/* ==============================
   CCNA LEARN — CISCO DARK THEME
   ============================== */
@import url('https://fonts.googleapis.com/css2?family=Hind+Siliguri:wght@400;500;600;700&display=swap');

:root {
  --cisco-blue: #1ba0d7;
  --cisco-dark-blue: #00476b;
  --cisco-green: #6ec500;
  --cisco-orange: #ff6a00;
  --bg-primary: #0d1117;
  --bg-secondary: #161b22;
  --bg-card: #1c2128;
  --bg-hover: #21262d;
  --text-primary: #e6edf3;
  --text-secondary: #8b949e;
  --text-accent: #1ba0d7;
  --border: #30363d;
  --shadow: rgba(0,0,0,0.5);
  --success: #3fb950;
  --warning: #d29922;
  --danger: #f85149;
  --terminal-bg: #0c1014;
  --terminal-green: #39ff14;
  --terminal-text: #c0c0c0;
  --sidebar-w: 280px;
  --nav-h: 64px;
}

.light-mode {
  --bg-primary: #f0f4f8;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-hover: #e8edf2;
  --text-primary: #1a202c;
  --text-secondary: #4a5568;
  --border: #d1d9e0;
  --shadow: rgba(0,0,0,0.1);
  --terminal-bg: #1a1a2e;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: 'Inter', 'Hind Siliguri', sans-serif; background: var(--bg-primary); color: var(--text-primary); min-height: 100vh; transition: background 0.3s, color 0.3s; }

/* ---- TOPNAV ---- */
.topnav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 200;
  height: var(--nav-h);
  background: rgba(13,17,23,0.96);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  display: flex; align-items: center; gap: 1rem; padding: 0 1.5rem;
}
.nav-brand { display: flex; align-items: center; gap: 0.5rem; flex-shrink: 0; }
.brand-icon { font-size: 1.4rem; }
.brand-name { font-size: 1.1rem; font-weight: 700; color: var(--cisco-blue); }
.brand-tag { font-size: 0.7rem; background: var(--cisco-dark-blue); color: var(--cisco-blue); padding: 2px 8px; border-radius: 20px; font-weight: 600; }
.btn-back { margin-left: 0.5rem; padding: 4px 10px; background: var(--bg-hover); color: var(--text-secondary); border-radius: 6px; text-decoration: none; font-size: 0.8rem; font-weight: 500; transition: all 0.2s; border: 1px solid var(--border); }
.btn-back:hover { color: var(--text-primary); background: var(--border); }
.nav-links { display: flex; gap: 0.2rem; flex: 1; justify-content: center; }
.nav-link { padding: 6px 14px; border-radius: 8px; color: var(--text-secondary); text-decoration: none; font-size: 0.88rem; font-weight: 500; transition: all 0.2s; }
.nav-link:hover, .nav-link.active { color: var(--cisco-blue); background: rgba(27,160,215,0.1); }
.nav-actions { display: flex; align-items: center; gap: 0.5rem; margin-left: auto; }
.search-wrap { position: relative; }
.search-wrap input { background: var(--bg-card); border: 1px solid var(--border); color: var(--text-primary); border-radius: 8px; padding: 6px 12px; font-size: 0.85rem; width: 200px; outline: none; font-family: inherit; }
.search-wrap input:focus { border-color: var(--cisco-blue); }
.search-results { position: absolute; top: calc(100% + 4px); left: 0; right: 0; background: var(--bg-card); border: 1px solid var(--border); border-radius: 8px; max-height: 240px; overflow-y: auto; display: none; z-index: 100; box-shadow: 0 4px 20px var(--shadow); }
.search-results.open { display: block; }
.search-result-item { padding: 10px 14px; cursor: pointer; font-size: 0.85rem; border-bottom: 1px solid var(--border); }
.search-result-item:hover { background: var(--bg-hover); }
.theme-toggle, .hamburger { background: var(--bg-card); border: 1px solid var(--border); color: var(--text-primary); border-radius: 8px; padding: 6px 10px; cursor: pointer; font-size: 1rem; transition: all 0.2s; }
.theme-toggle:hover, .hamburger:hover { background: var(--bg-hover); }
.hamburger { display: none; }

/* ---- LAYOUT ---- */
.layout { display: flex; margin-top: var(--nav-h); min-height: calc(100vh - var(--nav-h)); }

/* ---- SIDEBAR ---- */
.sidebar { width: var(--sidebar-w); background: var(--bg-secondary); border-right: 1px solid var(--border); position: fixed; top: var(--nav-h); bottom: 0; left: 0; overflow-y: auto; z-index: 100; transition: transform 0.3s; }
.sidebar-header { padding: 1.2rem; border-bottom: 1px solid var(--border); }
.sidebar-header h3 { font-size: 0.9rem; font-weight: 700; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 0.6rem; }
.level-badges { display: flex; flex-direction: column; gap: 4px; }
.badge { font-size: 0.72rem; padding: 3px 8px; border-radius: 20px; font-weight: 600; display: inline-block; }
.badge.beginner { background: rgba(63,185,80,0.15); color: var(--success); }
.badge.intermediate { background: rgba(210,153,34,0.15); color: var(--warning); }
.badge.advanced { background: rgba(248,81,73,0.15); color: var(--danger); }
.day-list { list-style: none; padding: 0.5rem; }
.day-item { border-radius: 8px; margin-bottom: 2px; overflow: hidden; }
.day-item a { display: flex; align-items: center; gap: 0.6rem; padding: 9px 12px; text-decoration: none; color: var(--text-secondary); font-size: 0.83rem; transition: all 0.15s; border-radius: 8px; }
.day-item a:hover { background: var(--bg-hover); color: var(--text-primary); }
.day-item.active a { background: rgba(27,160,215,0.15); color: var(--cisco-blue); font-weight: 600; }
.day-item.completed a { color: var(--text-secondary); }
.day-item.completed a::before { content: '✓'; color: var(--success); margin-right: 4px; font-weight: 700; }
.day-num { font-size: 0.7rem; background: var(--bg-hover); color: var(--text-secondary); border-radius: 4px; padding: 1px 5px; font-family: 'JetBrains Mono', monospace; font-weight: 600; flex-shrink: 0; }
.day-item.active .day-num { background: var(--cisco-blue); color: white; }
.module-divider { padding: 8px 12px 4px; font-size: 0.7rem; font-weight: 700; color: var(--cisco-blue); text-transform: uppercase; letter-spacing: 1px; opacity: 0.8; }

/* ---- MAIN CONTENT ---- */
.main-content { margin-left: var(--sidebar-w); flex: 1; padding: 2rem; max-width: calc(100% - var(--sidebar-w)); overflow-x: hidden; }
.section { display: none; animation: fadeIn 0.3s ease; }
.section.active { display: block; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

/* ---- DASHBOARD HERO ---- */
.hero-banner { background: linear-gradient(135deg, rgba(27,160,215,0.08) 0%, rgba(0,71,107,0.1) 100%); border: 1px solid rgba(27,160,215,0.2); border-radius: 16px; padding: 2.5rem; display: grid; grid-template-columns: 1fr auto; gap: 2rem; align-items: center; margin-bottom: 2rem; position: relative; overflow: hidden; }
.hero-banner::before { content: ''; position: absolute; top: -80px; right: -80px; width: 300px; height: 300px; background: radial-gradient(circle, rgba(27,160,215,0.08) 0%, transparent 70%); border-radius: 50%; pointer-events: none; }
.cisco-badge { display: inline-block; background: linear-gradient(90deg, var(--cisco-dark-blue), var(--cisco-blue)); color: white; font-size: 0.62rem; font-weight: 800; letter-spacing: 2px; padding: 4px 12px; border-radius: 20px; margin-bottom: 0.8rem; }
.hero-text h1 { font-size: 2.2rem; font-weight: 800; line-height: 1.2; margin-bottom: 0.8rem; }
.hero-text h1 .bn-sub { font-family: 'Hind Siliguri', sans-serif; font-size: 1.3rem; color: var(--cisco-blue); display: block; }
.hero-text p { color: var(--text-secondary); line-height: 1.7; margin-bottom: 1.2rem; font-family: 'Hind Siliguri', sans-serif; font-size: 1rem; }
.btn-primary { background: linear-gradient(135deg, var(--cisco-blue), var(--cisco-dark-blue)); color: white; border: none; border-radius: 10px; padding: 12px 24px; font-size: 1rem; font-weight: 700; cursor: pointer; transition: all 0.2s; font-family: 'Hind Siliguri', sans-serif; }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 20px rgba(27,160,215,0.3); }
.hero-stats { display: grid; grid-template-columns: 1fr 1fr; gap: 0.8rem; }
.stat-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: 10px; padding: 1rem; text-align: center; }
.stat-num { display: block; font-size: 1.8rem; font-weight: 800; color: var(--cisco-blue); }
.stat-label { font-size: 0.72rem; color: var(--text-secondary); font-family: 'Hind Siliguri', sans-serif; }

/* ---- PROGRESS ---- */
.progress-section { background: var(--bg-card); border: 1px solid var(--border); border-radius: 12px; padding: 1.5rem; margin-bottom: 2rem; }
.progress-section h2 { font-size: 1rem; margin-bottom: 0.8rem; font-family: 'Hind Siliguri', sans-serif; }
.progress-bar-wrap { background: var(--bg-hover); border-radius: 20px; height: 10px; overflow: hidden; margin-bottom: 0.5rem; }
.progress-bar { background: linear-gradient(90deg, var(--cisco-blue), var(--cisco-green)); height: 100%; border-radius: 20px; transition: width 0.5s ease; }
#progressText { font-size: 0.85rem; color: var(--text-secondary); font-family: 'Hind Siliguri', sans-serif; }

/* ---- MODULE OVERVIEW ---- */
.module-overview h2 { font-size: 1.3rem; margin-bottom: 1.2rem; font-family: 'Hind Siliguri', sans-serif; }
.overview-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 1rem; }
.overview-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: 12px; padding: 1.4rem; cursor: pointer; transition: all 0.25s; position: relative; overflow: hidden; }
.overview-card:hover { border-color: var(--cisco-blue); transform: translateY(-3px); box-shadow: 0 8px 24px rgba(27,160,215,0.15); }
.overview-card::after { content: ''; position: absolute; top: 0; left: 0; width: 4px; height: 100%; background: linear-gradient(180deg, var(--cisco-blue), var(--cisco-dark-blue)); border-radius: 2px 0 0 2px; opacity: 0; transition: opacity 0.25s; }
.overview-card:hover::after { opacity: 1; }
.overview-card.ai-card::after { background: linear-gradient(180deg, var(--cisco-green), var(--cisco-blue)); }
.ov-icon { font-size: 2rem; margin-bottom: 0.5rem; }
.ov-module-badge { font-size: 0.68rem; font-weight: 700; color: var(--cisco-blue); background: rgba(27,160,215,0.1); padding: 2px 8px; border-radius: 20px; margin-bottom: 0.5rem; display: inline-block; }
.overview-card h3 { font-size: 1rem; margin-bottom: 0.4rem; }
.overview-card p { font-size: 0.85rem; color: var(--text-secondary); line-height: 1.5; font-family: 'Hind Siliguri', sans-serif; }

/* ---- LESSONS ---- */
.lesson-header-row { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 1rem; margin-bottom: 1.5rem; }
.lesson-header-row h2 { font-size: 1.3rem; font-family: 'Hind Siliguri', sans-serif; }
.module-filter { display: flex; gap: 0.4rem; flex-wrap: wrap; }
.filter-btn { background: var(--bg-card); border: 1px solid var(--border); color: var(--text-secondary); border-radius: 20px; padding: 5px 14px; font-size: 0.8rem; cursor: pointer; transition: all 0.2s; font-family: 'Hind Siliguri', sans-serif; }
.filter-btn:hover { border-color: var(--cisco-blue); color: var(--cisco-blue); }
.filter-btn.active { background: var(--cisco-blue); border-color: var(--cisco-blue); color: white; }
.lesson-detail { background: var(--bg-card); border: 1px solid var(--border); border-radius: 12px; padding: 2rem; min-height: 400px; }
.lesson-placeholder { display: flex; flex-direction: column; align-items: center; justify-content: center; height: 300px; color: var(--text-secondary); font-family: 'Hind Siliguri', sans-serif; }
.lesson-placeholder span { font-size: 3rem; margin-bottom: 1rem; }

/* Lesson content styles */
.lesson-title-bar { display: flex; align-items: flex-start; justify-content: space-between; gap: 1rem; margin-bottom: 1.5rem; flex-wrap: wrap; }
.lesson-title-bar h2 { font-size: 1.4rem; line-height: 1.3; font-family: 'Hind Siliguri', sans-serif; flex: 1; }
.lesson-meta { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.lesson-badge { font-size: 0.7rem; font-weight: 700; padding: 3px 10px; border-radius: 20px; }
.lesson-badge.module-1 { background: rgba(63,185,80,0.15); color: var(--success); }
.lesson-badge.module-2 { background: rgba(210,153,34,0.15); color: var(--warning); }
.lesson-badge.module-3 { background: rgba(27,160,215,0.15); color: var(--cisco-blue); }
.lesson-badge.module-4 { background: rgba(110,197,0,0.15); color: var(--cisco-green); }
.lesson-badge.module-5 { background: rgba(248,81,73,0.15); color: var(--danger); }
.lesson-badge.module-6 { background: rgba(255,106,0,0.15); color: var(--cisco-orange); }

.lesson-body { font-family: 'Hind Siliguri', sans-serif; line-height: 1.85; color: var(--text-primary); }
.lesson-body h3 { font-size: 1.1rem; margin: 1.5rem 0 0.6rem; color: var(--cisco-blue); font-family: 'Hind Siliguri', sans-serif; display: flex; align-items: center; gap: 0.4rem; }
.lesson-body p { margin-bottom: 0.8rem; font-size: 0.98rem; }
.lesson-body ul { margin: 0.6rem 0 0.8rem 1.2rem; }
.lesson-body ul li { margin-bottom: 0.4rem; font-size: 0.96rem; }
.lesson-body strong { color: var(--cisco-blue); }
.lesson-body .note-box { background: rgba(27,160,215,0.08); border-left: 3px solid var(--cisco-blue); padding: 0.8rem 1rem; border-radius: 0 8px 8px 0; margin: 1rem 0; font-size: 0.92rem; }
.lesson-body .warning-box { background: rgba(210,153,34,0.08); border-left: 3px solid var(--warning); padding: 0.8rem 1rem; border-radius: 0 8px 8px 0; margin: 1rem 0; font-size: 0.92rem; }
.lesson-body .tip-box { background: rgba(110,197,0,0.08); border-left: 3px solid var(--cisco-green); padding: 0.8rem 1rem; border-radius: 0 8px 8px 0; margin: 1rem 0; font-size: 0.92rem; }
.codeblock { background: var(--terminal-bg); border: 1px solid var(--border); border-radius: 8px; padding: 1rem; margin: 1rem 0; font-family: 'JetBrains Mono', monospace; font-size: 0.85rem; color: var(--terminal-green); overflow-x: auto; position: relative; }
.codeblock .cb-label { position: absolute; top: 6px; right: 10px; font-size: 0.65rem; color: var(--text-secondary); font-family: 'Inter', sans-serif; }
.codeblock span.cmd { color: #79c0ff; }
.codeblock span.comment { color: #8b949e; }
.codeblock span.val { color: var(--cisco-green); }
.codeblock span.prompt { color: var(--cisco-orange); }

.lesson-nav-row { display: flex; justify-content: space-between; margin-top: 2rem; padding-top: 1.5rem; border-top: 1px solid var(--border); }
.btn-lesson-nav { display: flex; align-items: center; gap: 0.5rem; background: var(--bg-hover); border: 1px solid var(--border); color: var(--text-primary); padding: 8px 16px; border-radius: 8px; cursor: pointer; font-size: 0.88rem; font-family: 'Hind Siliguri', sans-serif; transition: all 0.2s; }
.btn-lesson-nav:hover { border-color: var(--cisco-blue); color: var(--cisco-blue); }
.btn-complete { background: linear-gradient(135deg, var(--cisco-green), #4a9900); border: none; color: white; padding: 10px 20px; border-radius: 8px; cursor: pointer; font-size: 0.88rem; font-family: 'Hind Siliguri', sans-serif; font-weight: 700; transition: all 0.2s; }
.btn-complete:hover { transform: translateY(-2px); box-shadow: 0 4px 12px rgba(110,197,0,0.3); }
.btn-complete.done { background: var(--bg-hover); color: var(--success); border: 1px solid var(--success); }

/* ---- LAB ---- */
.lab-header { margin-bottom: 1.5rem; }
.lab-header h2 { font-size: 1.4rem; font-family: 'Hind Siliguri', sans-serif; margin-bottom: 0.4rem; }
.lab-desc { color: var(--text-secondary); font-size: 0.92rem; font-family: 'Hind Siliguri', sans-serif; }
.lab-workspace { display: grid; grid-template-columns: 240px 1fr; gap: 1.2rem; margin-bottom: 1.5rem; }
.lab-config-panel { background: var(--bg-card); border: 1px solid var(--border); border-radius: 12px; padding: 1.2rem; display: flex; flex-direction: column; gap: 1rem; }
.lab-config-panel h3 { font-size: 0.9rem; font-weight: 700; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 1px; font-family: 'Hind Siliguri', sans-serif; }
.lab-config-panel label { font-size: 0.8rem; color: var(--text-secondary); font-family: 'Hind Siliguri', sans-serif; display: block; margin-bottom: 0.4rem; }
.device-btns { display: flex; flex-direction: column; gap: 0.4rem; }
.dev-btn { background: var(--bg-hover); border: 1px solid var(--border); color: var(--text-secondary); border-radius: 8px; padding: 8px 12px; cursor: pointer; font-size: 0.83rem; font-weight: 600; transition: all 0.2s; text-align: left; }
.dev-btn:hover { border-color: var(--cisco-blue); color: var(--cisco-blue); }
.dev-btn.active { background: rgba(27,160,215,0.1); border-color: var(--cisco-blue); color: var(--cisco-blue); }
.scenario-btn { display: block; width: 100%; background: var(--bg-hover); border: 1px solid var(--border); color: var(--text-secondary); border-radius: 6px; padding: 7px 10px; cursor: pointer; font-size: 0.78rem; font-family: 'Hind Siliguri', sans-serif; text-align: left; margin-bottom: 4px; transition: all 0.2s; }
.scenario-btn:hover { border-color: var(--cisco-green); color: var(--cisco-green); }
.btn-clear-lab, .btn-reset-lab { width: 100%; background: var(--bg-hover); border: 1px solid var(--border); color: var(--text-secondary); border-radius: 8px; padding: 8px; cursor: pointer; font-size: 0.8rem; font-family: 'Hind Siliguri', sans-serif; transition: all 0.2s; margin-top: auto; }
.btn-clear-lab:hover { border-color: var(--danger); color: var(--danger); }
.btn-reset-lab:hover { border-color: var(--warning); color: var(--warning); }

/* Terminal */
.terminal-wrap { background: var(--terminal-bg); border: 1px solid var(--border); border-radius: 12px; overflow: hidden; display: flex; flex-direction: column; min-height: 480px; }
.terminal-titlebar { background: #1c2128; padding: 10px 14px; display: flex; align-items: center; gap: 0.8rem; border-bottom: 1px solid var(--border); }
.term-dots { display: flex; gap: 6px; }
.term-dots span { width: 12px; height: 12px; border-radius: 50%; }
.term-dots span:nth-child(1) { background: #ff5f57; }
.term-dots span:nth-child(2) { background: #febc2e; }
.term-dots span:nth-child(3) { background: #28c840; }
.term-title { font-size: 0.82rem; color: var(--text-secondary); font-family: 'JetBrains Mono', monospace; flex: 1; }
.term-hint { font-size: 0.72rem; color: var(--text-secondary); }
.term-hint code { background: rgba(255,255,255,0.1); padding: 1px 4px; border-radius: 3px; }
.terminal { flex: 1; padding: 1rem; font-family: 'JetBrains Mono', monospace; font-size: 0.88rem; line-height: 1.6; overflow-y: auto; cursor: text; }
.term-output { color: var(--terminal-text); white-space: pre-wrap; word-break: break-all; }
.term-output .line-cmd { color: var(--terminal-green); }
.term-output .line-err { color: var(--danger); }
.term-output .line-info { color: var(--cisco-blue); }
.term-output .line-success { color: var(--success); }
.term-output .line-warn { color: var(--warning); }
.term-input-line { display: flex; align-items: center; gap: 0.4rem; margin-top: 0.5rem; }
.term-prompt { color: var(--cisco-orange); font-weight: 700; white-space: nowrap; }
.term-input { flex: 1; background: transparent; border: none; color: var(--terminal-green); font-family: 'JetBrains Mono', monospace; font-size: 0.88rem; outline: none; caret-color: var(--terminal-green); }

.lab-guide { background: var(--bg-card); border: 1px solid var(--border); border-radius: 12px; padding: 1.5rem; }
.lab-guide h3 { font-size: 1rem; font-family: 'Hind Siliguri', sans-serif; margin-bottom: 1rem; }
.lab-guide-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 0.6rem; }
.lab-guide-item { background: var(--bg-hover); border: 1px solid var(--border); border-radius: 8px; padding: 10px 14px; font-size: 0.83rem; color: var(--text-secondary); font-family: 'Hind Siliguri', sans-serif; }
.lab-guide-item code { background: var(--terminal-bg); color: var(--cisco-blue); padding: 1px 6px; border-radius: 4px; font-family: 'JetBrains Mono', monospace; font-size: 0.78rem; display: block; margin-bottom: 4px; }

/* ---- COMMAND TABLE ---- */
#commands h2 { font-size: 1.3rem; font-family: 'Hind Siliguri', sans-serif; margin-bottom: 1rem; }
.cmd-filter-row { display: flex; flex-wrap: wrap; gap: 0.4rem; margin-bottom: 1.2rem; }
.cmd-cat-btn { background: var(--bg-card); border: 1px solid var(--border); color: var(--text-secondary); border-radius: 20px; padding: 5px 14px; font-size: 0.8rem; cursor: pointer; transition: all 0.2s; font-family: 'Hind Siliguri', sans-serif; }
.cmd-cat-btn.active { background: var(--cisco-blue); border-color: var(--cisco-blue); color: white; }
.cmd-cat-btn:hover { border-color: var(--cisco-blue); color: var(--cisco-blue); }
.cmd-table-wrap table { width: 100%; border-collapse: collapse; background: var(--bg-card); border-radius: 12px; overflow: hidden; }
.cmd-table-wrap th { background: var(--bg-secondary); padding: 10px 14px; font-size: 0.8rem; text-align: left; font-weight: 700; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 0.5px; border-bottom: 1px solid var(--border); }
.cmd-table-wrap td { padding: 10px 14px; border-bottom: 1px solid var(--border); font-size: 0.85rem; vertical-align: top; }
.cmd-table-wrap tr:last-child td { border-bottom: none; }
.cmd-table-wrap tr:hover td { background: var(--bg-hover); }
.cmd-table-wrap td:first-child { font-family: 'JetBrains Mono', monospace; color: var(--cisco-blue); font-size: 0.8rem; white-space: nowrap; }
.cmd-table-wrap td:last-child { font-family: 'Hind Siliguri', sans-serif; color: var(--text-secondary); line-height: 1.5; }
.cmd-mode-badge { font-size: 0.65rem; background: var(--bg-hover); color: var(--text-secondary); padding: 1px 6px; border-radius: 4px; display: inline-block; }

/* ---- CHEAT SHEET ---- */
#cheatsheet h2 { font-size: 1.3rem; font-family: 'Hind Siliguri', sans-serif; margin-bottom: 1.2rem; }
.cheatsheet-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 1rem; }
.cs-card { background: var(--bg-card); border: 1px solid var(--border); border-radius: 12px; overflow: hidden; }
.cs-card-header { background: linear-gradient(90deg, var(--cisco-dark-blue), var(--cisco-blue)); padding: 10px 14px; font-size: 0.85rem; font-weight: 700; color: white; font-family: 'Hind Siliguri', sans-serif; }
.cs-card-body { padding: 0.8rem; }
.cs-row { display: flex; justify-content: space-between; align-items: flex-start; gap: 0.5rem; padding: 5px 0; border-bottom: 1px solid var(--border); font-size: 0.8rem; }
.cs-row:last-child { border-bottom: none; }
.cs-cmd { font-family: 'JetBrains Mono', monospace; color: var(--cisco-blue); font-size: 0.75rem; flex: 1; }
.cs-desc { color: var(--text-secondary); font-family: 'Hind Siliguri', sans-serif; flex: 1; text-align: right; font-size: 0.78rem; }

/* ---- RESPONSIVE ---- */
@media (max-width: 900px) {
  .sidebar { transform: translateX(-100%); }
  .sidebar.open { transform: translateX(0); }
  .main-content { margin-left: 0; max-width: 100%; }
  .hamburger { display: block; }
  .hero-banner { grid-template-columns: 1fr; }
  .hero-stats { grid-template-columns: repeat(4, 1fr); }
  .lab-workspace { grid-template-columns: 1fr; }
  .brand-tag { display: none; }
}
@media (max-width: 600px) {
  .nav-links { display: none; }
  .search-wrap input { width: 130px; }
  .hero-text h1 { font-size: 1.6rem; }
  .hero-stats { grid-template-columns: 1fr 1fr; }
  .main-content { padding: 1rem; }
}
/* ========== QUIZ ========== */
.quiz-container {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 30px;
  max-width: 800px;
  margin: 0 auto;
}
.quiz-intro { text-align: center; }
.quiz-intro h3 { color: var(--cisco-blue); margin-bottom: 10px; font-size: 1.5rem; }
.quiz-intro p { margin-bottom: 20px; color: var(--text-light); }

.quiz-progress-bar {
  height: 8px;
  background: var(--bg);
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 15px;
}
.quiz-progress-fill {
  height: 100%;
  background: var(--cisco-blue);
  width: 0%;
  transition: width 0.3s ease;
}
.quiz-status {
  display: flex;
  justify-content: space-between;
  font-size: 0.9rem;
  color: var(--text-light);
  margin-bottom: 20px;
  font-family: var(--font-mono);
}
.quiz-question-text {
  font-size: 1.2rem;
  margin-bottom: 20px;
  line-height: 1.5;
}
.quiz-options {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 25px;
}
.quiz-option {
  background: var(--bg);
  border: 1px solid var(--border);
  padding: 15px 20px;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.2s;
  display: flex;
  align-items: center;
}
.quiz-option:hover {
  border-color: var(--cisco-blue);
  background: rgba(27, 160, 215, 0.05);
}
.quiz-option.selected {
  border-color: var(--cisco-blue);
  background: rgba(27, 160, 215, 0.1);
}
.quiz-option.correct {
  border-color: var(--success);
  background: rgba(46, 213, 115, 0.1);
}
.quiz-option.wrong {
  border-color: var(--danger);
  background: rgba(255, 71, 87, 0.1);
}

.quiz-actions {
  display: flex;
  justify-content: flex-end;
}
.quiz-result { text-align: center; }
.score-circle {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  border: 8px solid var(--cisco-blue);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2rem;
  font-weight: 700;
  margin: 20px auto;
  color: var(--cisco-blue);
}
.review-answers {
  margin-top: 30px;
  text-align: left;
  border-top: 1px solid var(--border);
  padding-top: 20px;
  max-height: 400px;
  overflow-y: auto;
  margin-bottom: 20px;
}
.review-item {
  background: var(--bg);
  padding: 15px;
  border-radius: 8px;
  margin-bottom: 15px;
  border-left: 4px solid var(--border);
}
.review-item.review-correct { border-left-color: var(--success); }
.review-item.review-wrong { border-left-color: var(--danger); }
.review-item p { margin-bottom: 8px; }
.review-explanation {
  font-size: 0.9rem;
  color: var(--text-light);
  background: rgba(255, 255, 255, 0.05);
  padding: 10px;
  border-radius: 4px;
}

.btn-primary, .btn-secondary {
  padding: 10px 20px;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 600;
  font-family: inherit;
  transition: opacity 0.2s;
}
.btn-primary { background: var(--cisco-blue); color: #fff; }
.btn-secondary { background: var(--surface); color: var(--text); border: 1px solid var(--border); }
.btn-primary:hover, .btn-secondary:hover { opacity: 0.9; }
.btn-secondary:disabled { opacity: 0.5; cursor: not-allowed; }