*{box-sizing:border-box;margin:0;padding:0}:root{--primary:#1a73e8;--primary-dark:#1557b0;--primary-light:#e8f0fe;--bg:#f5f7fa;--card:#fff;--border:#e2e8f0;--text:#1f2937;--text-light:#6b7280;--danger:#c0392b;--danger-bg:#fdecea;--radius:12px;--shadow:0 1px 3px #00000014, 0 1px 2px #0000000a}body{background:var(--bg);color:var(--text);-webkit-font-smoothing:antialiased;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,PingFang TC,Microsoft JhengHei,Noto Sans TC,sans-serif;line-height:1.6}button{cursor:pointer;border:none;border-radius:8px;font-family:inherit;transition:all .15s}input,select,textarea{border:1px solid var(--border);color:var(--text);background:#fff;border-radius:8px;outline:none;padding:8px 12px;font-family:inherit;font-size:14px;transition:border-color .15s}input:focus,select:focus,textarea:focus{border-color:var(--primary);box-shadow:0 0 0 3px #1a73e81f}.btn-primary{background:var(--primary);color:#fff;padding:9px 18px;font-size:14px;font-weight:500}.btn-primary:hover{background:var(--primary-dark)}.btn-secondary{background:var(--card);color:var(--text);border:1px solid var(--border);padding:9px 18px;font-size:14px}.btn-secondary:hover{background:#f8fafc}.btn-danger{background:var(--danger-bg);color:var(--danger);padding:6px 12px;font-size:13px}.btn-danger:hover{background:#f8d7d0}.btn-sm{padding:4px 10px;font-size:13px}.login-page{background:linear-gradient(135deg,#e8f0fe 0%,#f5f7fa 100%);justify-content:center;align-items:center;min-height:100vh;padding:20px;display:flex}.login-card{background:var(--card);border-radius:16px;width:100%;max-width:400px;padding:40px 36px;box-shadow:0 8px 30px #0000001a}.login-card h1{color:var(--text);margin-bottom:6px;font-size:22px}.login-card .subtitle{color:var(--text-light);margin-bottom:28px;font-size:14px}.login-card label{color:var(--text-light);margin-top:16px;margin-bottom:6px;font-size:13px;display:block}.login-card input{width:100%;padding:10px 12px}.login-error{background:var(--danger-bg);color:var(--danger);border-radius:8px;margin-top:16px;padding:10px 12px;font-size:13px}.login-card .btn-primary{width:100%;margin-top:24px;padding:12px;font-size:15px}.login-switch{text-align:center;color:var(--text-light);margin-top:18px;font-size:13px}.login-switch a{color:var(--primary);cursor:pointer;font-weight:500;text-decoration:none}.login-switch a:hover{text-decoration:underline}.app-layout{max-width:960px;margin:0 auto;padding:24px 20px 60px}.app-header{border-bottom:1px solid var(--border);justify-content:space-between;align-items:center;margin-bottom:24px;padding-bottom:16px;display:flex}.app-header h1{color:var(--text);font-size:20px}.app-header .user-info{color:var(--text-light);align-items:center;gap:12px;font-size:14px;display:flex}.stats-row{grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:14px;margin-bottom:24px;display:grid}.stat-card{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);text-align:center;padding:16px}.stat-card .num{color:var(--primary);font-size:26px;font-weight:700}.stat-card .label{color:var(--text-light);margin-top:2px;font-size:13px}.tasks-section{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);padding:20px}.tasks-header{justify-content:space-between;align-items:center;margin-bottom:16px;display:flex}.tasks-header h2{font-size:16px}.task-filters{flex-wrap:wrap;gap:8px;margin-bottom:16px;display:flex}.task-filters .filter-btn{background:var(--bg);color:var(--text-light);border:1px solid var(--border);padding:5px 12px;font-size:13px}.task-filters .filter-btn.active{background:var(--primary-light);color:var(--primary);border-color:var(--primary);font-weight:500}.task-list{flex-direction:column;gap:10px;display:flex}.task-card{border:1px solid var(--border);border-radius:10px;align-items:flex-start;gap:14px;padding:14px 16px;transition:box-shadow .15s;display:flex}.task-card:hover{box-shadow:0 2px 8px #00000014}.task-card.done .task-title{color:var(--text-light);text-decoration:line-through}.task-check{border:2px solid var(--border);cursor:pointer;background:#fff;border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:20px;height:20px;margin-top:3px;transition:all .15s;display:flex}.task-check.done{background:var(--primary);border-color:var(--primary);color:#fff;font-size:12px}.task-check:hover{border-color:var(--primary)}.task-body{flex:1;min-width:0}.task-title{word-break:break-word;font-size:15px;font-weight:500}.task-desc{color:var(--text-light);word-break:break-word;margin-top:2px;font-size:13px}.task-meta{flex-wrap:wrap;gap:8px;margin-top:8px;display:flex}.badge{border-radius:20px;padding:2px 8px;font-size:12px;font-weight:500;display:inline-block}.task-actions{flex-shrink:0;gap:6px;display:flex}.empty-state{text-align:center;color:var(--text-light);padding:40px 20px;font-size:14px}.modal-overlay{z-index:100;background:#0006;justify-content:center;align-items:center;padding:20px;display:flex;position:fixed;inset:0}.modal{background:var(--card);border-radius:16px;width:100%;max-width:480px;padding:28px;box-shadow:0 12px 40px #0003}.modal h3{margin-bottom:20px;font-size:18px}.modal label{color:var(--text-light);margin-top:14px;margin-bottom:6px;font-size:13px;display:block}.modal input,.modal select,.modal textarea{width:100%}.modal textarea{resize:vertical;min-height:70px}.modal-actions{justify-content:flex-end;gap:10px;margin-top:24px;display:flex}@media (width<=640px){.app-header{flex-direction:column;align-items:flex-start;gap:10px}.app-layout{padding:16px 12px 40px}.task-actions{flex-direction:column}}