:root{--bg:#0f1117;--surface:#1a1d27;--surface2:#22263a;--border:#2e3352;--accent:#6c63ff;--accent2:#48cfad;--danger:#ff5c6c;--warn:#ffd166;--text:#e2e8f0;--muted:#7b8db0;--radius:12px}*{box-sizing:border-box;margin:0;padding:0}html{background:var(--bg)}body{background:var(--bg);color:var(--text);min-height:100vh;font-family:Segoe UI,system-ui,sans-serif}.app-container{width:100vw;height:100vh;display:flex;overflow:hidden}.sidebar{background:var(--surface);border-right:1px solid var(--border);flex-direction:column;flex-shrink:0;width:260px;display:flex}.sidebar-header{border-bottom:1px solid var(--border);padding:1.5rem}.sidebar-header h1{background:linear-gradient(135deg, var(--accent), var(--accent2));-webkit-text-fill-color:transparent;-webkit-background-clip:text;background-clip:text;font-size:1.25rem;font-weight:700}.sidebar-nav{flex:1;padding:1rem 0;overflow-y:auto}.nav-item{text-align:left;width:100%;color:var(--muted);cursor:pointer;background:0 0;border:none;border-left:3px 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