/* ==========================================================================
   ✨ PYTHON LERNPORTAL – NEXT-GEN DESIGN SYSTEM & UI/UX FRAMEWORK ✨
   ==========================================================================
   Inspiriert von führenden Plattformen (Vercel, Linear, Stripe, Brilliant).
   Optimiert für Lesbarkeit, kognitive Entlastung und responsive Interaktion.
   ========================================================================== */

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

:root {
  /* Farb-Tokens */
  --primary: #4f46e5;
  --primary-hover: #4338ca;
  --primary-gradient: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
  --primary-light: #eef2ff;
  --primary-glow: rgba(79, 70, 229, 0.25);

  --secondary: #0284c7;
  --secondary-light: #f0f9ff;
  
  --emerald: #059669;
  --emerald-light: #ecfdf5;
  --emerald-gradient: linear-gradient(135deg, #059669 0%, #0d9488 100%);
  
  --purple: #7c3aed;
  --purple-light: #f5f3ff;
  --purple-gradient: linear-gradient(135deg, #7c3aed 0%, #c026d3 100%);

  --amber: #d97706;
  --amber-light: #fffbeb;
  --amber-gradient: linear-gradient(135deg, #d97706 0%, #f59e0b 100%);

  --danger: #e11d48;
  --danger-light: #fff1f2;

  --success: #10b981;
  --success-light: #ecfdf5;
  --warning: #f59e0b;
  --warning-light: #fffbeb;

  /* Neutrals & Surfaces */
  --bg-main: #f8fafc;
  --bg-surface: #ffffff;
  --bg-subtle: #f1f5f9;
  --bg-dark: #090d16;
  --bg-card-dark: #0f172a;
  --bg-code: #0b0f19;

  --border-subtle: #e2e8f0;
  --border-focus: #cbd5e1;
  --border-dark: rgba(255, 255, 255, 0.08);

  --text-main: #0f172a;
  --text-body: #334155;
  --text-muted: #64748b;
  --text-code: #e2e8f0;

  /* Typography */
  --font-sans: 'Plus Jakarta Sans', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, Monaco, monospace;

  /* Shadows & Depth */
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06), 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -1px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 12px 24px -4px rgba(0, 0, 0, 0.08), 0 4px 8px -2px rgba(0, 0, 0, 0.04);
  --shadow-xl: 0 20px 30px -6px rgba(0, 0, 0, 0.12), 0 8px 12px -4px rgba(0, 0, 0, 0.06);

  /* Radii */
  --radius-xs: 4px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  /* Animations */
  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}

/* ==========================================================================
   Base & Reset
   ========================================================================== */

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-main);
  color: var(--text-body);
  line-height: 1.7;
  font-size: 16px;
  padding-bottom: 80px;
}

/* ==========================================================================
   Header & Hero
   ========================================================================== */

header {
  background: linear-gradient(145deg, #090d16 0%, #171c2c 50%, #1e1b4b 100%);
  color: #ffffff;
  padding: 40px 20px 45px 20px;
  margin-bottom: 35px;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

header::before {
  content: "";
  position: absolute;
  top: -40%;
  right: -10%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.25) 0%, rgba(124, 58, 237, 0) 70%);
  border-radius: 50%;
  pointer-events: none;
}

.header-container {
  max-width: 960px;
  margin: 0 auto;
  position: relative;
  z-index: 2;
}

.header-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(8px);
  padding: 6px 14px;
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: #c7d2fe;
  border: 1px solid rgba(255, 255, 255, 0.15);
  margin-bottom: 14px;
}

header h1 {
  font-size: 2.3rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  margin-bottom: 10px;
  line-height: 1.2;
  background: linear-gradient(135deg, #ffffff 30%, #c7d2fe 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

header p {
  font-size: 1.12rem;
  color: #94a3b8;
  max-width: 750px;
  line-height: 1.6;
}

/* Nav Links & Breadcrumbs */
.nav-links {
  display: flex;
  gap: 10px;
  margin-bottom: 20px;
  font-size: 0.88rem;
  flex-wrap: wrap;
  align-items: center;
}

.nav-links a {
  color: #cbd5e1;
  text-decoration: none;
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(6px);
  padding: 6px 14px;
  border-radius: var(--radius-full);
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  font-weight: 600;
}

.nav-links a:hover {
  background: rgba(255, 255, 255, 0.2);
  color: #ffffff;
  transform: translateY(-1px);
  border-color: rgba(255, 255, 255, 0.25);
}

/* ==========================================================================
   Main Container & Cards
   ========================================================================== */

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 20px;
}

.card {
  background: var(--bg-surface);
  border-radius: var(--radius-md);
  padding: 30px;
  margin-bottom: 28px;
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-normal);
}

.card:hover {
  box-shadow: var(--shadow-md);
}

.card h2 {
  font-size: 1.45rem;
  font-weight: 800;
  letter-spacing: -0.015em;
  color: var(--text-main);
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  gap: 10px;
  border-bottom: 2px solid var(--bg-subtle);
  padding-bottom: 10px;
}

.card h3 {
  font-size: 1.2rem;
  font-weight: 700;
  margin: 24px 0 12px 0;
  color: var(--text-main);
}

.card p {
  margin-bottom: 16px;
  color: var(--text-body);
}

/* ==========================================================================
   Live Search & Filter Bar
   ========================================================================== */

.search-bar-container {
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 12px 18px;
  margin-bottom: 30px;
  display: flex;
  align-items: center;
  gap: 12px;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-fast);
}

.search-bar-container:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.search-icon {
  font-size: 1.2rem;
  color: var(--text-muted);
}

.search-input {
  flex: 1;
  border: none;
  outline: none;
  font-family: var(--font-sans);
  font-size: 1rem;
  color: var(--text-main);
  background: transparent;
}

.search-input::placeholder {
  color: var(--text-muted);
}

.search-count {
  background: var(--primary-light);
  color: var(--primary);
  font-size: 0.8rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  display: none;
}

/* ==========================================================================
   Roadmap Cards & Grids
   ========================================================================== */

.roadmap-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 22px;
  margin: 25px 0 40px 0;
}

.roadmap-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 22px;
  text-decoration: none;
  color: var(--text-main);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: all var(--transition-smooth);
  box-shadow: var(--shadow-xs);
  position: relative;
  overflow: hidden;
}

.roadmap-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}

.roadmap-number {
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  display: inline-flex;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  margin-bottom: 12px;
}

.roadmap-title {
  font-size: 1.18rem;
  font-weight: 800;
  margin-bottom: 8px;
  color: var(--text-main);
  line-height: 1.35;
}

.roadmap-desc {
  font-size: 0.92rem;
  color: var(--text-muted);
  margin-bottom: 16px;
  flex: 1;
  line-height: 1.5;
}

.roadmap-footer {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 10px;
}

.card-quick-links a {
  transition: all var(--transition-fast);
  text-decoration: none;
}

.card-quick-links a:hover {
  background: var(--primary) !important;
  color: white !important;
  transform: translateY(-1px);
}

/* Track Badges */
.track-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.track-1-badge { background: var(--emerald-light); color: var(--emerald); }
.track-2-badge { background: var(--primary-light); color: var(--primary); }
.track-3-badge { background: var(--purple-light); color: var(--purple); }

/* ==========================================================================
   Didactic Callout Boxes
   ========================================================================== */

.box {
  border-radius: var(--radius-md);
  padding: 20px 24px;
  margin: 22px 0;
  border-left: 5px solid;
  position: relative;
  box-shadow: var(--shadow-xs);
}

.box-title {
  font-weight: 800;
  font-size: 1.05rem;
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.box-analogie {
  background-color: var(--purple-light);
  border-left-color: var(--purple);
  color: #4c1d95;
}

.box-tipp {
  background-color: var(--primary-light);
  border-left-color: var(--primary);
  color: #312e81;
}

.box-warning {
  background-color: var(--warning-light);
  border-left-color: var(--warning);
  color: #78350f;
}

.box-danger {
  background-color: var(--danger-light);
  border-left-color: var(--danger);
  color: #7f1d1d;
}

.box-success {
  background-color: var(--success-light);
  border-left-color: var(--success);
  color: #064e3b;
}

/* ==========================================================================
   Code Blocks & Syntax Highlights
   ========================================================================== */

.code-container {
  background-color: var(--bg-code);
  border-radius: var(--radius-md);
  margin: 20px 0;
  overflow: hidden;
  box-shadow: var(--shadow-md);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.code-header {
  background-color: #060911;
  color: #94a3b8;
  padding: 10px 18px;
  font-size: 0.82rem;
  font-family: var(--font-mono);
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.code-dots {
  display: flex;
  gap: 6px;
}

.code-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}
.dot-red { background-color: #ef4444; }
.dot-yellow { background-color: #f59e0b; }
.dot-green { background-color: #10b981; }

pre {
  margin: 0;
  padding: 18px 20px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.94rem;
  color: var(--text-code);
  line-height: 1.6;
}

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background-color: #f1f5f9;
  color: #e11d48;
  padding: 2px 7px;
  border-radius: var(--radius-xs);
  font-weight: 500;
}

pre code {
  background-color: transparent;
  color: inherit;
  padding: 0;
}

/* Copy Button on Code Header */
.btn-copy-code {
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #cbd5e1;
  padding: 3px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-family: var(--font-sans);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-copy-code:hover {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

.btn-copy-code.copied {
  background: var(--success);
  color: white;
  border-color: var(--success);
}

/* Syntax Highlights */
.kw { color: #f472b6; font-weight: bold; }
.fn { color: #60a5fa; }
.str { color: #a7f3d0; }
.num { color: #fbbf24; }
.cm { color: #64748b; font-style: italic; }
.var { color: #cbd5e1; }
.attr { color: #38bdf8; }

/* Keyboard Badges */
kbd {
  display: inline-block;
  padding: 3px 8px;
  font-family: var(--font-mono);
  font-size: 0.82em;
  font-weight: 700;
  color: #334155;
  background-color: #f8fafc;
  border: 1px solid #cbd5e1;
  border-bottom: 2px solid #94a3b8;
  border-radius: 4px;
  box-shadow: 0 1px 1px rgba(0,0,0,0.08);
  margin: 0 2px;
}

/* ==========================================================================
   Interactive Task Checklists
   ========================================================================== */

.task-list {
  list-style: none;
  margin: 18px 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.task-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 14px 18px;
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-xs);
}

.task-item:hover {
  border-color: var(--primary);
  background: var(--primary-light);
}

.task-item.task-completed {
  background: var(--emerald-light);
  border-color: #a7f3d0;
  opacity: 0.85;
}

.task-item.task-completed .task-label {
  text-decoration: line-through;
  color: #065f46;
}

.task-checkbox {
  width: 20px;
  height: 20px;
  margin-top: 2px;
  accent-color: var(--primary);
  cursor: pointer;
  flex-shrink: 0;
}

.task-label {
  flex: 1;
  font-size: 0.96rem;
  line-height: 1.5;
}

/* Details & Accordions */
details {
  background: #f8fafc;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 14px 18px;
  margin: 14px 0;
  transition: all var(--transition-fast);
}

details[open] {
  background: #ffffff;
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
}

summary {
  font-weight: 700;
  cursor: pointer;
  color: var(--primary);
  user-select: none;
  display: flex;
  align-items: center;
  gap: 8px;
}

summary:hover {
  color: var(--primary-hover);
}

.details-content {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--border-subtle);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  background: var(--primary);
  color: white;
  text-decoration: none;
  font-weight: 700;
  font-size: 0.92rem;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-sm);
}

.btn:hover {
  background: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background: #ffffff;
  color: var(--text-main);
  border: 1px solid var(--border-subtle);
}

.btn-secondary:hover {
  background: var(--bg-subtle);
  border-color: var(--border-focus);
}

.footer-nav {
  display: flex;
  justify-content: space-between;
  margin-top: 40px;
  gap: 16px;
  flex-wrap: wrap;
}

/* ==========================================================================
   GAMIFICATION HUD & BATTLE-PASS STYLES
   ========================================================================== */

.hud-card {
  background: linear-gradient(145deg, #090d16 0%, #0f172a 100%);
  color: #f8fafc;
  border-radius: var(--radius-lg);
  padding: 28px;
  margin-bottom: 35px;
  box-shadow: var(--shadow-xl);
  border: 1px solid rgba(255, 255, 255, 0.1);
  position: relative;
  overflow: hidden;
}

.hud-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, #6366f1 0%, #06b6d4 50%, #10b981 100%);
}

.hud-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 20px;
}

.hud-user {
  display: flex;
  align-items: center;
  gap: 16px;
}

.hud-avatar {
  font-size: 2.4rem;
  background: rgba(99, 102, 241, 0.2);
  border: 2px solid #818cf8;
  width: 60px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.5);
}

.hud-name {
  font-size: 1.35rem;
  font-weight: 800;
  color: #ffffff;
}

.hud-title {
  font-size: 0.95rem;
  color: #94a3b8;
}

.hud-rank {
  color: #fbbf24;
  font-weight: 800;
}

.hud-stats {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.hud-stat-box {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 10px 16px;
  border-radius: var(--radius-sm);
  display: flex;
  flex-direction: column;
  align-items: center;
  min-width: 95px;
  backdrop-filter: blur(6px);
}

.hud-stat-value {
  font-size: 1.15rem;
  font-weight: 800;
  color: #38bdf8;
}

.hud-stat-label {
  font-size: 0.72rem;
  color: #94a3b8;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  font-weight: 700;
}

.hud-progress-container {
  margin: 18px 0;
}

.hud-progress-labels {
  display: flex;
  justify-content: space-between;
  font-size: 0.88rem;
  color: #cbd5e1;
  margin-bottom: 8px;
  font-weight: 600;
}

.hud-progress-bar-bg {
  background: rgba(255, 255, 255, 0.1);
  height: 16px;
  border-radius: 8px;
  overflow: hidden;
  position: relative;
}

.hud-progress-bar-fill {
  background: linear-gradient(90deg, #10b981 0%, #06b6d4 50%, #6366f1 100%);
  height: 100%;
  border-radius: 8px;
  transition: width 0.8s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: 0 0 15px rgba(16, 185, 129, 0.6);
}

.hud-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 18px;
  padding-top: 18px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.hud-btn {
  background: linear-gradient(135deg, #4f46e5 0%, #6366f1 100%);
  color: white;
  border: none;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  font-weight: 800;
  font-size: 0.9rem;
  cursor: pointer;
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  box-shadow: 0 4px 15px rgba(79, 70, 229, 0.4);
}

.hud-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(79, 70, 229, 0.6);
}

.hud-cli-tip {
  font-size: 0.85rem;
  color: #94a3b8;
}

.hud-cli-tip code {
  background: rgba(0, 0, 0, 0.4);
  color: #38bdf8;
  border: 1px solid rgba(255, 255, 255, 0.1);
}

/* Trophy Room */
.trophy-room {
  margin-top: 22px;
  padding-top: 18px;
  border-top: 1px dashed rgba(255, 255, 255, 0.12);
}

.trophy-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
  margin-top: 14px;
}

.trophy-card {
  padding: 16px;
  border-radius: var(--radius-md);
  display: flex;
  gap: 14px;
  align-items: flex-start;
  transition: all var(--transition-fast);
}

.trophy-unlocked {
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid #10b981;
  box-shadow: 0 0 15px rgba(16, 185, 129, 0.2);
}

.trophy-locked {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.06);
  opacity: 0.6;
}

.trophy-icon {
  font-size: 2rem;
  flex-shrink: 0;
}

.trophy-info {
  flex: 1;
}

.trophy-title {
  font-size: 1rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 4px;
}

.trophy-desc {
  font-size: 0.84rem;
  color: #94a3b8;
  line-height: 1.4;
  margin-bottom: 6px;
}

.trophy-badge-status {
  font-size: 0.75rem;
  font-weight: 800;
  text-transform: uppercase;
}

.trophy-unlocked .trophy-badge-status { color: #10b981; }
.trophy-locked .trophy-badge-status { color: #64748b; }

/* ==========================================================================
   Parsons Problems Widgets
   ========================================================================== */

.parsons-box {
  background: #ffffff;
  border: 2px solid #e0e7ff;
  border-radius: var(--radius-lg);
  padding: 24px;
  margin: 28px 0;
  box-shadow: var(--shadow-sm);
}

.parsons-header {
  margin-bottom: 16px;
}

.parsons-title {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 6px;
}

.parsons-badge {
  background: var(--amber-light);
  color: var(--amber);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  font-weight: 800;
}

.parsons-instruction {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin: 0;
}

.parsons-board {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin: 18px 0;
}

.parsons-line {
  display: flex;
  align-items: center;
  gap: 14px;
  background: #f8fafc;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  cursor: grab;
  transition: all var(--transition-fast);
}

.parsons-line:hover {
  border-color: var(--primary);
  background: var(--primary-light);
  transform: translateX(2px);
}

.parsons-handle {
  color: var(--text-muted);
  font-size: 1.2rem;
  cursor: grab;
  user-select: none;
}

.parsons-code {
  flex: 1;
}

.parsons-code code {
  background: transparent;
  color: var(--text-main);
  font-size: 0.96rem;
  padding: 0;
}

.parsons-actions {
  display: flex;
  gap: 6px;
}

.btn-parsons-move {
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  padding: 4px 10px;
  font-size: 0.8rem;
  cursor: pointer;
  color: var(--text-muted);
  font-weight: 700;
  transition: all var(--transition-fast);
}

.btn-parsons-move:hover:not(:disabled) {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

.btn-parsons-move:disabled {
  opacity: 0.25;
  cursor: not-allowed;
}

.parsons-controls {
  display: flex;
  gap: 12px;
  margin-top: 18px;
  flex-wrap: wrap;
}

/* ==========================================================================
   Certificate Modal
   ========================================================================== */

.certificate-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(15, 23, 42, 0.88);
  backdrop-filter: blur(8px);
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.certificate-container {
  background: #ffffff;
  border-radius: var(--radius-lg);
  padding: 24px;
  max-width: 780px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.35);
}

.certificate-border {
  border: 6px double #d97706;
  border-radius: var(--radius-sm);
  padding: 35px 25px;
  text-align: center;
  background: #fffdfa;
}

.certificate-badge {
  font-size: 0.9rem;
  font-weight: 800;
  letter-spacing: 2px;
  color: #b45309;
  margin-bottom: 12px;
}

.certificate-headline {
  font-size: 2.2rem;
  color: #1e293b;
  margin-bottom: 8px;
  font-weight: 800;
}

.certificate-sub {
  color: var(--text-muted);
  font-size: 1rem;
  margin-bottom: 12px;
}

.certificate-student-name {
  font-size: 2rem;
  font-weight: 800;
  color: var(--primary);
  text-decoration: underline;
  text-decoration-color: #fbbf24;
  text-underline-offset: 8px;
  margin: 16px 0;
}

.certificate-text {
  color: var(--text-muted);
  font-size: 1rem;
}

.certificate-track-title {
  font-size: 1.45rem;
  color: #0f172a;
  margin: 10px 0;
  font-weight: 800;
}

.certificate-desc {
  font-size: 0.92rem;
  color: #64748b;
  max-width: 580px;
  margin: 0 auto 24px auto;
  line-height: 1.5;
}

.certificate-meta {
  display: flex;
  justify-content: space-around;
  font-size: 0.95rem;
  color: #334155;
  margin: 24px 0;
  padding: 14px 0;
  border-top: 1px solid #e2e8f0;
  border-bottom: 1px solid #e2e8f0;
}

.certificate-seal {
  font-size: 1.05rem;
  font-weight: 800;
  color: #b45309;
  letter-spacing: 1px;
}

.certificate-actions {
  display: flex;
  justify-content: flex-end;
  gap: 12px;
  margin-top: 20px;
}

@media print {
  body * { visibility: hidden; }
  .certificate-container, .certificate-container * { visibility: visible; }
  .certificate-overlay { position: static; background: transparent; padding: 0; }
  .certificate-actions { display: none; }
}

/* Responsive */
@media (max-width: 768px) {
  header h1 { font-size: 1.8rem; }
  .card { padding: 20px; }
  .footer-nav { flex-direction: column; }
  .footer-nav .btn { width: 100%; justify-content: center; }
  .hud-header { flex-direction: column; align-items: flex-start; }
  .hud-stats { width: 100%; justify-content: space-between; }
  .roadmap-grid { grid-template-columns: 1fr; }
}

/* ==========================================================================
   APP LAYOUT & LEFT SIDEBAR NAVIGATION
   ========================================================================== */

body {
  padding-left: 300px;
  transition: padding-left var(--transition-smooth);
}

.app-sidebar {
  width: 300px;
  height: 100vh;
  position: fixed;
  top: 0;
  left: 0;
  background: #090d16;
  color: #f8fafc;
  border-right: 1px solid rgba(255, 255, 255, 0.08);
  display: flex;
  flex-direction: column;
  z-index: 1000;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.sidebar-brand {
  padding: 20px 22px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(255, 255, 255, 0.02);
}

.sidebar-brand-link {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: white;
}

.sidebar-brand-logo {
  font-size: 1.8rem;
  background: rgba(99, 102, 241, 0.2);
  border: 1px solid rgba(99, 102, 241, 0.4);
  width: 42px;
  height: 42px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
}

.sidebar-brand-title {
  font-size: 1.05rem;
  font-weight: 800;
  color: #ffffff;
  letter-spacing: -0.01em;
}

.sidebar-brand-sub {
  font-size: 0.75rem;
  color: #94a3b8;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.sidebar-quick-nav {
  padding: 12px 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(0, 0, 0, 0.2);
}

.sidebar-quick-link {
  color: #94a3b8;
  text-decoration: none;
  font-size: 0.82rem;
  font-weight: 600;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.sidebar-quick-link:hover {
  background: rgba(255, 255, 255, 0.08);
  color: #ffffff;
}

.sidebar-content {
  flex: 1;
  overflow-y: auto;
  padding: 16px 14px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.sidebar-content::-webkit-scrollbar {
  width: 5px;
}

.sidebar-content::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.15);
  border-radius: 3px;
}

.sidebar-section {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.sidebar-section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.78rem;
  font-weight: 800;
  color: #94a3b8;
  text-transform: uppercase;
  letter-spacing: 0.6px;
  padding: 4px 8px;
}

.sidebar-section-badge {
  padding: 2px 6px;
  border-radius: var(--radius-full);
  font-size: 0.7rem;
  font-weight: 800;
}

.sidebar-nav-list {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.sidebar-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  color: #cbd5e1;
  text-decoration: none;
  font-size: 0.86rem;
  font-weight: 600;
  transition: all var(--transition-fast);
  border-left: 3px solid transparent;
}

.sidebar-item:hover {
  background: rgba(255, 255, 255, 0.06);
  color: #ffffff;
  border-left-color: rgba(255, 255, 255, 0.3);
}

.sidebar-item.active {
  background: rgba(99, 102, 241, 0.18);
  color: #ffffff;
  border-left-color: var(--primary);
  font-weight: 700;
}

.sidebar-item-icon {
  font-size: 1rem;
  flex-shrink: 0;
}

.sidebar-item-text {
  flex: 1;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.sidebar-solved-badge {
  font-size: 0.78rem;
}

.sidebar-footer {
  padding: 14px 16px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(0, 0, 0, 0.3);
}

.sidebar-user-card {
  display: flex;
  align-items: center;
  gap: 10px;
}

.sidebar-user-avatar {
  font-size: 1.4rem;
  background: rgba(99, 102, 241, 0.2);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--primary);
}

.sidebar-user-info {
  flex: 1;
}

.sidebar-user-name {
  font-size: 0.85rem;
  font-weight: 800;
  color: white;
}

.sidebar-user-title {
  font-size: 0.72rem;
  color: #94a3b8;
}

.sidebar-user-xp {
  font-size: 0.82rem;
  font-weight: 800;
  color: #38bdf8;
}

/* Mobile Drawer Toggle & Overlay */
.sidebar-mobile-toggle {
  display: none;
  position: fixed;
  bottom: 20px;
  left: 20px;
  z-index: 1001;
  background: var(--primary-gradient);
  color: white;
  border: none;
  padding: 12px 20px;
  border-radius: var(--radius-full);
  font-size: 0.95rem;
  font-weight: 800;
  cursor: pointer;
  box-shadow: var(--shadow-xl);
  backdrop-filter: blur(8px);
}

.sidebar-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(15, 23, 42, 0.7);
  backdrop-filter: blur(4px);
  z-index: 999;
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.sidebar-overlay.active {
  display: block;
  opacity: 1;
}

@media (max-width: 1024px) {
  body {
    padding-left: 0;
  }

  .app-sidebar {
    transform: translateX(-100%);
    transition: transform var(--transition-smooth);
  }

  .app-sidebar.open {
    transform: translateX(0);
  }

  .sidebar-mobile-toggle {
    display: inline-flex;
    align-items: center;
    gap: 6px;
  }
}