:root {
    --bg-dark: #0f172a;
    --sidebar-bg: #020617;
    --card-bg: #1e293b;
    --accent-blue: #3b82f6;
    --text-main: #f8fafc;
    --text-dim: #94a3b8;
    --critical-red: #ef4444;
}

* { margin: 0; padding: 0; box-sizing: border-box; font-family: 'Segoe UI', sans-serif; }

body { background-color: var(--bg-dark); color: var(--text-main); }

.container { display: flex; min-height: 100vh; }

/* Sidebar */
.sidebar { width: 260px; background: var(--sidebar-bg); padding: 20px; border-right: 1px solid #334155; }
.logo { font-size: 24px; font-weight: bold; color: var(--accent-blue); margin-bottom: 40px; }
.logo span { color: white; }
.nav-links { list-style: none; }
.nav-links li { padding: 15px; cursor: pointer; color: var(--text-dim); transition: 0.3s; border-radius: 8px; }
.nav-links li:hover, .nav-links li.active { background: var(--accent-blue); color: white; }

/* Content */
.content { flex: 1; padding: 40px; overflow-y: auto; }
.section { display: none; }
.section.active { display: block; }

/* Cards & Charts */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 20px; margin: 20px 0; }
.card { background: var(--card-bg); padding: 20px; border-radius: 12px; border-left: 5px solid var(--accent-blue); }
.card.critical { border-left-color: var(--critical-red); }
.chart-container { background: var(--card-bg); padding: 20px; border-radius: 12px; height: 300px; }

/* Tables */
table { width: 100%; border-collapse: collapse; margin-top: 20px; background: var(--card-bg); border-radius: 10px; overflow: hidden; }
th, td { padding: 15px; text-align: left; border-bottom: 1px solid #334155; }
th { background: #0f172a; color: var(--accent-blue); }

/* Filters & Inputs */
.filters { display: flex; gap: 10px; margin-bottom: 20px; }
input, select { background: var(--card-bg); border: 1px solid #334155; color: white; padding: 10px; border-radius: 5px; }

/* Auth */
.auth-container { display: flex; justify-content: center; align-items: center; height: 60vh; }
.auth-box { background: var(--card-bg); padding: 40px; border-radius: 15px; width: 350px; text-align: center; }
.auth-box input { width: 100%; margin-bottom: 15px; }
.btn-primary { background: var(--accent-blue); color: white; border: none; padding: 12px; width: 100%; border-radius: 5px; cursor: pointer; }

#alert-box { background: #7f1d1d; color: #fca5a5; padding: 15px; border-radius: 8px; margin-bottom: 20px; }
.hidden { display: none; }