:root {
    --sidebar-width: 268px;
    --navy: #12213f;
    --background: #f4f7fb;
    --ink: #172033;
    --muted: #718096;
    --line: #e4eaf2;
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--background); color: var(--ink); font-family: system-ui, sans-serif; }
.app-sidebar { position: fixed; inset: 0 auto 0 0; width: var(--sidebar-width); padding: 1.25rem; background: var(--navy); color: #fff; }
.brand { display: flex; gap: 0.75rem; align-items: center; margin-bottom: 1.5rem; }
.brand span { padding: 0.65rem; border-radius: 12px; background: #2878f0; }
.app-nav { display: grid; gap: 0.35rem; }
.app-nav a { padding: 0.8rem 1rem; border-radius: 10px; color: #bdc9dd; text-decoration: none; }
.app-nav a.active, .app-nav a:hover { background: rgba(255,255,255,0.1); color: #fff; }
.app-sidebar footer { position: absolute; bottom: 1.25rem; color: #9fb1d0; }
.app-main { min-height: 100vh; margin-left: var(--sidebar-width); }
.app-topbar { display: flex; height: 76px; align-items: center; gap: 1rem; padding: 0 2rem; background: #fff; border-bottom: 1px solid var(--line); }
.app-topbar small, .app-topbar strong { display: block; }
.environment-pill { margin-left: auto; padding: 0.4rem 0.8rem; border-radius: 999px; background: #fff3cd; color: #805b00; }
.app-content { padding: 2rem; }
.page-heading { margin-bottom: 1.5rem; }
.page-heading small { color: #2878f0; font-weight: 800; }
.page-heading h1 { margin: 0.2rem 0; }
.page-heading p { color: var(--muted); }
.metric-card, .panel { padding: 1.35rem; border: 1px solid var(--line); border-radius: 17px; background: #fff; }
.metric-card { border-left: 5px solid var(--accent); }
.metric-card span, .metric-card strong, .metric-card small { display: block; }
.metric-card strong { font-size: 2.1rem; }
.metric-card small { color: var(--muted); }
.tone-blue { --accent: #2f80ed; } .tone-purple { --accent: #8557e8; }
.tone-green { --accent: #16a06d; } .tone-amber { --accent: #e79c18; }
.tone-teal { --accent: #0c9caa; } .tone-red { --accent: #dc4e5b; }
.diagnostic-row { display: flex; justify-content: space-between; padding: 0.7rem 0; border-bottom: 1px solid var(--line); }
.check-ok { color: #08754d; } .check-fail { color: #b4232e; }
.app-footer { padding: 1rem 2rem; color: var(--muted); }
.sidebar-backdrop { display: none; }
@media (max-width: 992px) {
    .app-sidebar { transform: translateX(-100%); z-index: 1030; }
    .app-main { margin-left: 0; }
    .nav-open .app-sidebar { transform: translateX(0); }
    .nav-open .sidebar-backdrop { display: block; position: fixed; inset: 0; z-index: 1025; background: rgba(8,17,34,0.55); }
}