:root{--primary:#4e89ae;--primary-hover:#2b5169;--primary-light:#a7c5d9;--background:#f1f4f8;--surface:#fff;--text:#1a1a2e;--text-secondary:#5f6368;--neutral-light:#f7f7f7;--border:1px solid #e0e0e0;--radius-lg:12px;--shadow-md:0 4px 12px #00000014;--shadow-lg:0 8px 24px #0000001f;--overlay:#0009}*{box-sizing:border-box;margin:0;padding:0;font-family:sans-serif}body{background:var(--background);color:var(--text);overflow:hidden}.help-container{width:100%;height:100vh;display:flex}.sidebar{background:var(--surface);border-right:var(--border);z-index:1000;flex-direction:column;width:280px;transition:transform .3s,width .3s;display:flex}.sidebar-header{border-bottom:1px solid var(--neutral-light);justify-content:space-between;align-items:center;height:80px;padding:0 20px;display:flex}.sidebar-header h2{color:var(--primary);font-size:18px;font-weight:800}.h1{color:var(--primary);margin-bottom:20px;font-family:Arial}.h2{font-family:Verdana}.sidebar-nav{scrollbar-width:thin;flex:1;padding:15px 10px;overflow-y:auto}.nav-item{border-radius:var(--radius-lg);width:100%;color:var(--text-secondary);cursor:pointer;text-align:left;background:0 0;border:none;align-items:center;margin-bottom:4px;padding:12px 15px;font-weight:600;transition:all .2s;display:flex}.nav-item:hover{background:var(--neutral-light);color:var(--primary)}.nav-item.active{background:var(--primary-light);color:var(--primary-hover)}.nav-index{opacity:.6;width:25px;font-size:12px}.main-area{flex-direction:column;flex:1;height:100vh;display:flex}.top-header{background:var(--surface);border-bottom:var(--border);align-items:center;gap:15px;height:80px;padding:0 20px;display:flex}.search-box{flex:1;max-width:600px;position:relative}.search-icon{opacity:.5;width:18px;height:18px;position:absolute;top:50%;left:12px;transform:translateY(-50%)}.search-input{border:var(--border);border-radius:var(--radius-lg);background:var(--neutral-light);outline:none;width:100%;padding:12px 15px 12px 40px;font-size:14px}.search-input:focus{border-color:var(--primary);background:#fff}.content-scroll{scroll-behavior:smooth;flex:1;padding:30px;overflow-y:auto}.help-card{border-radius:var(--radius-lg);border:var(--border);border-top:5px solid var(--primary);max-width:900px;box-shadow:var(--shadow-md);background:#fff;margin:0 auto;padding:30px}.section-item{border-radius:var(--radius-lg);background:var(--neutral-light);margin-bottom:15px;padding:20px}.section-item h3{color:var(--primary-hover);margin-bottom:8px}.section-item p{color:var(--text-secondary);line-height:1.6}.btn-menu-mobile{cursor:pointer;background:0 0;border:none;padding:5px;display:none}.btn-menu-mobile img{width:30px;height:30px}@media (width<=1024px){.btn-menu-mobile{display:flex}.sidebar{box-shadow:var(--shadow-lg);position:fixed;top:0;bottom:0;left:0;transform:translate(-100%)}.sidebar.mobile-open{transform:translate(0)}.sidebar-backdrop{background:var(--overlay);z-index:999;position:fixed;inset:0}}