/* ============================================
   kodeku.id — Production-Grade Design System
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&family=Quicksand:wght@600;700&family=JetBrains+Mono:wght@400;500;600&display=swap');

:root {
  --bg-dark: #07090E;
  --bg-surface: #0F172A;
  --bg-card: #1E293B;
  --bg-elevated: #334155;
  --bg-input: #0B0F19;
  
  --primary: #2563EB;
  --primary-hover: #1D4ED8;
  --primary-glow: rgba(37, 99, 235, 0.35);
  
  --accent-teal: #10B981;
  --accent-green: #22C55E;
  --accent-purple: #8B5CF6;
  --accent-amber: #F59E0B;
  --accent-red: #EF4444;

  --text-main: #FFFFFF;
  --text-muted: #94A3B8;
  --text-dim: #64748B;
  
  --border: rgba(255, 255, 255, 0.08);
  --border-active: rgba(37, 99, 235, 0.5);
  
  --font-sans: 'Plus Jakarta Sans', sans-serif;
  --font-heading: 'Quicksand', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: var(--font-sans);
  background-color: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.6;
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
}

/* Layout Utilities */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.text-gradient {
  background: linear-gradient(135deg, #60A5FA 0%, #A78BFA 50%, #34D399 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.badge-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  background: rgba(37, 99, 235, 0.12);
  border: 1px solid rgba(37, 99, 235, 0.3);
  border-radius: 99px;
  color: #60A5FA;
  font-size: 0.8rem;
  font-weight: 600;
}

/* Navbar */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(7, 9, 14, 0.92);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  padding: 14px 0;
}
.nav-flex { display: flex; justify-content: space-between; align-items: center; }
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.3rem;
  font-weight: 800;
  color: #fff;
  text-decoration: none;
}
.logo-box {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--accent-purple));
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  color: #fff;
}
.nav-links { display: flex; align-items: center; gap: 20px; list-style: none; }
.nav-links a { color: var(--text-muted); text-decoration: none; font-weight: 500; font-size: 0.92rem; transition: var(--transition); }
.nav-links a:hover, .nav-links a.active { color: #fff; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  border: none;
  text-decoration: none;
  transition: var(--transition);
}
.btn-primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 4px 16px var(--primary-glow);
}
.btn-primary:hover { background: var(--primary-hover); transform: translateY(-2px); }
.btn-outline { background: transparent; color: var(--text-main); border: 1px solid var(--border); }
.btn-outline:hover { border-color: var(--primary); background: rgba(37, 99, 235, 0.1); }
.btn-success { background: var(--accent-teal); color: #fff; }
.btn-success:hover { background: #059669; }
.btn-amber { background: var(--accent-amber); color: #000; }
.btn-admin { background: rgba(139, 92, 246, 0.18); color: #C4B5FD; border: 1px solid rgba(139, 92, 246, 0.35); }

/* Hero Section */
.hero { padding: 60px 0 40px; text-align: center; }
.hero h1 { font-family: var(--font-heading); font-size: clamp(2.2rem, 5vw, 3.4rem); font-weight: 800; line-height: 1.2; margin: 20px 0; }
.hero p { font-size: 1.1rem; color: var(--text-muted); max-width: 680px; margin: 0 auto 32px; line-height: 1.7; }

/* Grid Cards */
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }

.card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  transition: var(--transition);
}
.card:hover { border-color: var(--border-active); transform: translateY(-4px); }

/* Course Card */
.course-card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: var(--transition);
}
.course-card:hover { border-color: var(--border-active); transform: translateY(-4px); box-shadow: 0 12px 30px rgba(0,0,0,0.5); }
.course-banner {
  height: 140px;
  background: linear-gradient(135deg, #1E293B, #0F172A);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3.5rem;
  position: relative;
  border-bottom: 1px solid var(--border);
}
.course-badge {
  position: absolute; top: 12px; right: 12px;
  background: rgba(16, 185, 129, 0.2); border: 1px solid rgba(16, 185, 129, 0.4);
  color: #34D399; font-size: 0.72rem; font-weight: 700; padding: 4px 10px; border-radius: 6px;
}
.course-body { padding: 20px; flex: 1; display: flex; flex-direction: column; }
.course-cat { font-size: 0.78rem; font-weight: 700; color: #60A5FA; text-transform: uppercase; margin-bottom: 6px; }
.course-title { font-size: 1.15rem; font-weight: 700; margin-bottom: 8px; line-height: 1.35; color: #fff; }
.course-desc { font-size: 0.88rem; color: var(--text-muted); margin-bottom: 16px; flex: 1; line-height: 1.5; }
.course-price { font-size: 1.25rem; font-weight: 800; color: #fff; }

/* Dicoding Classroom Layout */
.classroom-grid {
  display: grid;
  grid-template-columns: 320px 1fr;
  min-height: calc(100vh - 65px);
}
.sidebar-curriculum {
  background: var(--bg-surface);
  border-right: 1px solid var(--border);
  padding: 20px;
  overflow-y: auto;
}
.module-header {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin: 16px 0 8px;
}
.lesson-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.88rem;
  margin-bottom: 4px;
  transition: var(--transition);
  cursor: pointer;
}
.lesson-item:hover, .lesson-item.active {
  background: rgba(37, 99, 235, 0.15);
  color: #60A5FA;
  font-weight: 600;
}
.lesson-status { font-size: 0.75rem; margin-left: auto; color: var(--accent-teal); }

/* Text Content Reader & MDX Styles */
.reader-container { max-width: 860px; margin: 0 auto; padding: 30px; }
.reader-container p { margin-bottom: 20px; color: #CBD5E1; font-size: 1.02rem; line-height: 1.8; }
.reader-container h2 { font-family: var(--font-heading); font-size: 1.5rem; font-weight: 700; color: #fff; margin: 32px 0 16px; padding-bottom: 8px; border-bottom: 1px solid var(--border); }
.reader-container h3 { font-family: var(--font-heading); font-size: 1.2rem; font-weight: 700; color: #fff; margin: 24px 0 12px; }
.reader-container ul, .reader-container ol { margin: 0 0 24px 24px; color: #CBD5E1; }
.reader-container li { margin-bottom: 8px; }

/* Callout Boxes */
.callout {
  padding: 16px 20px;
  border-radius: var(--radius-md);
  margin: 24px 0;
  display: flex;
  gap: 14px;
  align-items: flex-start;
  font-size: 0.95rem;
}
.callout-info { background: rgba(37, 99, 235, 0.12); border-left: 4px solid var(--primary); color: #9EC5FE; }
.callout-tip { background: rgba(16, 185, 129, 0.12); border-left: 4px solid var(--accent-teal); color: #A3E635; }
.callout-warning { background: rgba(245, 158, 11, 0.12); border-left: 4px solid var(--accent-amber); color: #FDE047; }

/* Code Box & Monaco Sandbox */
.code-box {
  background: #0D1117;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  margin: 24px 0;
  overflow: hidden;
}
.code-header {
  background: #161B22;
  padding: 8px 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  border-bottom: 1px solid var(--border);
}
.code-editor-textarea {
  width: 100%;
  min-height: 120px;
  background: #0D1117;
  color: #E6EDE3;
  border: none;
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  outline: none;
  resize: vertical;
}
.code-output {
  background: #040D1A;
  border-top: 1px solid var(--border);
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  color: #4ADE80;
  min-height: 50px;
}

/* Modals */
.modal-overlay {
  position: fixed; inset: 0; background: rgba(0,0,0,0.85); backdrop-filter: blur(8px);
  z-index: 1000; display: none; align-items: center; justify-content: center;
}
.modal-overlay.active { display: flex; }
.modal-card {
  background: var(--bg-surface); border: 1px solid var(--border);
  border-radius: var(--radius-lg); width: 90%; max-width: 480px; padding: 24px;
}
.form-group { margin-bottom: 14px; }
.form-label { display: block; font-size: 0.82rem; font-weight: 600; color: var(--text-muted); margin-bottom: 4px; }
.form-input {
  width: 100%; padding: 10px 14px; background: var(--bg-input); border: 1px solid var(--border);
  border-radius: var(--radius-sm); color: #fff; font-size: 0.92rem;
}
.form-input:focus { border-color: var(--primary); outline: none; }

/* Admin Dashboard Table */
.table-wrap { width: 100%; overflow-x: auto; background: var(--bg-surface); border: 1px solid var(--border); border-radius: var(--radius-md); }
table { width: 100%; border-collapse: collapse; text-align: left; font-size: 0.88rem; }
th { background: #1E293B; padding: 12px 16px; color: var(--text-muted); font-weight: 600; border-bottom: 1px solid var(--border); }
td { padding: 12px 16px; border-bottom: 1px solid var(--border); }
tr:last-child td { border-bottom: none; }

/* States */
.empty-state { text-align: center; padding: 40px 20px; color: var(--text-muted); }
.loading-spinner {
  width: 32px; height: 32px; border: 3px solid rgba(255,255,255,0.1);
  border-top-color: var(--primary); border-radius: 50%; animation: spin 0.8s linear infinite; margin: 20px auto;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* Comprehensive Responsive Design System (Mobile, Tablet, Desktop) */

/* Tablet & Smaller Laptops (max-width: 1024px) */
@media (max-width: 1024px) {
  .container { padding: 0 20px; }
  .grid-3 { grid-template-columns: repeat(2, 1fr); gap: 20px; }
  .grid-2 { grid-template-columns: 1fr; gap: 20px; }
  .classroom-layout { grid-template-columns: 280px 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
}

/* Mobile Devices (max-width: 768px) */
@media (max-width: 768px) {
  /* Typography Scaling */
  h1 { font-size: 2rem !important; line-height: 1.25 !important; }
  h2 { font-size: 1.5rem !important; }
  h3 { font-size: 1.2rem !important; }
  p { font-size: 0.92rem !important; }

  /* Navbar Adjustments */
  .navbar { padding: 12px 0; }
  .nav-flex { flex-direction: column; align-items: flex-start !important; gap: 14px !important; }
  .nav-links { flex-wrap: wrap; justify-content: flex-start !important; gap: 10px !important; width: 100%; }
  .nav-links li { font-size: 0.88rem; }
  .logo { margin-right: 0 !important; }

  /* Hero Section */
  .hero { padding: 40px 0 30px; text-align: center; }
  .hero p { font-size: 0.95rem; }
  .hero .btn { width: 100%; justify-content: center; padding: 12px 18px !important; font-size: 0.95rem !important; }

  /* Grids to 1 Column */
  .grid-3, .grid-2, .course-grid, .stats-grid { grid-template-columns: 1fr !important; gap: 16px !important; }
  .course-card { margin-bottom: 0; }
  .course-body { padding: 18px 16px; }

  /* Classroom Layout Stack & Mobile Collapsible Sidebar Drawer */
  .classroom-layout { grid-template-columns: 1fr !important; display: flex; flex-direction: column; }
  #mobileSidebarBtnWrapper { display: block !important; }
  .sidebar {
    width: 100% !important; border-right: none !important; border-bottom: 1px solid var(--border);
    position: relative; top: 0; height: auto !important; padding: 16px !important; display: none;
  }
  .reader-area { padding: 20px 14px !important; width: 100% !important; }
  .reader-title { font-size: 1.4rem !important; }
  .reader-meta-row { flex-direction: column; align-items: flex-start; gap: 6px; }

  /* Touch Friendly Buttons & Modals */
  .btn, .btn-primary, .btn-outline, .btn-nav-mod {
    min-height: 44px; display: inline-flex; align-items: center; justify-content: center;
    width: 100%; border-radius: 10px; font-weight: 700;
  }
  .modal-card { width: 94% !important; padding: 20px 16px !important; max-height: 90vh; overflow-y: auto; }
  .module-nav-footer { flex-direction: column; gap: 10px; }
  .module-nav-footer button { width: 100%; }

  /* Code Sandbox & Tables */
  .sandbox-container { margin: 16px 0; }
  .sandbox-editor { font-size: 0.85rem !important; height: 140px; }
  .sandbox-header, .sandbox-footer { flex-direction: column; gap: 8px; align-items: flex-start; }
  .table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }
  table { font-size: 0.8rem; }
  th, td { padding: 10px 12px; white-space: nowrap; }

  /* Dashboard & Admin Panels */
  .dash-header { flex-direction: column; align-items: flex-start !important; padding: 20px 16px !important; }
  .dash-tabs { width: 100%; overflow-x: auto; flex-wrap: nowrap !important; padding-bottom: 8px; }
  .dash-tab-btn { flex-shrink: 0; padding: 8px 14px !important; font-size: 0.82rem !important; }
  .course-mini-card { flex-direction: column; align-items: flex-start !important; }
}

/* Category Filter Pills */
.cat-pill {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 8px 16px;
  border-radius: 30px;
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s ease;
}
.cat-pill.active, .cat-pill:hover {
  background: var(--primary);
  border-color: var(--primary);
  color: #FFF;
  box-shadow: 0 4px 14px rgba(99,102,241,0.4);
}