:root{--primary: #3b82f6;--primary-hover: #2563eb;--danger: #ef4444;--danger-hover: #dc2626;--bg: #ffffff;--bg-secondary: #f8fafc;--text: #0f172a;--text-secondary: #64748b;--border: #e2e8f0;--hover-bg: rgba(59, 130, 246, .04);--active-bg: rgba(59, 130, 246, .08);--focus-ring: rgba(59, 130, 246, .2);--overlay: rgba(15, 23, 42, .1);--spacing-xs: .25rem;--spacing-sm: .5rem;--spacing-md: .75rem;--spacing-lg: 1rem;--spacing-xl: 1.5rem;--spacing-2xl: 2rem;--radius-sm: 4px;--radius-md: 6px;--radius-lg: 8px;--shadow-sm: 0 1px 2px rgba(15, 23, 42, .04);--shadow-md: 0 2px 4px rgba(15, 23, 42, .06);--shadow-lg: 0 4px 6px rgba(15, 23, 42, .1);--shadow-hover: 0 4px 12px rgba(15, 23, 42, .08);--transition: .15s ease;--bounce: cubic-bezier(.34, 1.56, .64, 1);--container-width: min(90%, 800px);--header-height: 60px}[data-theme=dark]{--bg: #0f172a;--bg-secondary: #1e293b;--text: #f8fafc;--text-secondary: #94a3b8;--border: #334155;--hover-bg: rgba(59, 130, 246, .08);--active-bg: rgba(59, 130, 246, .12);--overlay: rgba(248, 250, 252, .1)}@media (min-width: 768px){:root{--spacing-xl: 2.5rem;--spacing-2xl: 4rem;--spacing-3xl: 6rem}}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{font-size:16px;height:100%}body{font-family:system-ui,-apple-system,sans-serif;line-height:1.5;background-color:var(--bg);color:var(--text);min-height:100%;transition:background-color var(--transition),color var(--transition)}button{font:inherit;border:none;background:none;cursor:pointer}input{font:inherit;border:none;outline:none}ul{list-style:none}.app-layout{display:flex;min-height:100vh;background:var(--bg)}.sidebar{width:240px;min-height:100vh;background:var(--bg-secondary);border-right:1px solid var(--border);position:fixed;left:0;top:0;padding:var(--spacing-xl) var(--spacing-md);display:flex;flex-direction:column;gap:var(--spacing-xl)}.sidebar-header h1{font-size:1.25rem;margin:0;padding:var(--spacing-md);color:var(--text)}.nav-item{width:100%;display:flex;align-items:center;gap:var(--spacing-md);padding:var(--spacing-sm) var(--spacing-md);border-radius:var(--radius-md);color:var(--text);font-size:.875rem;font-weight:500}.nav-item:hover{background:var(--hover-bg);transform:translate(2px)}.nav-item.active{background:var(--primary);color:#fff;transform:translate(4px)}.nav-item .count{margin-left:auto;min-width:20px;height:20px;padding:0 var(--spacing-xs);border-radius:10px;background:var(--bg);color:var(--text-secondary);font-size:.75rem;display:flex;align-items:center;justify-content:center;transition:all .2s var(--bounce)}.nav-item.active .count{background:#fff3;color:#fff;transform:scale(1.1)}.main-content{flex:1;margin-left:240px;min-height:100vh}.main-container{max-width:800px;margin-left:var(--spacing-2xl);min-height:100vh;display:flex;flex-direction:column}.content-header{background:var(--bg);border-bottom:1px solid var(--border);position:sticky;top:0;z-index:10;margin-bottom:var(--spacing-md)}.header-container{display:grid;grid-template-columns:minmax(0,5fr) minmax(0,1fr);gap:var(--spacing-lg);align-items:center;padding:var(--spacing-xl) 0}.input-group{display:flex;align-items:center;gap:var(--spacing-xs);width:100%}#todoInput{width:100%;height:40px;padding:0 var(--spacing-lg);font-size:.875rem;color:var(--text);background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-md);transition:all var(--transition)}#todoInput:focus{border-color:var(--primary);box-shadow:0 0 0 1px var(--primary);outline:none}#todoInput::placeholder{color:var(--text-secondary);opacity:.5}.icon-btn{width:40px;height:40px;display:flex;align-items:center;justify-content:center;background:var(--primary);color:#fff;border-radius:var(--radius-md);transition:all var(--transition);flex-shrink:0}.icon-btn:hover{background:var(--primary-hover);transform:translateY(-1px)}.icon-btn:active{transform:translateY(1px)}.icon-btn svg{width:16px;height:16px}.view-options{display:flex;justify-content:flex-end}.sort-select{height:40px;padding:0 var(--spacing-xl) 0 var(--spacing-md);font-size:.875rem;color:var(--text);background-color:var(--bg);border:1px solid var(--border);border-radius:var(--radius-md);cursor:pointer;-moz-appearance:none;appearance:none;-webkit-appearance:none;min-width:130px;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%2364748b'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right var(--spacing-sm) center;background-size:16px}.sort-select:hover{border-color:var(--primary);background-color:var(--hover-bg)}.sort-select:focus{border-color:var(--primary);box-shadow:0 0 0 1px var(--primary);outline:none;background-color:var(--bg)}@-moz-document url-prefix(){.sort-select{color:var(--text);background-color:var(--bg);border-radius:var(--radius-md)}.sort-select option{background-color:var(--bg);color:var(--text);padding:var(--spacing-md) var(--spacing-lg)}}.sort-select::-webkit-scrollbar{width:8px}.sort-select::-webkit-scrollbar-track{background:var(--bg-secondary);border-radius:var(--radius-sm)}.sort-select::-webkit-scrollbar-thumb{background:var(--border);border-radius:var(--radius-sm)}.sort-select::-webkit-scrollbar-thumb:hover{background:var(--text-secondary)}[data-theme=dark] .sort-select{background-color:var(--bg-secondary);color:var(--text);background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%2394a3b8'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E")}[data-theme=dark] .sort-select option{background-color:var(--bg);color:var(--text)}[data-theme=dark] .sidebar,[data-theme=dark] .todo-item{background:var(--bg-secondary)}[data-theme=dark] .todo-item:hover{background:var(--bg)}[data-theme=dark] #todoInput,[data-theme=dark] .sort-select{background:var(--bg-secondary)}[data-theme=dark] #todoInput:focus,[data-theme=dark] .sort-select:focus{background:var(--bg)}@media (max-width: 768px){.sidebar{width:85%;max-width:300px;transform:translate(-100%);z-index:100;background:var(--bg);box-shadow:var(--shadow-lg)}.main-content{margin-left:0;padding-top:var(--spacing-xl)}.main-container{margin-left:0;padding:0 var(--spacing-md)}.header-container{grid-template-columns:1fr;gap:var(--spacing-md);padding-top:var(--spacing-2xl)}.todo-item{padding:var(--spacing-md)}#todoInput{height:40px;font-size:16px}.sort-select{width:100%;height:40px;font-size:16px;padding:0 var(--spacing-xl) 0 var(--spacing-lg)}.todo-list{padding-top:var(--spacing-md)}}.todo-list{display:grid;gap:var(--spacing-sm);width:100%}.todo-list:empty{display:flex;align-items:center;justify-content:center;min-height:200px;background:var(--bg-secondary);border-radius:var(--radius-lg);margin:var(--spacing-xl) 0;border:2px dashed var(--border)}.todo-list:empty:after{content:"暂无待办事项";color:var(--text-secondary);font-size:1rem}.loading{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:var(--spacing-2xl);color:var(--text-secondary)}.loading-spinner{width:40px;height:40px;border:3px solid var(--border);border-top-color:var(--primary);border-radius:50%;animation:spin 1s linear infinite;margin-bottom:var(--spacing-md)}@keyframes spin{to{transform:rotate(360deg)}}.filters{display:flex;gap:var(--spacing-sm);margin:var(--spacing-xl) 0;padding:var(--spacing-sm);background:var(--bg-secondary);border-radius:var(--radius-lg)}.filters button{flex:1;padding:var(--spacing-md);color:var(--text-secondary);border-radius:var(--radius-md);transition:all var(--transition);font-weight:500}.filters button:hover{background:var(--bg);color:var(--text)}.filters button.active{background:var(--primary);color:#fff}.todo-item{display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:var(--spacing-md);padding:var(--spacing-md);background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-md);transition:transform .3s var(--bounce),opacity .3s ease}.todo-item:hover{background:var(--bg-secondary);border-color:var(--border)}.todo-item.completed{background:var(--bg);opacity:.7}.todo-item.completed .todo-text{color:var(--text-secondary);text-decoration:line-through}.todo-check{width:16px;height:16px;border:1.5px solid var(--border);border-radius:var(--radius-sm);transition:all var(--transition)}.todo-check:checked{background:var(--primary);border-color:var(--primary)}.todo-text{font-size:.875rem;line-height:1.5;color:var(--text);padding:var(--spacing-xs) 0}.delete-btn{padding:var(--spacing-xs) var(--spacing-md);color:var(--text-secondary);border-radius:var(--radius-sm);font-size:.75rem;opacity:0;transition:all var(--transition)}.todo-item:hover .delete-btn{opacity:.7}.delete-btn:hover{color:var(--danger);background:var(--hover-bg)}.content-footer{max-width:1000px;margin:0 auto;width:100%;padding:var(--spacing-md) 0;border-top:1px solid var(--border);display:flex;align-items:center;justify-content:space-between}.clear-btn{padding:var(--spacing-xs) var(--spacing-md);color:var(--text-secondary);border-radius:var(--radius-sm);font-size:.75rem;transition:all var(--transition)}.clear-btn:hover{color:var(--danger);background:var(--hover-bg)}.toast{position:fixed;bottom:var(--spacing-xl);left:50%;transform:translate(-50%);padding:var(--spacing-md) var(--spacing-xl);background:var(--danger);color:#fff;border-radius:var(--radius-md);box-shadow:var(--shadow-lg);animation:slideUp .3s ease;z-index:1000}@keyframes slideIn{0%{opacity:0;transform:translate(-20px)}to{opacity:1;transform:translate(0)}}@keyframes slideUp{0%{opacity:0;transform:translate(-50%,10px)}to{opacity:1;transform:translate(-50%)}}@media (min-width: 768px){.container{margin:var(--spacing-3xl) auto;padding:var(--spacing-2xl)}.header h1{font-size:2.5rem}.input-group{padding:var(--spacing-md)}.todo-item{padding:var(--spacing-lg)}.todo-item:hover{transform:translate(8px)}.filters{margin:var(--spacing-2xl) 0}.content-footer{padding-top:var(--spacing-xl)}}:focus-visible{outline:2px solid var(--primary);outline-offset:2px}@media (hover: hover){.todo-item{cursor:pointer}.filters button:hover{transform:translateY(-1px)}.delete-btn:hover{transform:scale(1.05)}}.todo-item.dragging{opacity:.9;background:var(--bg);box-shadow:var(--shadow-lg);transform:scale(1.02) translate(4px);cursor:grabbing}.todo-item:not(.dragging){cursor:grab}.context-menu{position:fixed;display:none;background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-md);box-shadow:var(--shadow-lg);padding:var(--spacing-xs);z-index:1000;min-width:200px}.context-menu ul{list-style:none;margin:0;padding:0}.context-menu li{padding:var(--spacing-sm) var(--spacing-md);cursor:pointer;display:flex;justify-content:space-between;align-items:center;border-radius:var(--radius-sm)}.context-menu li:hover{background:var(--bg-secondary)}.context-menu .shortcut{color:var(--text-secondary);font-size:.875rem}.edit-input{flex:1;background:var(--bg);border:2px solid var(--primary);border-radius:var(--radius-sm);padding:var(--spacing-xs) var(--spacing-sm);font-size:inherit;color:var(--text)}.todo-item:focus-within{outline:2px solid var(--primary);outline-offset:2px}.todo-check:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px var(--focus-ring)}.todo-item .delete-btn{opacity:0;transition:opacity var(--transition)}.todo-item:hover .delete-btn,.todo-item:focus-within .delete-btn{opacity:.7}@media (min-width: 769px){.sidebar{width:240px;min-height:100vh;background:var(--bg-secondary);border-right:1px solid var(--border);position:fixed;left:0;top:0;padding:var(--spacing-xl) var(--spacing-md);display:flex;flex-direction:column;gap:var(--spacing-xl)}.main-content{margin-left:240px;width:calc(100% - 240px)}.main-container,.content-header{padding:0}.header-container{padding:var(--spacing-lg) 0}.todo-list{padding-top:var(--spacing-md)}}@media (max-width: 768px){.sidebar{position:fixed;left:0;top:0;bottom:0;width:85%;max-width:320px;background:var(--bg);border-right:1px solid var(--border);z-index:100;transform:translate(-100%);transition:transform .3s var(--bounce);padding:var(--spacing-2xl) var(--spacing-lg);box-shadow:var(--shadow-lg)}.sidebar.active{transform:translate(0)}.sidebar-header{margin-bottom:var(--spacing-xl)}.sidebar-nav{margin-top:var(--spacing-xl)}.nav-item{padding:var(--spacing-md) var(--spacing-lg);margin-bottom:var(--spacing-xs)}.sidebar-overlay{display:none;position:fixed;top:0;right:0;bottom:0;left:0;background:#0000004d;z-index:99;-webkit-backdrop-filter:blur(2px);backdrop-filter:blur(2px);transition:opacity .3s ease;opacity:0}.sidebar-overlay.active{display:block;opacity:1}.main-content{padding-top:var(--spacing-2xl)}.header-container{padding-top:var(--spacing-xl)}.input-group{flex-direction:row;gap:var(--spacing-sm)}#todoInput{height:40px;font-size:16px;padding:0 var(--spacing-lg)}.icon-btn{width:40px;height:40px}.icon-btn svg{width:20px;height:20px}.sort-select{height:40px;font-size:16px;padding:0 var(--spacing-xl) 0 var(--spacing-lg)}.todo-item{padding:var(--spacing-lg);gap:var(--spacing-lg)}.todo-check{width:20px;height:20px}.todo-text{font-size:16px}.delete-btn{padding:var(--spacing-sm) var(--spacing-lg);font-size:14px;opacity:.7}}[data-theme=dark] .menu-btn{background:var(--bg-secondary);border-color:var(--border)}[data-theme=dark] .menu-btn:hover{background:var(--hover-bg);border-color:var(--primary)}[data-theme=dark] .sidebar-overlay{background:#00000080;-webkit-backdrop-filter:blur(3px);backdrop-filter:blur(3px)}@media (hover: none){.menu-btn:active{background:var(--active-bg)}.nav-item:active{transform:translate(4px)}.todo-item:active{background:var(--hover-bg)}.delete-btn{opacity:.7}}@media (min-width: 769px){.header-container{grid-template-columns:minmax(0,3fr) minmax(0,1fr);gap:var(--spacing-lg)}}@media (max-width: 768px){.header-container{grid-template-columns:1fr;gap:var(--spacing-md);padding:var(--spacing-lg) var(--spacing-lg) var(--spacing-md);margin-top:var(--spacing-xl)}.view-options{justify-content:stretch}.sort-select{width:100%}}@media (min-width: 769px){.main-container{padding:0 var(--spacing-2xl)}.todo-list{padding:var(--spacing-xl) 0}}@media (max-width: 768px){.main-container{padding:0 var(--spacing-md)}.todo-list{padding:var(--spacing-md) 0}.todo-item{padding:var(--spacing-md)}#todoInput{font-size:16px}}@media (hover: none){.delete-btn{opacity:.7;padding:var(--spacing-sm) var(--spacing-md)}.todo-item:active{background:var(--hover-bg)}.nav-item:active{background:var(--active-bg)}}@media (prefers-color-scheme: dark){.sidebar-overlay{background:#00000080}}.menu-btn{display:none;border:none;background:none;padding:var(--spacing-sm);cursor:pointer;color:var(--text)}@media (max-width: 768px){.menu-btn{display:block;position:fixed;top:var(--spacing-md);left:var(--spacing-md);z-index:1000}.sidebar{transform:translate(-100%);transition:transform var(--transition)}.sidebar.active{transform:translate(0)}}.custom-select{position:relative;width:130px}.select-button{width:100%;height:40px;padding:0 var(--spacing-lg) 0 var(--spacing-md);display:flex;align-items:center;justify-content:space-between;gap:var(--spacing-sm);font-size:.875rem;color:var(--text);background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-md);cursor:pointer;transition:all var(--transition)}.select-button:hover{border-color:var(--primary);background:var(--hover-bg)}.select-dropdown{position:absolute;top:calc(100% + 4px);left:0;width:100%;background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-md);box-shadow:var(--shadow-lg);opacity:0;visibility:hidden;transform:translateY(-8px);transition:all var(--transition);z-index:100}.custom-select.open .select-dropdown{opacity:1;visibility:visible;transform:translateY(0);pointer-events:auto}.custom-select:not(.open) .select-dropdown{pointer-events:none}.select-dropdown li{padding:var(--spacing-md) var(--spacing-lg);font-size:.875rem;color:var(--text);cursor:pointer;transition:all var(--transition)}.select-dropdown li:hover{background:var(--hover-bg)}.select-dropdown li[aria-selected=true]{color:var(--primary);background:var(--hover-bg)}[data-theme=dark] .select-button,[data-theme=dark] .select-dropdown{background:var(--bg-secondary)}@media (max-width: 768px){.custom-select{width:100%}.select-button{height:40px;font-size:16px}.select-dropdown li{padding:var(--spacing-md) var(--spacing-lg);font-size:16px}}.todo-item.sorting{opacity:.8;transform:scale(.98)}.sort-indicator{position:fixed;top:20px;right:20px;padding:var(--spacing-md) var(--spacing-lg);background:var(--primary);color:#fff;border-radius:var(--radius-md);font-size:.875rem;box-shadow:var(--shadow-lg);opacity:0;transform:translateY(-10px);transition:all .3s var(--bounce);z-index:1000}.sort-indicator.show{opacity:1;transform:translateY(0)}.empty-state{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:var(--spacing-2xl);text-align:center;color:var(--text-secondary);min-height:200px}.empty-state-icon{font-size:3rem;margin-bottom:var(--spacing-lg);opacity:.5}.empty-state-text{font-size:.875rem;line-height:1.5}.empty-state-hint{font-size:.75rem;margin-top:var(--spacing-sm);color:var(--text-secondary);opacity:.8}