/* General Reset & Base */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background: linear-gradient(135deg, #1e1e2f, #2b2b3d);
  color: #f5f5f5;
  line-height: 1.6;
}

/* Header */
header {
  background-color: #14142b;
  padding: 20px 40px;
  box-shadow: 0 5px 15px rgba(0,0,0,0.3);
}

.header-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

header h1 {
  font-size: 2rem;
  color: #00ffc3;
  text-transform: uppercase;
  letter-spacing: 1px;
}

nav button.nav-btn {
  background-color: #00ffc3;
  border: none;
  padding: 10px 20px;
  margin-left: 10px;
  border-radius: 6px;
  color: #14142b;
  font-weight: bold;
  cursor: pointer;
  transition: 0.3s;
}

nav button.nav-btn:hover {
  background-color: #00d0a0;
  transform: translateY(-2px);
}

/* Sections */
.page-section {
  padding: 40px;
  display: none; /* will show only when selected */
  animation: fadeIn 0.6s ease-in-out;
}

.page-section.active {
  display: block;
}

h2 {
  font-size: 1.8rem;
  margin-bottom: 20px;
  color: #00ffc3;
}

/* Tables */
table {
  width: 100%;
  border-collapse: collapse;
  background-color: #1f1f2f;
  border-radius: 10px;
  overflow: hidden;
}

th, td {
  padding: 12px;
  text-align: left;
}

th {
  background-color: #2b2b3d;
  color: #00ffc3;
}

td {
  border-bottom: 1px solid #2b2b3d;
}

/* Alerts */
.alerts-list li {
  background-color: #ff4d6d;
  padding: 10px;
  border-radius: 5px;
  margin-bottom: 10px;
  font-weight: bold;
  color: #fff;
  list-style: none;
  box-shadow: 0 2px 6px rgba(0,0,0,0.4);
}

/* Diagrams */
.diagram-img {
  width: 100%;
  max-width: 600px;
  border-radius: 10px;
  box-shadow: 0 6px 15px rgba(0,0,0,0.5);
  margin-bottom: 20px;
}

.diagram-grid {
  display: flex;
  gap: 40px;
  flex-wrap: wrap;
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px);}
  to { opacity: 1; transform: translateY(0);}
}