/* ═══════════════════════════════════════════════════
   مبادئ شبكات الحاسب — CSS الموحد لجميع الصفحات
   ═══════════════════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=Tajawal:wght@300;400;500;700;800;900&family=Cairo:wght@300;400;600;700;900&display=swap');

/* ─── VARIABLES ─── */
:root {
  --primary:        #6c2fa0;
  --primary-light:  #8b46c8;
  --primary-dark:   #4a1f6e;
  --accent:         #00c9b1;
  --accent2:        #ff6b35;
  --teal:           #0097a7;
  --bg:             #0b0d1a;
  --bg2:            #111327;
  --bg3:            #1a1d35;
  --card:           #161928;
  --card2:          #1e2240;
  --text:           #e8eaf6;
  --text-muted:     #8c90b5;
  --border:         rgba(108,47,160,0.25);
  --shadow:         0 8px 32px rgba(0,0,0,0.4);
  --radius:         16px;
  --radius-sm:      8px;
  --nav-h:          64px;
}

/* ─── RESET ─── */
*, *::before, *::after { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: 'Cairo', 'Tajawal', sans-serif;
  background: var(--bg);
  color: var(--text);
  direction: rtl;
  overflow-x: hidden;
  line-height: 1.8;
}

/* ─── SCROLLBAR ─── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--primary); border-radius: 3px; }

/* ════════════════════════════════════
   NAVIGATION
════════════════════════════════════ */
nav.main-nav {
  position: fixed;
  top: 0; right: 0; left: 0;
  z-index: 1000;
  background: rgba(11,13,26,0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  height: var(--nav-h);
}

.nav-inner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  gap: 1rem;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  font-size: 1.05rem;
  font-weight: 900;
  color: var(--accent);
  white-space: nowrap;
  flex-shrink: 0;
}

.nav-logo .logo-icon {
  width: 34px; height: 34px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1rem;
}

.nav-links {
  display: flex;
  gap: 0.2rem;
  list-style: none;
  flex-wrap: nowrap;
  align-items: center;
}

.nav-links a {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.4rem 0.75rem;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: 20px;
  transition: all 0.25s;
  white-space: nowrap;
}

.nav-links a:hover { color: #fff; background: rgba(108,47,160,0.3); }
.nav-links a.active { color: #fff; background: var(--primary); }

.nav-links a .nav-num {
  width: 18px; height: 18px;
  background: rgba(255,255,255,0.1);
  border-radius: 50%;
  font-size: 0.68rem;
  font-weight: 900;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}

.nav-links a.active .nav-num { background: rgba(255,255,255,0.25); }

/* hamburger */
.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 6px;
  background: none;
  border: none;
  color: var(--text);
}
.nav-hamburger span {
  display: block;
  width: 22px; height: 2px;
  background: var(--text-muted);
  border-radius: 2px;
  transition: all 0.3s;
}

/* mobile drawer */
.nav-drawer {
  display: none;
  position: fixed;
  top: var(--nav-h);
  right: 0; left: 0;
  background: var(--bg2);
  border-bottom: 1px solid var(--border);
  z-index: 999;
  padding: 1rem;
  flex-direction: column;
  gap: 0.4rem;
}
.nav-drawer.open { display: flex; }
.nav-drawer a {
  padding: 0.7rem 1rem;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  display: flex; align-items: center; gap: 0.5rem;
  transition: all 0.2s;
}
.nav-drawer a:hover, .nav-drawer a.active {
  background: var(--primary);
  color: #fff;
}

/* ════════════════════════════════════
   PAGE HERO (inner pages)
════════════════════════════════════ */
.page-hero {
  padding: calc(var(--nav-h) + 60px) 2rem 60px;
  background: radial-gradient(ellipse 80% 60% at 50% 0%, rgba(108,47,160,0.25) 0%, transparent 70%), var(--bg);
  text-align: center;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
}

.page-hero::before {
  content: '';
  position: absolute; inset: 0;
  background-image: radial-gradient(circle, rgba(108,47,160,0.09) 1px, transparent 1px);
  background-size: 40px 40px;
  pointer-events: none;
}

.page-hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.3rem 1.1rem;
  background: rgba(108,47,160,0.15);
  border: 1px solid rgba(108,47,160,0.35);
  border-radius: 30px;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--primary-light);
  letter-spacing: 0.08em;
  margin-bottom: 1rem;
}

.page-hero h1 {
  font-size: clamp(1.9rem, 4.5vw, 3.2rem);
  font-weight: 900;
  line-height: 1.2;
  margin-bottom: 1rem;
}

.page-hero h1 span { color: var(--accent); }

.page-hero p {
  font-size: 1rem;
  color: var(--text-muted);
  max-width: 620px;
  margin: 0 auto;
  line-height: 1.8;
}

/* breadcrumb */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
  justify-content: center;
}
.breadcrumb a { color: var(--accent); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb .sep { opacity: 0.4; }

/* sub-nav tabs (within a page) */
.sub-nav {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 1.75rem;
}

.sub-nav a {
  padding: 0.45rem 1.1rem;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 700;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--border);
  color: var(--text-muted);
  text-decoration: none;
  transition: all 0.25s;
}
.sub-nav a:hover, .sub-nav a.active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

/* ════════════════════════════════════
   MAIN CONTENT WRAPPER
════════════════════════════════════ */
.page-content {
  max-width: 1280px;
  margin: 0 auto;
  padding: 60px 2rem 80px;
}

/* ════════════════════════════════════
   SECTION BLOCK (anchor target)
════════════════════════════════════ */
.sec-block {
  margin-bottom: 4rem;
  scroll-margin-top: calc(var(--nav-h) + 20px);
}

.sec-block-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 2px solid var(--border);
}

.sec-block-header .sec-icon {
  width: 48px; height: 48px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.4rem;
  flex-shrink: 0;
}

.sec-block-header h2 {
  font-size: clamp(1.3rem, 3vw, 1.8rem);
  font-weight: 900;
  line-height: 1.25;
}
.sec-block-header h2 span { color: var(--accent); }

/* ════════════════════════════════════
   CONTENT BLOCK (sub-section)
════════════════════════════════════ */
.content-block {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2.25rem;
  margin-bottom: 1.5rem;
  position: relative;
  overflow: hidden;
}

.content-block::before {
  content: '';
  position: absolute;
  top: 0; right: 0;
  width: 100px; height: 100px;
  background: radial-gradient(circle, rgba(108,47,160,0.12) 0%, transparent 70%);
  pointer-events: none;
}

.content-block h3 {
  font-size: 1.15rem;
  font-weight: 800;
  margin-bottom: 1.1rem;
  color: var(--accent);
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.content-block h3 .dot {
  width: 10px; height: 10px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 50%;
  flex-shrink: 0;
}

.content-block p {
  color: var(--text-muted);
  line-height: 1.9;
  font-size: 0.94rem;
}

.content-block ul {
  list-style: none;
  margin-top: 0.75rem;
}
.content-block ul li {
  padding: 0.48rem 1.5rem 0.48rem 0;
  color: var(--text-muted);
  font-size: 0.91rem;
  line-height: 1.7;
  position: relative;
  border-bottom: 1px solid rgba(255,255,255,0.04);
}
.content-block ul li:last-child { border-bottom: none; }
.content-block ul li::before {
  content: '◆';
  position: absolute;
  right: 0;
  color: var(--primary-light);
  font-size: 0.5rem;
  top: 0.87rem;
}

/* ─── HIGHLIGHT BOX ─── */
.highlight-box {
  background: linear-gradient(135deg, rgba(108,47,160,0.12), rgba(0,201,177,0.07));
  border: 1px solid rgba(0,201,177,0.28);
  border-right: 4px solid var(--accent);
  border-radius: var(--radius-sm);
  padding: 1.5rem 1.75rem;
  margin-bottom: 1.25rem;
}
.highlight-box p {
  font-size: 0.97rem;
  line-height: 1.9;
  color: var(--text);
  font-weight: 500;
}

/* ─── NUMBERED LIST ─── */
.numbered-list { counter-reset: item; list-style: none; }
.numbered-list li {
  counter-increment: item;
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  padding: 0.7rem 0;
  border-bottom: 1px solid rgba(255,255,255,0.04);
  font-size: 0.92rem;
  color: var(--text-muted);
}
.numbered-list li:last-child { border-bottom: none; }
.numbered-list li::before {
  content: counter(item);
  min-width: 28px; height: 28px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-weight: 900; font-size: 0.78rem;
  flex-shrink: 0; margin-top: 0.05rem;
}

/* ════════════════════════════════════
   CARDS GRID
════════════════════════════════════ */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(270px, 1fr));
  gap: 1.25rem;
  margin-top: 1.25rem;
}

.info-card {
  background: var(--card2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: all 0.3s;
  position: relative;
  overflow: hidden;
}
.info-card::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transform: scaleX(0);
  transition: transform 0.3s;
}
.info-card:hover { border-color: rgba(108,47,160,0.55); transform: translateY(-4px); box-shadow: 0 12px 35px rgba(108,47,160,0.18); }
.info-card:hover::after { transform: scaleX(1); }

.info-card .card-icon {
  width: 46px; height: 46px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 11px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.3rem;
  margin-bottom: 1.1rem;
}
.info-card h3 { font-size: 1rem; font-weight: 800; margin-bottom: 0.6rem; color: var(--text); }
.info-card p  { font-size: 0.86rem; color: var(--text-muted); line-height: 1.75; }
.info-card ul { margin-top: 0.6rem; list-style: none; }
.info-card ul li {
  padding: 0.3rem 1rem 0.3rem 0;
  color: var(--text-muted);
  font-size: 0.83rem;
  position: relative;
}
.info-card ul li::before { content: '▶ '; color: var(--primary-light); font-size: 0.55rem; }

/* two-col grid */
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  margin-bottom: 1.25rem;
}

/* three-col grid */
.three-col {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
  margin-bottom: 1.25rem;
}

/* ════════════════════════════════════
   TABLE
════════════════════════════════════ */
.table-wrap {
  overflow-x: auto;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  margin: 1.25rem 0;
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.87rem;
}
thead { background: var(--primary-dark); }
thead th {
  padding: 0.9rem 1.1rem;
  text-align: right;
  font-weight: 700;
  color: #fff;
  white-space: nowrap;
}
tbody tr { border-bottom: 1px solid rgba(255,255,255,0.05); transition: background 0.2s; }
tbody tr:last-child { border-bottom: none; }
tbody tr:hover { background: rgba(108,47,160,0.08); }
tbody td {
  padding: 0.8rem 1.1rem;
  color: var(--text-muted);
  line-height: 1.55;
}
tbody td:first-child { font-weight: 700; color: var(--text); }

/* ════════════════════════════════════
   OSI LAYERS
════════════════════════════════════ */
.osi-layers { display: flex; flex-direction: column; gap: 0.5rem; margin: 1.25rem 0; }
.osi-layer {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  padding: 1.1rem 1.5rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--card2);
  transition: all 0.25s;
}
.osi-layer:hover { border-color: rgba(108,47,160,0.5); transform: translateX(-4px); }

.layer-num {
  width: 36px; height: 36px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-weight: 900; font-size: 0.88rem;
  flex-shrink: 0;
  color: #fff;
  margin-top: 2px;
}
.layer-info { flex: 1; }
.layer-name { font-weight: 800; font-size: 0.93rem; margin-bottom: 0.3rem; color: var(--text); }
.layer-desc { font-size: 0.82rem; color: var(--text-muted); line-height: 1.65; }
.layer-badge {
  padding: 0.22rem 0.7rem;
  border-radius: 20px;
  font-size: 0.72rem;
  font-weight: 700;
  background: rgba(255,255,255,0.07);
  color: var(--text-muted);
  white-space: nowrap;
  flex-shrink: 0;
  align-self: flex-start;
  margin-top: 4px;
}

.l7 { background: #5c6bc0; }
.l6 { background: #26a69a; }
.l5 { background: #66bb6a; }
.l4 { background: #ffa726; }
.l3 { background: #ef5350; }
.l2 { background: #ab47bc; }
.l1 { background: #8d6e63; }

/* ════════════════════════════════════
   NETWORK TYPE CARDS
════════════════════════════════════ */
.net-types-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(210px, 1fr));
  gap: 1.1rem;
  margin: 1.25rem 0;
}
.net-type-card {
  background: var(--card2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  text-align: center;
  transition: all 0.3s;
}
.net-type-card:hover { border-color: var(--accent); transform: translateY(-4px); }
.net-type-badge {
  display: inline-block;
  padding: 0.3rem 1rem;
  border-radius: 20px;
  font-weight: 900; font-size: 0.82rem;
  margin-bottom: 0.7rem;
  color: #fff;
}
.net-type-card h4 { font-size: 0.95rem; font-weight: 800; margin-bottom: 0.45rem; }
.net-type-card p  { font-size: 0.81rem; color: var(--text-muted); line-height: 1.65; }

/* badge colors */
.b-lan  { background: #6c2fa0; }
.b-wlan { background: #0097a7; }
.b-pan  { background: #e91e63; }
.b-man  { background: #ff6b35; }
.b-wan  { background: #4CAF50; }

/* ════════════════════════════════════
   TOPOLOGY GRID
════════════════════════════════════ */
.topo-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(170px, 1fr));
  gap: 1rem;
  margin: 1.25rem 0;
}
.topo-card {
  background: var(--card2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 1.25rem;
  text-align: center;
  transition: all 0.3s;
}
.topo-card:hover { border-color: var(--primary); transform: translateY(-3px); }
.topo-card .topo-icon { font-size: 1.8rem; margin-bottom: 0.4rem; }
.topo-card h4 { font-size: 0.87rem; font-weight: 700; color: var(--text); }
.topo-card p  { font-size: 0.76rem; color: var(--text-muted); margin-top: 0.25rem; }

/* ════════════════════════════════════
   THREAT & SOLUTION CARDS
════════════════════════════════════ */
.threat-card {
  background: var(--card2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.6rem;
  transition: all 0.3s;
}
.threat-card:hover { transform: translateY(-4px); box-shadow: 0 10px 28px rgba(0,0,0,0.3); }
.threat-card .t-icon { font-size: 1.8rem; margin-bottom: 0.75rem; display: block; }
.threat-card .t-tag {
  display: inline-block;
  padding: 0.18rem 0.65rem;
  border-radius: 10px;
  font-size: 0.7rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
}
.threat-card h4 { font-size: 0.95rem; font-weight: 800; margin-bottom: 0.5rem; color: var(--text); }
.threat-card p  { font-size: 0.84rem; color: var(--text-muted); line-height: 1.7; }
.tag-purple { background: rgba(108,47,160,0.2); color: #c58af9; }
.tag-red    { background: rgba(244,67,54,0.15); color: #ff6b6b; }
.tag-teal   { background: rgba(0,201,177,0.15); color: #00c9b1; }

.solution-card {
  background: var(--card2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.6rem;
  transition: all 0.3s;
}
.solution-card:hover { border-color: var(--accent); transform: translateY(-4px); }
.solution-card .sol-icon {
  width: 42px; height: 42px;
  border-radius: 10px;
  background: linear-gradient(135deg, rgba(0,201,177,0.18), rgba(108,47,160,0.18));
  border: 1px solid rgba(0,201,177,0.2);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.2rem;
  margin-bottom: 1rem;
}
.solution-card h4 { font-size: 0.93rem; font-weight: 800; margin-bottom: 0.5rem; color: var(--accent); }
.solution-card p  { font-size: 0.84rem; color: var(--text-muted); line-height: 1.7; }

/* ════════════════════════════════════
   CABLE CARD
════════════════════════════════════ */
.cable-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  margin-bottom: 1.25rem;
  position: relative;
  overflow: hidden;
}
.cable-card::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
}
.cable-card h3 { font-size: 1.1rem; font-weight: 800; margin-bottom: 0.9rem; color: var(--text); }
.cable-card h3 span { color: var(--accent); }
.cable-card p { color: var(--text-muted); line-height: 1.85; font-size: 0.92rem; }
.cable-card ul { margin-top: 0.75rem; list-style: none; }
.cable-card ul li {
  padding: 0.38rem 0;
  color: var(--text-muted);
  font-size: 0.87rem;
  border-bottom: 1px solid rgba(255,255,255,0.04);
}
.cable-card ul li:last-child { border-bottom: none; }
.cable-card ul li strong { color: var(--text); }
.cable-card ul li::before { content: '▸ '; color: var(--primary-light); }

/* ════════════════════════════════════
   IP TRAINING TABLE (colored cells)
════════════════════════════════════ */
.td-green { color: #00c9b1 !important; font-weight: 600; }
.td-class { color: var(--accent2) !important; font-weight: 700; text-align: center; }

/* ════════════════════════════════════
   DIVIDER
════════════════════════════════════ */
.sec-divider {
  width: 100%; height: 1px;
  background: linear-gradient(90deg, transparent, var(--border), transparent);
  margin: 2.5rem 0;
}

/* ════════════════════════════════════
   SCROLL TO TOP
════════════════════════════════════ */
.scroll-top {
  position: fixed;
  bottom: 2rem; left: 2rem;
  width: 44px; height: 44px;
  background: var(--primary);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  opacity: 0;
  transform: translateY(20px);
  transition: all 0.3s;
  border: none;
  color: #fff;
  font-size: 1.1rem;
  z-index: 800;
}
.scroll-top.visible { opacity: 1; transform: translateY(0); }
.scroll-top:hover { background: var(--accent); }

/* ════════════════════════════════════
   FOOTER
════════════════════════════════════ */
footer {
  text-align: center;
  padding: 2.5rem 2rem;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.84rem;
  background: var(--bg2);
  margin-top: 2rem;
}
footer strong { color: var(--accent); }
footer .footer-links {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 1rem;
}
footer .footer-links a {
  padding: 0.3rem 0.9rem;
  border-radius: 20px;
  background: rgba(255,255,255,0.05);
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.78rem;
  font-weight: 600;
  transition: all 0.2s;
}
footer .footer-links a:hover { background: var(--primary); color: #fff; }

/* ════════════════════════════════════
   ANIMATIONS
════════════════════════════════════ */
@keyframes fadeIn   { from { opacity:0 } to { opacity:1 } }
@keyframes slideUp  { from { opacity:0; transform:translateY(28px) } to { opacity:1; transform:translateY(0) } }

.anim-1 { animation: slideUp 0.7s ease 0.1s both; }
.anim-2 { animation: slideUp 0.7s ease 0.25s both; }
.anim-3 { animation: slideUp 0.7s ease 0.4s both; }
.anim-4 { animation: slideUp 0.7s ease 0.55s both; }

/* ════════════════════════════════════
   RESPONSIVE
════════════════════════════════════ */
@media (max-width: 900px) {
  .nav-links { display: none; }
  .nav-hamburger { display: flex; }
  .two-col, .three-col { grid-template-columns: 1fr; }
  .cards-grid { grid-template-columns: 1fr; }
  .net-types-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 600px) {
  .nav-inner { padding: 0 1rem; }
  .page-hero { padding: calc(var(--nav-h) + 40px) 1.25rem 40px; }
  .page-content { padding: 40px 1.25rem 60px; }
  .content-block { padding: 1.5rem; }
  .net-types-grid { grid-template-columns: 1fr; }
  .topo-grid { grid-template-columns: repeat(2, 1fr); }
  .scroll-top { bottom: 1rem; left: 1rem; }
  footer .footer-links { flex-direction: column; align-items: center; }
}