/* ═══════════════════════════════════════════════════
   COURS JAVASCRIPT — apprendre-javascript.fr
   Design System & Theme
   ═══════════════════════════════════════════════════ */

/* ─── Variables ─── */
:root {
  /* Backgrounds */
  --bg:            #0a0e17;
  --bg2:           #0f1420;
  --bg3:           #141a28;
  --bg-card:       #111827;
  --bg-card-hover: #161e2e;
  --editor-bg:     #0d1117;

  /* Surfaces (glassmorphism) */
  --surface:       rgba(255,255,255,0.025);
  --surface2:      rgba(255,255,255,0.05);
  --surface3:      rgba(255,255,255,0.08);
  --glass:         rgba(15,20,32,0.85);
  --glass-border:  rgba(255,255,255,0.06);

  /* Borders */
  --border:        rgba(255,255,255,0.06);
  --border2:       rgba(255,255,255,0.1);
  --border3:       rgba(255,255,255,0.15);

  /* Text */
  --text:          rgba(255,255,255,0.92);
  --text2:         rgba(255,255,255,0.55);
  --text3:         rgba(255,255,255,0.35);

  /* Accents */
  --cyan:          #00d2ff;
  --cyan-dim:      #00a8cc;
  --cyan-glow:     rgba(0,210,255,0.25);
  --cyan-bg:       rgba(0,210,255,0.06);
  --magenta:       #ff2d95;
  --magenta-glow:  rgba(255,45,149,0.2);
  --green:         #00ff88;
  --green-bg:      rgba(0,255,136,0.08);
  --yellow:        #ffd600;
  --yellow-bg:     rgba(255,214,0,0.08);
  --red:           #ff4757;
  --red-bg:        rgba(255,71,87,0.06);
  --violet:        #a855f7;
  --violet-bg:     rgba(168,85,247,0.08);
  --orange:        #ff6b35;

  /* Badge colors */
  --js-color:      #ffd600;
  --tf-color:      #ff6b35;

  /* Fonts */
  --font:          'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
  --mono:          'JetBrains Mono', 'Fira Code', 'Consolas', monospace;

  /* Layout */
  --topbar-h:      52px;
  --sidebar-w:     270px;
  --radius-sm:     6px;
  --radius-md:     10px;
  --radius-lg:     14px;
  --radius-xl:     18px;

  /* Transitions */
  --ease:          cubic-bezier(0.4, 0, 0.2, 1);
}

/* ─── Reset ─── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow: hidden;
  height: 100vh;
  height: 100dvh;
}

::selection { background: rgba(0,210,255,0.3); color: #fff; }

::-webkit-scrollbar { width: 5px; height: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius: 10px; }
::-webkit-scrollbar-thumb:hover { background: rgba(255,255,255,0.18); }


/* ═══════════════════════════════════════════════════
   TOPBAR
   ═══════════════════════════════════════════════════ */
.topbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 24px; height: var(--topbar-h);
  background: var(--glass);
  backdrop-filter: blur(24px); -webkit-backdrop-filter: blur(24px);
  border-bottom: 1px solid var(--glass-border);
}

.topbar-left { display: flex; align-items: center; gap: 14px; }

.topbar-logo {
  font-size: 1.05rem; font-weight: 700;
  color: var(--text); text-decoration: none;
  display: flex; align-items: center; gap: 8px;
  transition: color 0.25s var(--ease);
}
.topbar-logo:hover { color: var(--cyan); }
.topbar-logo .dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 12px var(--cyan-glow), 0 0 4px var(--cyan);
  flex-shrink: 0;
}

.topbar-sep { width: 1px; height: 20px; background: var(--border2); }

.topbar-page {
  font-size: 0.76rem; font-weight: 600;
  color: var(--js-color); letter-spacing: 0.04em;
  padding: 3px 10px; border-radius: var(--radius-sm);
  background: var(--yellow-bg);
  border: 1px solid rgba(255,214,0,0.12);
}

.topbar-nav { display: flex; gap: 4px; }
.topbar-link {
  font-size: 0.74rem; font-weight: 500; color: var(--text2);
  text-decoration: none; padding: 6px 12px; border-radius: var(--radius-md);
  transition: all 0.2s var(--ease);
}
.topbar-link:hover { color: var(--text); background: var(--surface2); }
.topbar-link.active { color: var(--cyan); background: var(--cyan-bg); }

.topbar-right { display: flex; align-items: center; gap: 10px; }

.back-link {
  font-size: 0.74rem; font-weight: 500; color: var(--text2);
  text-decoration: none; padding: 6px 14px; border-radius: var(--radius-md);
  border: 1px solid var(--border2); background: var(--surface);
  transition: all 0.25s var(--ease);
}
.back-link:hover {
  color: var(--cyan); border-color: rgba(0,210,255,0.25);
  background: var(--cyan-bg);
}

.mobile-menu-btn {
  display: none; background: none; border: 1px solid var(--border2);
  border-radius: var(--radius-sm); padding: 8px 10px; cursor: pointer;
  flex-direction: column; gap: 3px; align-items: center;
}
.mobile-menu-btn span {
  display: block; width: 16px; height: 1.5px; background: var(--text2);
  border-radius: 1px; transition: all 0.2s var(--ease);
}


/* ═══════════════════════════════════════════════════
   LAYOUT
   ═══════════════════════════════════════════════════ */
.page-layout {
  display: grid;
  grid-template-columns: var(--sidebar-w) 1fr;
  height: 100vh; height: 100dvh;
  padding-top: var(--topbar-h);
}


/* ═══════════════════════════════════════════════════
   SIDEBAR
   ═══════════════════════════════════════════════════ */
.sidebar {
  background: var(--bg2);
  border-right: 1px solid var(--border);
  padding: 16px 0 30px;
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: rgba(255,255,255,0.08) transparent;
}

.sidebar-mobile-header {
  display: none; justify-content: space-between; align-items: center;
  padding: 14px 16px; border-bottom: 1px solid var(--border);
}
.sidebar-mobile-title { font-size: 0.95rem; font-weight: 700; color: #fff; }
.sidebar-mobile-close {
  background: none; border: 1px solid var(--border); color: var(--text2);
  padding: 5px 12px; border-radius: var(--radius-sm); font-family: var(--font);
  font-size: 0.74rem; cursor: pointer; transition: all 0.2s var(--ease);
}
.sidebar-mobile-close:hover { color: var(--text); border-color: var(--border2); }

/* Search */
.sidebar-search {
  position: relative; margin: 0 14px 14px; 
}
.search-icon {
  position: absolute; left: 10px; top: 50%; transform: translateY(-50%);
  color: var(--text3); pointer-events: none;
}
.search-input {
  width: 100%; padding: 8px 12px 8px 34px;
  background: var(--surface2); border: 1px solid var(--border);
  border-radius: var(--radius-md); color: var(--text);
  font-family: var(--font); font-size: 0.76rem;
  outline: none; transition: all 0.2s var(--ease);
}
.search-input::placeholder { color: var(--text3); }
.search-input:focus {
  border-color: rgba(0,210,255,0.3);
  background: var(--surface3);
  box-shadow: 0 0 0 2px rgba(0,210,255,0.08);
}

.sidebar-title {
  font-size: 0.63rem; font-weight: 700;
  text-transform: uppercase; letter-spacing: 0.12em;
  color: var(--text3); padding: 0 20px; margin-bottom: 8px;
}

/* Categories */
.category-list { padding: 0 10px; margin-bottom: 16px; }

.category-item {
  display: flex; align-items: center; gap: 8px; width: 100%;
  padding: 8px 10px; font-family: var(--font); font-size: 0.76rem;
  color: var(--text2); background: transparent; border: 1px solid transparent;
  border-radius: var(--radius-md); cursor: pointer;
  transition: all 0.2s var(--ease); margin-bottom: 2px; text-align: left;
}
.category-item:hover { background: var(--surface2); color: var(--text); border-color: var(--border); }
.category-item.active {
  background: var(--cyan-bg); color: var(--cyan);
  border-color: rgba(0,210,255,0.18);
}
.cat-icon { font-size: 0.9rem; flex-shrink: 0; width: 22px; text-align: center; }
.cat-count {
  margin-left: auto; font-size: 0.6rem; font-weight: 700;
  font-family: var(--mono); color: var(--text3);
  background: var(--surface2); padding: 1px 6px; border-radius: 99px;
  min-width: 20px; text-align: center;
}
.category-item.active .cat-count { background: rgba(0,210,255,0.12); color: var(--cyan); }

/* Stats */
.sidebar-stats {
  margin: 0 14px; padding: 16px;
  background: var(--bg-card); border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: 0 2px 12px rgba(0,0,0,0.2);
}
.sidebar-stats h4 {
  font-size: 0.63rem; font-weight: 700; color: var(--text3);
  text-transform: uppercase; letter-spacing: 0.1em; margin-bottom: 10px;
}
.stat-row {
  display: flex; justify-content: space-between;
  font-size: 0.76rem; margin-bottom: 5px; color: var(--text2);
}
.stat-row .val {
  font-weight: 700; color: var(--cyan); font-family: var(--mono); font-size: 0.82rem;
}
.progress-track {
  height: 4px; background: var(--surface3); border-radius: 99px;
  margin-top: 10px; overflow: hidden;
}
.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--cyan), var(--green));
  border-radius: 99px; transition: width 0.6s var(--ease);
  box-shadow: 0 0 8px var(--cyan-glow);
}
.progress-text {
  font-size: 0.66rem; color: var(--text3); margin-top: 6px; text-align: right;
}


/* ═══════════════════════════════════════════════════
   MAIN AREA
   ═══════════════════════════════════════════════════ */
.main-area {
  display: flex; flex-direction: column; overflow: hidden;
}

/* ─── Tabs bar ─── */
.tabs-bar {
  display: flex; gap: 2px; padding: 8px 24px 0;
  background: var(--bg2); border-bottom: 1px solid var(--border);
  flex-shrink: 0; overflow-x: auto;
}
.tab {
  display: flex; align-items: center; gap: 6px;
  font-family: var(--font); font-size: 0.76rem; font-weight: 600;
  color: var(--text3); background: transparent; border: none;
  padding: 10px 16px; cursor: pointer;
  border-bottom: 2px solid transparent;
  transition: all 0.2s var(--ease);
  white-space: nowrap;
}
.tab:hover { color: var(--text2); }
.tab.active { color: var(--cyan); border-bottom-color: var(--cyan); }
.tab-icon { font-size: 0.85rem; }

/* ─── Tab content ─── */
.tab-content {
  display: none; flex: 1; overflow-y: auto; padding: 20px 24px 40px;
}
.tab-content.active { display: block; }

/* ─── Content header ─── */
.content-header {
  display: flex; align-items: flex-start; justify-content: space-between;
  margin-bottom: 20px; gap: 16px; flex-wrap: wrap;
}
.page-title {
  font-size: 1.4rem; font-weight: 700; line-height: 1.3;
  background: linear-gradient(135deg, #fff 60%, var(--cyan-dim));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.page-subtitle { font-size: 0.8rem; color: var(--text2); margin-top: 2px; }
.header-actions { display: flex; gap: 8px; flex-shrink: 0; }


/* ═══════════════════════════════════════════════════
   BUTTONS
   ═══════════════════════════════════════════════════ */
.btn-primary {
  font-family: var(--font); font-size: 0.74rem; font-weight: 700;
  padding: 8px 18px; border-radius: var(--radius-md);
  border: none; cursor: pointer;
  background: var(--cyan); color: #000;
  box-shadow: 0 0 12px var(--cyan-glow);
  transition: all 0.25s var(--ease);
  display: inline-flex; align-items: center; gap: 6px;
}
.btn-primary:hover {
  background: #00e0ff;
  box-shadow: 0 0 24px var(--cyan-glow), 0 2px 8px rgba(0,210,255,0.3);
  transform: translateY(-1px);
}

.btn-secondary {
  font-family: var(--font); font-size: 0.74rem; font-weight: 600;
  padding: 8px 18px; border-radius: var(--radius-md);
  border: 1px solid var(--border2); cursor: pointer;
  background: var(--surface2); color: var(--text2);
  transition: all 0.2s var(--ease);
  display: inline-flex; align-items: center; gap: 6px;
}
.btn-secondary:hover { background: var(--surface3); color: var(--text); border-color: var(--border3); }

.action-btn {
  font-family: var(--font); font-size: 0.68rem; font-weight: 600;
  padding: 5px 12px; border-radius: var(--radius-sm);
  border: 1px solid var(--border); background: transparent;
  color: var(--text3); cursor: pointer; transition: all 0.2s var(--ease);
}
.action-btn:hover { background: var(--surface2); color: var(--text2); }


/* ═══════════════════════════════════════════════════
   TAB: APPRENDRE — Lessons
   ═══════════════════════════════════════════════════ */
.lessons-grid { display: flex; flex-direction: column; gap: 16px; }

.lesson-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); overflow: hidden;
  transition: all 0.25s var(--ease);
}
.lesson-card:hover {
  border-color: var(--border2);
  box-shadow: 0 4px 20px rgba(0,0,0,0.3);
}

.lesson-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 20px; cursor: pointer; user-select: none;
  transition: background 0.2s var(--ease);
}
.lesson-header:hover { background: var(--surface); }

.lesson-header-left { display: flex; align-items: center; gap: 12px; }
.lesson-icon { font-size: 1.2rem; }
.lesson-title { font-size: 0.92rem; font-weight: 600; color: var(--text); }
.lesson-badge {
  font-size: 0.56rem; font-weight: 700; text-transform: uppercase;
  letter-spacing: 0.06em; padding: 2px 8px; border-radius: 99px;
  background: var(--yellow-bg); color: var(--js-color);
  border: 1px solid rgba(255,214,0,0.12);
}
.lesson-chevron {
  font-size: 0.7rem; color: var(--text3);
  transition: transform 0.25s var(--ease);
}
.lesson-card.open .lesson-chevron { transform: rotate(90deg); }

.lesson-body {
  display: none; padding: 0 20px 20px;
  border-top: 1px solid var(--border);
}
.lesson-card.open .lesson-body { display: block; }

.lesson-explanation {
  font-size: 0.82rem; color: var(--text2); line-height: 1.7;
  padding: 16px 0;
}
.lesson-explanation code {
  background: rgba(0,210,255,0.07); color: var(--cyan);
  padding: 1px 6px; border-radius: 4px;
  font-family: var(--mono); font-size: 0.76rem;
  border: 1px solid rgba(0,210,255,0.1);
}
.lesson-explanation strong { color: var(--text); font-weight: 600; }

.lesson-code-block {
  background: var(--editor-bg); border: 1px solid var(--border);
  border-radius: var(--radius-md); overflow: hidden; margin-top: 12px;
}
.lesson-code-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 8px 14px; border-bottom: 1px solid var(--border);
  background: rgba(0,0,0,0.2);
}
.lesson-code-lang {
  font-size: 0.62rem; font-weight: 600; color: var(--text3);
  text-transform: uppercase; letter-spacing: 0.08em;
}
.lesson-run-btn {
  font-family: var(--font); font-size: 0.64rem; font-weight: 700;
  padding: 4px 10px; border-radius: var(--radius-sm);
  border: none; cursor: pointer;
  background: var(--cyan); color: #000;
  transition: all 0.2s var(--ease);
}
.lesson-run-btn:hover { background: #00e0ff; box-shadow: 0 0 10px var(--cyan-glow); }

.lesson-code-pre {
  padding: 14px 16px; font-family: var(--mono); font-size: 0.76rem;
  color: var(--text); line-height: 1.6; overflow-x: auto;
  white-space: pre; tab-size: 2;
}

.lesson-output {
  margin-top: 8px; padding: 10px 14px;
  background: rgba(0,255,136,0.04); border: 1px solid rgba(0,255,136,0.1);
  border-radius: var(--radius-md); font-family: var(--mono);
  font-size: 0.74rem; color: var(--green); display: none;
}
.lesson-output.visible { display: block; }


/* ═══════════════════════════════════════════════════
   TAB: PRATIQUER — Editor
   ═══════════════════════════════════════════════════ */
.editor-split {
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 0; flex: 1; min-height: 0;
  border: 1px solid var(--border); border-radius: var(--radius-lg);
  overflow: hidden;
}

.editor-panel { display: flex; flex-direction: column; overflow: hidden; }
.editor-panel { border-right: 1px solid var(--border); }
.console-panel { display: flex; flex-direction: column; overflow: hidden; }

.panel-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 8px 14px; background: var(--bg2);
  border-bottom: 1px solid var(--border); flex-shrink: 0;
}
.panel-label {
  font-size: 0.68rem; font-weight: 600; color: var(--text3);
  text-transform: uppercase; letter-spacing: 0.08em;
  display: flex; align-items: center; gap: 6px;
}
.panel-label .icon { font-size: 0.78rem; }

.code-editor { flex: 1; display: flex; overflow: hidden; background: var(--editor-bg); }

.line-numbers {
  padding: 14px 0; width: 42px; text-align: right; padding-right: 10px;
  font-family: var(--mono); font-size: 0.7rem; color: var(--text3);
  line-height: 1.65; user-select: none;
  border-right: 1px solid var(--border);
  overflow: hidden; flex-shrink: 0; background: rgba(0,0,0,0.15);
}

.code-textarea {
  flex: 1; resize: none; border: none; outline: none;
  background: transparent; color: var(--text);
  font-family: var(--mono); font-size: 0.8rem;
  line-height: 1.65; padding: 14px 16px;
  tab-size: 2; -moz-tab-size: 2; white-space: pre; overflow: auto;
  caret-color: var(--cyan);
}
.code-textarea::placeholder { color: var(--text3); }
.code-textarea:focus { background: rgba(0,210,255,0.01); }

.console-body {
  flex: 1; overflow-y: auto; padding: 14px 16px;
  font-family: var(--mono); font-size: 0.76rem;
  background: var(--editor-bg);
}
.console-welcome {
  color: var(--text3); font-size: 0.72rem; line-height: 1.65;
}
.console-welcome kbd {
  background: var(--surface2); border: 1px solid var(--border2);
  padding: 1px 5px; border-radius: 3px; font-family: var(--mono);
  font-size: 0.62rem; color: var(--text3);
}

.console-line {
  padding: 3px 0; line-height: 1.5;
  border-bottom: 1px solid rgba(255,255,255,0.02);
  display: flex; align-items: flex-start; gap: 8px;
  animation: consoleFadeIn 0.15s var(--ease);
}
@keyframes consoleFadeIn {
  from { opacity:0; transform:translateY(3px); }
  to   { opacity:1; transform:translateY(0); }
}
.console-line .prefix { flex-shrink: 0; font-size: 0.65rem; opacity: 0.4; }
.console-line.log { color: var(--text); }
.console-line.error { color: var(--red); background: var(--red-bg); margin: 2px -16px; padding: 4px 16px; border-radius: 4px; }
.console-line.warn { color: var(--yellow); }
.console-line.success { color: var(--green); }
.console-line.info { color: var(--cyan); }


/* ═══════════════════════════════════════════════════
   TAB: PENSE-BÊTES — Notes
   ═══════════════════════════════════════════════════ */
.notes-filters {
  display: flex; gap: 6px; margin-bottom: 16px; flex-wrap: wrap;
}
.filter-btn {
  font-family: var(--font); font-size: 0.7rem; font-weight: 600;
  padding: 6px 14px; border-radius: 99px;
  border: 1px solid var(--border2); background: transparent;
  color: var(--text3); cursor: pointer; transition: all 0.2s var(--ease);
}
.filter-btn:hover { color: var(--text2); background: var(--surface2); }
.filter-btn.active { color: var(--cyan); background: var(--cyan-bg); border-color: rgba(0,210,255,0.2); }

.notes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 14px;
}

.note-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 16px;
  transition: all 0.25s var(--ease); position: relative;
}
.note-card:hover {
  border-color: var(--border2);
  box-shadow: 0 4px 20px rgba(0,0,0,0.3);
  transform: translateY(-2px);
}
.note-card.important { border-left: 3px solid var(--yellow); }

.note-card-header { display: flex; align-items: flex-start; justify-content: space-between; margin-bottom: 8px; }
.note-title { font-size: 0.88rem; font-weight: 600; color: var(--text); }
.note-star { font-size: 0.8rem; }
.note-category-badge {
  font-size: 0.56rem; font-weight: 700; padding: 2px 7px;
  border-radius: 99px; background: var(--surface2); color: var(--text3);
  margin-bottom: 8px; display: inline-block;
}

.note-content { font-size: 0.78rem; color: var(--text2); line-height: 1.55; margin-bottom: 10px; }

.note-code {
  background: var(--editor-bg); border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 10px 12px;
  font-family: var(--mono); font-size: 0.7rem; color: var(--cyan);
  line-height: 1.5; overflow-x: auto; white-space: pre; margin-bottom: 10px;
}

.note-footer {
  display: flex; align-items: center; justify-content: space-between;
  padding-top: 8px; border-top: 1px solid var(--border);
}
.note-date { font-size: 0.62rem; color: var(--text3); }
.note-actions { display: flex; gap: 6px; }
.note-action-btn {
  font-family: var(--font); font-size: 0.62rem; font-weight: 600;
  padding: 3px 8px; border-radius: var(--radius-sm);
  border: 1px solid var(--border); background: transparent;
  color: var(--text3); cursor: pointer; transition: all 0.15s var(--ease);
}
.note-action-btn:hover { color: var(--text2); background: var(--surface2); }
.note-action-btn.delete:hover { color: var(--red); border-color: rgba(255,71,87,0.3); }

.empty-state {
  grid-column: 1 / -1; text-align: center; padding: 60px 20px;
  color: var(--text3);
}
.empty-icon { font-size: 2.5rem; display: block; margin-bottom: 12px; opacity: 0.5; }
.empty-state p { font-size: 0.88rem; }
.empty-sub { font-size: 0.76rem; margin-top: 4px; color: var(--text3); }


/* ═══════════════════════════════════════════════════
   TAB: TENSORFLOW.JS
   ═══════════════════════════════════════════════════ */
.tf-status {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 0.74rem; color: var(--text3); margin-bottom: 20px;
  padding: 6px 14px; border-radius: 99px;
  background: var(--surface); border: 1px solid var(--border);
}
.tf-status .status-dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--red); flex-shrink: 0;
}
.tf-status.loaded .status-dot { background: var(--green); box-shadow: 0 0 8px rgba(0,255,136,0.4); }
.tf-status.loaded { color: var(--green); border-color: rgba(0,255,136,0.15); }

.tf-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 16px;
}

.tf-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); overflow: hidden;
  transition: all 0.25s var(--ease);
}
.tf-card:hover { border-color: var(--border2); box-shadow: 0 4px 20px rgba(0,0,0,0.3); }

.tf-card-header {
  padding: 16px 18px; display: flex; align-items: center; gap: 10px;
  border-bottom: 1px solid var(--border);
}
.tf-card-icon { font-size: 1.3rem; }
.tf-card-title { font-size: 0.88rem; font-weight: 600; color: var(--text); }
.tf-card-badge {
  margin-left: auto; font-size: 0.56rem; font-weight: 700;
  padding: 2px 8px; border-radius: 99px;
  background: rgba(255,107,53,0.1); color: var(--tf-color);
  border: 1px solid rgba(255,107,53,0.12);
  text-transform: uppercase; letter-spacing: 0.05em;
}

.tf-card-body { padding: 16px 18px; }
.tf-card-desc { font-size: 0.78rem; color: var(--text2); line-height: 1.55; margin-bottom: 12px; }

.tf-card-code {
  background: var(--editor-bg); border: 1px solid var(--border);
  border-radius: var(--radius-sm); padding: 12px 14px;
  font-family: var(--mono); font-size: 0.7rem; color: var(--text);
  line-height: 1.55; overflow-x: auto; white-space: pre;
}

.tf-card-footer {
  padding: 10px 18px; border-top: 1px solid var(--border);
  display: flex; gap: 8px;
}


/* ═══════════════════════════════════════════════════
   MODAL
   ═══════════════════════════════════════════════════ */
.modal-overlay {
  display: none; position: fixed; inset: 0; z-index: 200;
  background: rgba(0,0,0,0.65);
  backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
  justify-content: center; align-items: center; padding: 20px;
}
.modal-overlay.open { display: flex; }

.modal {
  background: var(--bg3); border: 1px solid var(--border2);
  border-radius: var(--radius-xl); width: 100%; max-width: 560px;
  max-height: 90vh; overflow-y: auto;
  box-shadow: 0 20px 60px rgba(0,0,0,0.5);
  animation: modalIn 0.25s var(--ease);
}
@keyframes modalIn {
  from { opacity: 0; transform: translateY(20px) scale(0.96); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.modal-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 18px 24px; border-bottom: 1px solid var(--border);
}
.modal-header h2 {
  font-size: 1.05rem; font-weight: 700;
  background: linear-gradient(135deg, #fff 60%, var(--cyan-dim));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.modal-close {
  background: none; border: 1px solid var(--border); color: var(--text2);
  font-size: 1rem; padding: 4px 10px; border-radius: var(--radius-sm);
  cursor: pointer; transition: all 0.2s var(--ease);
}
.modal-close:hover { color: var(--text); border-color: var(--border2); }

.modal-body { padding: 20px 24px; }

.form-group { margin-bottom: 14px; }
.form-group label {
  display: block; font-size: 0.72rem; font-weight: 600;
  color: var(--text2); margin-bottom: 5px;
}
.label-hint { font-weight: 400; color: var(--text3); }

.form-input {
  width: 100%; padding: 9px 14px;
  background: var(--surface2); border: 1px solid var(--border2);
  border-radius: var(--radius-md); color: var(--text);
  font-family: var(--font); font-size: 0.8rem;
  outline: none; transition: all 0.2s var(--ease);
  resize: vertical;
}
.form-input::placeholder { color: var(--text3); }
.form-input:focus {
  border-color: rgba(0,210,255,0.35);
  box-shadow: 0 0 0 2px rgba(0,210,255,0.08);
}
.form-code { font-family: var(--mono); font-size: 0.76rem; }

select.form-input {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='rgba(255,255,255,0.35)' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 12px center;
  padding-right: 36px;
}
select.form-input option { background: var(--bg3); color: var(--text); }

.form-checkbox {
  display: flex; align-items: center; gap: 8px;
  font-size: 0.78rem; color: var(--text2); cursor: pointer;
  margin-top: 8px;
}
.form-checkbox input[type="checkbox"] {
  accent-color: var(--cyan); width: 16px; height: 16px;
}

.modal-footer {
  display: flex; justify-content: flex-end; gap: 10px;
  padding: 14px 24px; border-top: 1px solid var(--border);
}


/* ═══════════════════════════════════════════════════
   MOBILE OVERLAY & FAB
   ═══════════════════════════════════════════════════ */
.sidebar-overlay {
  display: none; position: fixed; inset: 0; z-index: 149;
  background: rgba(0,0,0,0.6);
  backdrop-filter: blur(4px); -webkit-backdrop-filter: blur(4px);
}
.sidebar-overlay.open { display: block; }

.mobile-fab {
  display: none; position: fixed; z-index: 120;
  bottom: 20px; left: 16px;
  background: var(--cyan); color: #000; border: none;
  border-radius: 99px; padding: 10px 18px;
  font-family: var(--font); font-size: 0.76rem; font-weight: 700;
  cursor: pointer;
  box-shadow: 0 4px 24px var(--cyan-glow), 0 0 0 1px rgba(0,210,255,0.2);
  transition: all 0.25s var(--ease);
}
.mobile-fab:hover {
  box-shadow: 0 6px 32px rgba(0,210,255,0.35);
  transform: translateY(-2px);
}


/* ═══════════════════════════════════════════════════
   RESPONSIVE — TABLETTE ≤1024px
   ═══════════════════════════════════════════════════ */
@media (max-width: 1024px) {
  :root { --sidebar-w: 230px; }
  .topbar { padding: 0 16px; }
  .topbar-nav { gap: 2px; }
  .topbar-link { font-size: 0.7rem; padding: 5px 8px; }
  .tab-content { padding: 16px 18px 40px; }
  .editor-split { grid-template-columns: 1fr; }
  .editor-panel { border-right: none; border-bottom: 1px solid var(--border); min-height: 280px; }
  .console-panel { min-height: 200px; }
}


/* ═══════════════════════════════════════════════════
   RESPONSIVE — MOBILE ≤768px
   ═══════════════════════════════════════════════════ */
@media (max-width: 768px) {
  :root { --topbar-h: 46px; }

  .topbar { padding: 0 12px; }
  .topbar-logo { font-size: 0.9rem; gap: 6px; }
  .topbar-logo-text { display: none; }
  .topbar-sep { display: none; }
  .topbar-page { font-size: 0.66rem; padding: 2px 8px; }
  .topbar-nav { display: none; }
  .back-link { display: none; }
  .mobile-menu-btn { display: flex; }

  .page-layout { grid-template-columns: 1fr; }

  /* Sidebar → overlay */
  .sidebar {
    position: fixed; top: 0; left: 0;
    width: 82vw; max-width: 320px;
    height: 100vh; height: 100dvh;
    z-index: 150;
    transform: translateX(-100%);
    transition: transform 0.3s var(--ease);
    padding-top: 0;
    border-right: 1px solid var(--border2);
    box-shadow: 4px 0 30px rgba(0,0,0,0.4);
  }
  .sidebar.mobile-open { transform: translateX(0); }
  .sidebar-mobile-header { display: flex; }

  .mobile-fab { display: block; }

  /* Tabs compact */
  .tabs-bar { padding: 6px 12px 0; gap: 0; }
  .tab { font-size: 0.68rem; padding: 8px 10px; gap: 4px; }
  .tab-icon { font-size: 0.75rem; }
  .tab-label { display: none; }

  /* Content compact */
  .tab-content { padding: 14px 14px 30px; }
  .content-header { flex-direction: column; gap: 10px; }
  .page-title { font-size: 1.15rem; }

  /* Editor stacked */
  .editor-split { grid-template-columns: 1fr; border-radius: var(--radius-md); }
  .editor-panel { min-height: 220px; border-right: none; border-bottom: 1px solid var(--border); }
  .console-panel { min-height: 160px; }
  .line-numbers { width: 30px; font-size: 0.62rem; padding-right: 6px; }
  .code-textarea { font-size: 0.74rem; padding: 10px 12px; }
  .console-body { font-size: 0.72rem; padding: 10px 12px; }

  /* Notes */
  .notes-grid { grid-template-columns: 1fr; }
  .tf-grid { grid-template-columns: 1fr; }
}


/* ═══════════════════════════════════════════════════
   RESPONSIVE — PETIT MOBILE ≤480px
   ═══════════════════════════════════════════════════ */
@media (max-width: 480px) {
  .topbar { padding: 0 8px; }
  .topbar-page { font-size: 0.62rem; }

  .tabs-bar { padding: 4px 8px 0; overflow-x: auto; }
  .tab { font-size: 0.64rem; padding: 7px 8px; }

  .tab-content { padding: 10px 10px 30px; }
  .page-title { font-size: 1rem; }
  .page-subtitle { font-size: 0.72rem; }

  .btn-primary { font-size: 0.68rem; padding: 7px 14px; }
  .btn-secondary { font-size: 0.68rem; padding: 7px 14px; }

  .lesson-header { padding: 12px 14px; }
  .lesson-title { font-size: 0.84rem; }
  .lesson-body { padding: 0 14px 14px; }

  .code-textarea { font-size: 0.7rem; padding: 8px; }
  .line-numbers { width: 26px; font-size: 0.58rem; }

  .mobile-fab { bottom: 14px; left: 10px; font-size: 0.72rem; padding: 8px 14px; }
  .sidebar { width: 90vw; }

  .modal { border-radius: var(--radius-lg); }
  .modal-header { padding: 14px 18px; }
  .modal-body { padding: 14px 18px; }
  .modal-footer { padding: 10px 18px; }
}


/* ═══════════════════════════════════════════════════
   LANDSCAPE MOBILE
   ═══════════════════════════════════════════════════ */
@media (max-height: 500px) and (orientation: landscape) {
  :root { --topbar-h: 36px; }
  .tabs-bar { padding: 4px 12px 0; }
  .tab { padding: 6px 10px; font-size: 0.66rem; }
  .tab-content { padding: 10px 14px 20px; }
  .page-title { font-size: 1rem; }
  .page-subtitle { display: none; }
}