:root {
  /* Renk Paleti - Canlı ve Net */
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #f1f5f9;
  
  --text-main: #0f172a; /* Çok belirgin siyah ton */
  --text-muted: #334155; /* Gri yok, solukluk yok, belirgin ton */
  
  --brand-primary: #3b82f6; /* Canlı Mavi */
  --brand-hover: #2563eb;
  --brand-success: #10b981;
  --brand-danger: #ef4444;
  --brand-warning: #f59e0b;
  
  --border-color: #e2e8f0;
  --radius-md: 12px;
  --radius-sm: 8px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

/* TEK EKRANA SIĞMA KURALI */
html, body {
  height: 100dvh;
  width: 100vw;
  overflow: hidden; /* Dış kaydırma yok */
  font-family: 'Outfit', -apple-system, sans-serif;
  background-color: var(--bg-secondary);
  color: var(--text-main);
  font-size: 14px;
}

/* UYGULAMA LAYOUT'U */
#sol-menu {
  width: 250px;
  background-color: var(--bg-primary);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
}

#ana-alan {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background-color: var(--bg-secondary);
}

#ust-header {
  height: 60px;
  background-color: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  padding: 0 1.5rem;
  justify-content: space-between;
}

#icerik-alani {
  flex: 1;
  overflow-y: auto; /* Sadece veriler sığmazsa iç alan kayar */
  padding: 1.5rem;
}

/* MENÜ ELEMANLARI */
.menu-item {
  padding: 1rem 1.5rem;
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 12px;
  transition: all 0.2s;
  border-left: 3px solid transparent;
}

.menu-item:hover, .menu-item.active {
  background-color: #eff6ff;
  color: var(--brand-primary);
  border-left-color: var(--brand-primary);
}

/* BUTONLAR */
.btn {
  padding: 0.6rem 1.2rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all 0.2s;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.btn-primary { background-color: var(--brand-primary); color: white; }
.btn-primary:hover { background-color: var(--brand-hover); box-shadow: 0 4px 6px -1px rgba(59, 130, 246, 0.2); transform: translateY(-1px); }

/* KARTLAR */
.card {
  background: var(--bg-primary);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  padding: 1.5rem;
}

/* MOBİL İÇİN HAMLE (TEK EKRAN KORUMASI) */
@media (max-width: 768px) {
  #sol-menu { display: none; /* Mobil menü toggle'a bağlanacak */ }
}