-items:center;justify-content:center;width:28px;height:28px;border:0;border-radius:999px;font-size:18px;line-height:1}.preview-actions{display:grid;grid-template-columns:1fr 1fr;grid-gap:12px;gap:12px}.segmented{display:grid;grid-template-columns:1fr 1fr;padding:4px;border:1px solid var(--line-strong);border-radius:18px;background:#ffffff}.segment{min-height:48px;border:0;border-radius:14px;color:var(--muted);background:transparent;font-size:16px;font-weight:700}.segment.active{color:#ffffff;background:var(--ink)}.notice{display:flex;gap:12px;padding:14px 16px;border-radius:18px;font-size:15px;line-height:1.5}.notice.success{color:var(--success-text);background:var(--success-bg);border:1px solid var(--line-strong)}.notice.error{color:var(--error-text);background:var(--error-bg)}.folder-sheet-backdrop{position:fixed;inset:0;background:rgba(0,0,0,.4);z-index:20}.folder-sheet{position:fixed;inset:auto 0 0;z-index:21;padding:12px 12px calc(12px + env(safe-area-inset-bottom))}.folder-sheet-panel{width:min(100%,520px);margin:0 auto;padding:16px;border-radius:28px 28px 20px 20px;background:#ffffff;box-shadow:0 -20px 50px rgba(0,0,0,.18)}.sheet-handle{width:54px;height:6px;margin:0 auto 16px;background:var(--line-strong);border-radius:999px}.sheet-header{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:12px}.sheet-header h2{margin:0;font-size:24px;letter-spacing:-.03em}.breadcrumbs{margin:0 0 14px;color:var(--muted);font-size:14px}.folder-list{display:grid;grid-gap:10px;gap:10px;margin-bottom:14px}.folder-row{justify-content:space-between;width:100%;padding:15px 16px;color:var(--text);background:#ffffff;border:1px solid var(--line);border-radius:18px;text-align:left}.folder-name,.folder-row{display:flex;align-items:center;gap:12px}.folder-name{font-weight:600}.folder-form{display:grid;grid-gap:12px;gap:12px;padding:12px 0 4px}.hidden-input{display:none}.loading-text{color:var(--muted);text-align:center;padding:18px 0}@media (min-width:768px){.page-shell{padding-top:40px}.app-card{padding:28px 24px 36px}}