:root{--primary: #2563eb;--bg-sidebar: rgba(255, 255, 255, .8);--bg-card: #ffffff;--text-main: #1f2937;--text-muted: #6b7280;--border: #e5e7eb;--shadow: 0 1px 3px rgba(0,0,0,.1);--success: #10b981;--danger: #ef4444}.dark-mode{--primary: #60a5fa;--bg-sidebar: rgba(15, 23, 42, .8);--bg-card: #1e293b;--text-main: #f8fafc;--text-muted: #94a3b8;--border: #334155;--shadow: 0 4px 6px -1px rgba(0, 0, 0, .5)}html,body{height:100%;margin:0;padding:0;width:100%;overflow-x:hidden}body{font-family:Inter,system-ui,sans-serif;color:var(--text-main);transition:color .3s;background:linear-gradient(-45deg,#eff6ff,#dbeafe,#e0e7ff,#f3e8ff);background-size:400% 400%;animation:gradientBG 15s ease infinite}body.dark-mode{background:linear-gradient(-45deg,#0f172a,#1e1b4b,#312e81,#020617)!important;background-size:400% 400%;animation:gradientBG 15s ease infinite}@keyframes gradientBG{0%{background-position:0% 50%}50%{background-position:100% 50%}to{background-position:0% 50%}}.dashboard-container{display:flex;min-height:100vh}.sidebar{width:250px;background:var(--bg-sidebar);-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border-right:1px solid var(--border);padding:20px;transition:all .3s ease}.main-content{flex:1;padding:30px}.card{background:var(--bg-card);padding:20px;border-radius:12px;box-shadow:var(--shadow);margin-bottom:20px;border:1px solid var(--border)}.stats-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:20px;margin-bottom:30px}.stat-card{background:var(--bg-card);padding:20px;border-radius:12px;box-shadow:var(--shadow);display:flex;flex-direction:column;border:1px solid var(--border)}.upload-area{border:2px dashed var(--text-muted);border-radius:12px;padding:40px;text-align:center;cursor:pointer;background:var(--bg-card)}.upload-area:hover{border-color:var(--primary);opacity:.9}.btn-primary{background:var(--primary);color:#fff;border:none;padding:10px 20px;border-radius:6px;cursor:pointer;font-weight:600;margin-top:10px}.menu-item{padding:10px;color:var(--text-muted);cursor:pointer;border-radius:8px;margin-bottom:5px}.menu-item:hover,.menu-item.active{background:#2563eb1a;color:var(--primary)}.recharts-responsive-container{width:100%!important;height:100%!important}.btn-secondary{background:var(--bg-card);color:var(--text-main);border:1px solid var(--border);padding:10px 20px;border-radius:6px;cursor:pointer;font-weight:600}.btn-secondary:hover{background:var(--primary);color:#fff}.fade-in{animation:fadeIn .3s ease-in}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}