:root{--primary-color: #5C4033;--hover-color: #3E2723;--background: #E8F5E9;--surface: #FDF8F5;--text-main: #2D1A11;--text-muted: #795548;--border: #D7CCC8;--success: #388E3C;--success-bg: #E8F5E9;--danger: #D84315;--danger-bg: #FBE9E7;--shadow-sm: 0 1px 3px rgba(92, 64, 51, .1), 0 1px 2px rgba(92, 64, 51, .2);--shadow-md: 0 4px 6px rgba(92, 64, 51, .1);--shadow-lg: 0 10px 20px rgba(92, 64, 51, .15);--radius-sm: 8px;--radius-md: 16px;--radius-lg: 24px;--radius-full: 999px}*{box-sizing:border-box;margin:0;padding:0}body{font-family:Inter,sans-serif;background-color:var(--background);color:var(--text-main);line-height:1.5;overflow-x:hidden}.view{display:none;animation:fadeIn .3s ease-out}.view.active{display:block}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}.navbar{position:sticky;top:0;z-index:100;background:#ffffffe6;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);display:flex;align-items:center;padding:12px 24px;gap:32px;box-shadow:var(--shadow-sm)}.logo{font-weight:700;font-size:1.25rem;color:var(--primary-color);flex-shrink:0}.search-bar{flex-grow:1;max-width:800px}.search-bar input{width:100%;padding:12px 20px;border-radius:var(--radius-full);border:none;background:#efefef;font-size:1rem;font-family:inherit;transition:all .2s}.search-bar input:focus{outline:none;background:var(--surface);box-shadow:0 0 0 2px #5c403333}.nav-links{display:flex;align-items:center;gap:16px}.btn-create,.btn-primary{background:var(--primary-color);color:#fff;border:none;padding:12px 24px;border-radius:var(--radius-full);font-weight:600;font-size:1rem;cursor:pointer;transition:background .2s,transform .1s}.btn-create:hover,.btn-primary:hover{background:var(--hover-color)}.btn-create:active,.btn-primary:active{transform:scale(.95)}.btn-primary:disabled{opacity:.6;cursor:not-allowed}.create-menu{display:flex;gap:8px;background:#efefef;padding:4px;border-radius:var(--radius-full)}.create-menu .btn-create{padding:8px 16px;font-size:.9rem;box-shadow:none}.btn-secondary{background:#efefef;color:var(--text-main);border:none;padding:12px 24px;border-radius:var(--radius-full);font-weight:600;font-size:1rem;cursor:pointer;transition:background .2s}.btn-secondary:hover{background:#e1e1e1}.btn-back{background:none;border:none;font-size:1rem;font-weight:600;color:var(--text-muted);cursor:pointer;display:flex;align-items:center;padding:8px;border-radius:var(--radius-sm);transition:background .2s}.btn-back:hover{background:#efefef;color:var(--text-main)}.modal-overlay{display:none;position:fixed;top:0;left:0;right:0;bottom:0;background:#2d1a1199;-webkit-backdrop-filter:blur(4px);backdrop-filter:blur(4px);z-index:1000;justify-content:center;align-items:center;animation:fadeIn .2s ease-out}.modal-overlay.active{display:flex}.modal-content{background:var(--surface);width:100%;max-width:400px;border-radius:var(--radius-lg);padding:32px;position:relative;box-shadow:var(--shadow-lg);transform:translateY(20px);animation:slideUp .3s ease-out forwards}@keyframes slideUp{to{transform:translateY(0)}}.btn-close{position:absolute;top:16px;right:16px;background:none;border:none;font-size:1.2rem;color:var(--text-muted);cursor:pointer;padding:8px;border-radius:50%;transition:background .2s}.btn-close:hover{background:#efefef;color:var(--text-main)}.auth-link{color:var(--primary-color);text-decoration:none;font-size:.9rem;font-weight:600}.auth-link:hover{text-decoration:underline}.auth-form{display:none;animation:fadeIn .3s ease-out}.auth-form.active{display:block}.auth-form h2{margin-bottom:24px;font-size:1.5rem;color:var(--text-main)}.form-group{margin-bottom:16px}.form-group label{display:block;font-weight:600;margin-bottom:8px;font-size:.9rem;color:var(--text-main)}.form-group input{width:100%;padding:12px 16px;border:1px solid var(--border);border-radius:var(--radius-sm);font-family:inherit;font-size:1rem;transition:border-color .2s}.form-group input:focus{outline:none;border-color:var(--primary-color)}.toast{position:fixed;top:80px;left:50%;transform:translate(-50%) translateY(-20px);background:var(--primary-color);color:#fff;padding:12px 28px;border-radius:var(--radius-full);font-weight:600;font-size:.95rem;box-shadow:var(--shadow-lg);z-index:9999;opacity:0;transition:opacity .3s,transform .3s;pointer-events:none}.toast.show{opacity:1;transform:translate(-50%) translateY(0)}@media (max-width: 768px){.navbar{flex-wrap:wrap;padding:10px 12px;gap:8px}.logo{font-size:1.1rem}.search-bar{order:3;flex-basis:100%;max-width:unset}.search-bar input{padding:10px 16px;font-size:.9rem}.nav-links{gap:6px;margin-left:auto}.create-menu{gap:4px;padding:2px}.create-menu .btn-create{padding:6px 10px;font-size:.75rem}.btn-secondary{padding:8px 12px;font-size:.8rem}.btn-primary{padding:8px 16px;font-size:.85rem}.modal-content{margin:16px;padding:24px;max-width:calc(100% - 32px)}}#feed-view{padding:24px;max-width:1600px;margin:0 auto}.masonry-grid{column-count:1;column-gap:24px;padding:20px 0}@media (min-width: 600px){.masonry-grid{column-count:2}}@media (min-width: 900px){.masonry-grid{column-count:3}}@media (min-width: 1200px){.masonry-grid{column-count:4}}@media (min-width: 1500px){.masonry-grid{column-count:5}}.worksheet-card{background:var(--surface);border-radius:var(--radius-md);overflow:hidden;break-inside:avoid;margin-bottom:24px;box-shadow:var(--shadow-sm);transition:transform .2s,box-shadow .2s;cursor:pointer;position:relative;display:inline-block;width:100%}.worksheet-card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg)}.card-image-wrapper{position:relative;width:100%;min-height:200px;background:#f0f0f0;overflow:hidden}.card-info{padding:12px 16px 16px}.card-title{font-size:1rem;font-weight:600;margin-bottom:4px;color:var(--text-main);display:-webkit-box;-webkit-line-clamp:2;line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.card-meta{display:flex;justify-content:space-between;align-items:center;margin-top:8px}.card-author{display:flex;align-items:center;gap:8px;font-size:.875rem;color:var(--text-muted)}.author-avatar{width:24px;height:24px;border-radius:50%;background:#ccc;object-fit:cover}@media (max-width: 768px){#feed-view{padding:12px}.masonry-grid{column-gap:12px}.worksheet-card{margin-bottom:12px}.card-title{font-size:.9rem}.card-author{font-size:.8rem}}#editor-view{height:calc(100vh - 65px);display:none;flex-direction:column;background:#e5e5e5;overflow:hidden}#editor-view.active{display:flex}.editor-header{background:#fff;padding:12px 24px;display:flex;justify-content:space-between;align-items:center;border-bottom:1px solid var(--border);flex-shrink:0;box-shadow:0 1px 2px #0000000d}.document-title-input{font-size:1.25rem;font-weight:700;font-family:inherit;border:1px solid transparent;border-radius:var(--radius-sm);padding:8px 16px;text-align:center;color:var(--text-main);transition:all .2s;background:transparent;width:300px}.document-title-input:hover{border-color:#e1e1e1}.document-title-input:focus{outline:none;border-color:var(--primary-color);background:#fff}.editor-actions{display:flex;gap:12px;align-items:center}.toggle-switch{position:relative;display:inline-block;width:44px;height:24px}.toggle-switch input{opacity:0;width:0;height:0}.toggle-slider{position:absolute;cursor:pointer;top:0;left:0;right:0;bottom:0;background-color:#ccc;transition:.3s;border-radius:24px}.toggle-slider:before{position:absolute;content:"";height:18px;width:18px;left:3px;bottom:3px;background-color:#fff;transition:.3s;border-radius:50%;box-shadow:0 2px 4px #0003}.toggle-switch input:checked+.toggle-slider{background-color:var(--primary-color)}.toggle-switch input:checked+.toggle-slider:before{transform:translate(20px)}.editor-workspace{display:flex;flex-grow:1;overflow:hidden}.document-container{flex-grow:1;overflow-y:auto;padding:40px;display:flex;justify-content:center;align-items:flex-start;scrollbar-width:thin}.document-paper{background:#fff;width:100%;max-width:800px;min-height:1056px;padding:64px;box-shadow:var(--shadow-md);border-radius:4px;font-family:Times New Roman,Times,serif;font-size:1.1rem;line-height:1.6;color:#333}.document-paper:focus{outline:none}.document-paper h1{font-family:Inter,sans-serif;font-size:2.5rem;margin-bottom:24px;color:#111}.document-paper h2{font-family:Inter,sans-serif;font-size:1.8rem;margin-top:32px;margin-bottom:16px;color:#111}.document-paper p{margin-bottom:16px}.ai-addition{background-color:var(--success-bg);border-bottom:2px solid var(--success);color:#0b7a42;position:relative;cursor:pointer}.ai-removal{background-color:var(--danger-bg);text-decoration:line-through;color:var(--danger);position:relative;cursor:pointer}.ai-sidebar{width:350px;background:#fff;border-left:1px solid var(--border);display:flex;flex-direction:column;flex-shrink:0;box-shadow:-4px 0 15px #00000008;z-index:10}.ai-header{padding:16px 24px;border-bottom:1px solid var(--border);display:flex;align-items:center;gap:12px}.ai-header-avatar{width:40px;height:40px;border-radius:50%;object-fit:cover}.chat-avatar-container{position:relative;width:36px;height:36px;flex-shrink:0;margin-top:2px}.ai-title{font-weight:600;color:var(--text-main)}.chat-history{flex-grow:1;overflow-y:auto;padding:24px;display:flex;flex-direction:column;gap:16px}.chat-message{max-width:85%;padding:12px 16px;border-radius:var(--radius-md);font-size:.95rem;line-height:1.4;animation:fadeIn .3s ease-out}.chat-message-row{display:flex;align-items:flex-start;gap:8px}.chat-message-row.ai{align-self:flex-start;max-width:90%}.chat-avatar{width:36px;height:36px;border-radius:50%;object-fit:cover;flex-shrink:0;margin-top:2px}.chat-message.ai{background:#f4f6f8;color:var(--text-main);align-self:flex-start;border-bottom-left-radius:4px}.chat-message.user{background:var(--primary-color);color:#fff;align-self:flex-end;border-bottom-right-radius:4px}.chat-input-area{padding:16px;border-top:1px solid var(--border);display:flex;gap:8px;background:#fff;position:relative;z-index:2}.sammy-popup{position:absolute;bottom:100%;left:24px;margin-bottom:-15px;z-index:3;animation:popupAnimation .5s cubic-bezier(.175,.885,.32,1.275) forwards}.sammy-popup img{width:60px;height:60px;border-radius:50%;object-fit:cover;background:#fff;box-shadow:0 4px 10px #00000026;border:3px solid white}@keyframes popupAnimation{0%{transform:translateY(20px) scale(.8);opacity:0}to{transform:translateY(0) scale(1);opacity:1}}.chat-input-area input{flex-grow:1;padding:12px 16px;border:1px solid var(--border);border-radius:var(--radius-full);outline:none;font-family:inherit;font-size:.95rem;transition:border-color .2s}.chat-input-area input:focus{border-color:var(--primary-color)}#send-btn{background:var(--primary-color);color:#fff;border:none;width:44px;height:44px;border-radius:50%;cursor:pointer;display:flex;justify-content:center;align-items:center;transition:background .2s,transform .1s}#send-btn:hover{background:var(--hover-color)}#send-btn:active{transform:scale(.9)}.typing-indicator{display:flex;align-items:center;gap:4px;padding:12px 16px}.typing-indicator .dot{width:8px;height:8px;border-radius:50%;background:var(--text-muted);animation:typingBounce 1.4s infinite ease-in-out}.typing-indicator .dot:nth-child(1){animation-delay:0s}.typing-indicator .dot:nth-child(2){animation-delay:.2s}.typing-indicator .dot:nth-child(3){animation-delay:.4s}@keyframes typingBounce{0%,80%,to{transform:scale(.6);opacity:.4}40%{transform:scale(1);opacity:1}}#diff-review-bar{position:absolute;bottom:0;left:0;right:350px;background:#fff;border-top:2px solid var(--primary-color);padding:12px 24px;display:flex;justify-content:space-between;align-items:center;box-shadow:0 -4px 12px #0000001a;z-index:50;transform:translateY(100%);transition:transform .3s cubic-bezier(.4,0,.2,1)}#diff-review-bar.active{transform:translateY(0)}.diff-review-summary{display:flex;align-items:center;gap:10px;font-size:.95rem}.diff-icon{font-size:1.2rem}.diff-label{font-weight:600;color:var(--text-main)}.diff-stat{padding:3px 10px;border-radius:var(--radius-full);font-size:.85rem;font-weight:600}.diff-stat-add{background:var(--success-bg);color:var(--success)}.diff-stat-remove{background:var(--danger-bg);color:var(--danger)}.diff-review-actions{display:flex;gap:10px}.diff-btn{padding:8px 20px;border-radius:var(--radius-full);font-weight:600;font-size:.9rem;cursor:pointer;border:2px solid transparent;transition:all .2s}.diff-btn-accept{background:var(--success);color:#fff;border-color:var(--success)}.diff-btn-accept:hover{background:#2e7d32;border-color:#2e7d32}.diff-btn-reject{background:#fff;color:var(--danger);border-color:var(--danger)}.diff-btn-reject:hover{background:var(--danger-bg)}@media (max-width: 768px){#editor-view{height:auto;min-height:calc(100vh - 65px);overflow:auto}.editor-header{flex-wrap:wrap;padding:8px 12px;gap:8px}.btn-back{font-size:.85rem;padding:6px}.document-title-input{width:100%;order:3;font-size:1rem;padding:6px 10px;text-align:left}.editor-actions{gap:6px;margin-left:auto}.editor-actions .btn-secondary,.editor-actions .btn-primary{padding:8px 12px;font-size:.8rem}.editor-workspace{flex-direction:column;overflow:auto}.document-container{padding:12px}.document-paper{padding:24px;min-height:400px;font-size:1rem}.document-paper h1{font-size:1.6rem;margin-bottom:16px}.document-paper h2{font-size:1.3rem;margin-top:20px;margin-bottom:10px}.ai-sidebar{width:100%;border-left:none;border-top:1px solid var(--border);max-height:350px}.chat-history{padding:12px;gap:10px}.chat-message{font-size:.85rem;padding:10px 12px}.chat-input-area{padding:10px}.sammy-popup{left:12px}.sammy-popup img{width:40px;height:40px}#diff-review-bar{right:0;flex-direction:column;gap:8px;padding:10px 16px}}