:root{--sidebar-bg:#0f1724;--accent:#2563eb;}
body{font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,sans-serif;background:#f3f6fb;margin:0}
.sidebar{width:260px;min-height:100vh;background:var(--sidebar-bg);color:#cbd5e1;padding:22px;box-shadow:4px 0 20px rgba(2,6,23,0.15)}
.sidebar .brand{color:white;font-weight:700;font-size:18px;margin-bottom:14px;display:flex;gap:10px;align-items:center}
.sidebar a{color:#cbd5e1;display:block;padding:10px 12px;border-radius:8px;text-decoration:none;margin-bottom:6px}
.sidebar a:hover{background:rgba(255,255,255,0.03);color:#fff}
.sidebar a.active{background:linear-gradient(90deg, rgba(255,255,255,0.03), rgba(255,255,255,0.02));color:#fff;border-left:4px solid var(--accent);padding-left:8px}
.main{padding:28px;min-height:100vh}
.card{border-radius:12px;box-shadow:0 8px 30px rgba(20,30,60,0.06);border:0}
.result-box{background:#ffffff;border-left:6px solid var(--accent);padding:18px;border-radius:8px;box-shadow:0 6px 14px rgba(16,24,40,0.04)}
.small-muted{color:#6b7280;font-size:13px}
@media(max-width:900px){.sidebar{position:relative;width:100%;min-height:auto}.main{padding:16px}}