/* ==========================================================================
   TIN12 HUB - Design System: Neumorphism + Glassmorphism
   Tối ưu Mobile-First, Chuẩn Công thái học Thumb Zone & WCAG 2.1 AA
   ========================================================================== */

:root {
  /* Bảng màu Pastel - Light Mode */
  --bg-app: #f0f4f9;
  --bg-card: rgba(255, 255, 255, 0.72);
  --bg-card-solid: #ffffff;
  --text-main: #1e293b;
  --text-muted: #64748b;
  --text-dim: #94a3b8;
  
  /* Điểm nhấn thương hiệu */
  --accent-blue: #0284c7;
  --accent-blue-light: #e0f2fe;
  --accent-salmon: #f43f5e;
  --accent-salmon-light: #ffe4e6;
  --accent-mint: #10b981;
  --accent-amber: #f59e0b;

  /* Hiệu ứng Kính Mờ (Glassmorphism) */
  --glass-bg: rgba(255, 255, 255, 0.75);
  --glass-border: rgba(255, 255, 255, 0.85);
  --glass-card-shadow: 0 10px 30px -5px rgba(0, 0, 0, 0.05), 0 4px 10px -2px rgba(0, 0, 0, 0.02);

  /* Hiệu ứng Nổi/Lõm (Neumorphism Dual Shadows) */
  --neu-shadow-raised: 8px 8px 18px #d9e0ea, -8px -8px 18px #ffffff;
  --neu-shadow-raised-sm: 4px 4px 10px #d9e0ea, -4px -4px 10px #ffffff;
  --neu-shadow-inset: inset 4px 4px 8px #d9e0ea, inset -4px -4px 8px #ffffff;
  --neu-border: 1px solid rgba(255, 255, 255, 0.6);

  /* Typography chuẩn - Fluid Responsive Typography System (Mobile-First & High Visibility) */
  --font-base: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --body-size: clamp(16.5px, 0.65vw + 14.5px, 20px);
  --body-line-height: 1.68;
  --heading-xl: clamp(1.95rem, 3.2vw + 1.15rem, 3.4rem);
  --heading-lg: clamp(1.55rem, 2.4vw + 0.95rem, 2.7rem);
  --heading-md: clamp(1.28rem, 1.6vw + 0.85rem, 2.05rem);
  --heading-sm: clamp(1.1rem, 1.1vw + 0.75rem, 1.55rem);
}

/* ==========================================================================
   Dark Mode Cấu hình chuẩn (#212121)
   ========================================================================== */
.dark {
  --bg-app: #212121;
  --bg-card: rgba(38, 38, 38, 0.78);
  --bg-card-solid: #262626;
  --text-main: #f1f5f9;
  --text-muted: #cbd5e1;
  --text-dim: #64748b;

  --accent-blue: #38bdf8;
  --accent-blue-light: rgba(56, 189, 248, 0.15);
  --accent-salmon: #fb7185;
  --accent-salmon-light: rgba(251, 113, 133, 0.15);

  --glass-bg: rgba(33, 33, 33, 0.82);
  --glass-border: rgba(255, 255, 255, 0.08);
  --glass-card-shadow: 0 10px 30px -5px rgba(0, 0, 0, 0.5), 0 0 1px 1px rgba(255, 255, 255, 0.05);

  --neu-shadow-raised: 6px 6px 16px #161616, -6px -6px 16px #2c2c2c;
  --neu-shadow-raised-sm: 3px 3px 8px #161616, -3px -3px 8px #2c2c2c;
  --neu-shadow-inset: inset 3px 3px 6px #141414, inset -3px -3px 6px #2e2e2e;
  --neu-border: 1px solid rgba(255, 255, 255, 0.08);
}

/* ==========================================================================
   Cài đặt Nền tảng & Typography
   ========================================================================== */
html {
  font-family: var(--font-base);
  font-size: var(--body-size);
  line-height: var(--body-line-height);
  color: var(--text-main);
  background-color: var(--bg-app);
  scroll-behavior: smooth;
  -webkit-tap-highlight-color: transparent;
}

h1 { font-size: var(--heading-xl); line-height: 1.25; font-weight: 800; letter-spacing: -0.025em; }
h2 { font-size: var(--heading-lg); line-height: 1.3; font-weight: 800; letter-spacing: -0.02em; }
h3 { font-size: var(--heading-md); line-height: 1.35; font-weight: 700; letter-spacing: -0.015em; }
h4 { font-size: var(--heading-sm); line-height: 1.4; font-weight: 700; }
p { line-height: var(--body-line-height); }

body {
  margin: 0;
  padding: 0;
  min-height: 100vh;
  background-color: var(--bg-app);
  transition: background-color 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
  padding-bottom: 84px; /* Chừa không gian cho Mobile Bottom Nav */
}

@media (min-width: 768px) {
  body {
    padding-bottom: 0;
    padding-left: 0; /* Mặc định tràn viền 100% cho Tivi & Màn hình lớn */
    transition: padding-left 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  }

  body.sidebar-pinned {
    padding-left: 280px; /* Khi giáo viên bấm nút Ghim Menu */
  }
}

/* ==========================================================================
   Thành phần Neumorphic (Dual Shadows & Pressed State)
   ========================================================================== */
.neu-box {
  background: var(--bg-app);
  box-shadow: var(--neu-shadow-raised);
  border-radius: 20px;
  border: var(--neu-border);
  transition: all 0.25s ease;
}

.neu-box-sm {
  background: var(--bg-app);
  box-shadow: var(--neu-shadow-raised-sm);
  border-radius: 14px;
  border: var(--neu-border);
}

.neu-box-inset {
  background: var(--bg-app);
  box-shadow: var(--neu-shadow-inset);
  border-radius: 16px;
  border: var(--neu-border);
}

/* Touch Targets: Nút bấm tối thiểu 44x44px */
.btn-touch {
  min-height: 44px;
  min-width: 44px;
  padding: 10px 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
  font-weight: 600;
  border-radius: 14px;
  cursor: pointer;
  user-select: none;
  border: none;
  outline: none;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: var(--neu-shadow-raised-sm);
  background: var(--bg-app);
  color: var(--text-main);
  text-decoration: none;
}

.btn-touch:active {
  box-shadow: var(--neu-shadow-inset) !important;
  transform: scale(0.98);
}

/* Biến thể nút nổi bật */
.btn-primary {
  background: linear-gradient(135deg, var(--accent-blue), #0284c7);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(2, 132, 199, 0.35);
}

.btn-primary:active {
  box-shadow: inset 0 3px 6px rgba(0, 0, 0, 0.2) !important;
}

.btn-salmon {
  background: linear-gradient(135deg, var(--accent-salmon), #e11d48);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(244, 63, 94, 0.35);
}

/* ==========================================================================
   Thành phần Kính Mờ (Glassmorphism)
   ========================================================================== */
.glass-panel {
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-card-shadow);
  border-radius: 20px;
}

.glass-bottom-nav {
  position: fixed;
  bottom: 12px;
  left: 12px;
  right: 12px;
  height: 64px;
  background: var(--glass-bg);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border: 1px solid var(--glass-border);
  box-shadow: 0 12px 36px rgba(0, 0, 0, 0.15);
  border-radius: 32px;
  display: flex;
  align-items: center;
  justify-content: space-around;
  z-index: 1000;
  padding: 0 8px;
}

@media (min-width: 768px) {
  .glass-bottom-nav {
    display: none; /* Ẩn trên Desktop, dùng Sidebar */
  }
}

/* Desktop Sidebar - Tự động Ẩn/Hiện khi rê chuột (Hover-to-Reveal) */
.desktop-sidebar,
.sidebar-hover-zone,
.sidebar-peek-tab {
  display: none;
}

@media (min-width: 768px) {
  .desktop-sidebar {
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: 280px;
    background: var(--glass-bg);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border-right: 1px solid var(--glass-border);
    padding: 24px 16px;
    z-index: 990;
    box-shadow: 10px 0 35px rgba(0, 0, 0, 0.12);
    overflow-y: auto;
    transform: translateX(-100%);
    transition: transform 0.28s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.28s ease;
  }

  /* Trượt ra khi rê chuột vào thanh hoặc khi được kích hoạt */
  .desktop-sidebar:hover,
  .desktop-sidebar.is-hovered,
  body.sidebar-pinned .desktop-sidebar {
    transform: translateX(0);
    box-shadow: 12px 0 40px rgba(0, 0, 0, 0.2);
  }

  /* Vùng cảm biến rê chuột 20px ở mép trái màn hình */
  .sidebar-hover-zone {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: 22px;
    z-index: 980;
    cursor: pointer;
  }

  /* Nút thẻ tab nhỏ bám mép trái báo hiệu vị trí Menu */
  .sidebar-peek-tab {
    position: fixed;
    top: 48%;
    left: 0;
    transform: translateY(-50%);
    z-index: 985;
    background: var(--accent-blue);
    color: #ffffff;
    padding: 12px 6px;
    border-radius: 0 12px 12px 0;
    box-shadow: 3px 0 14px rgba(2, 132, 199, 0.35);
    cursor: pointer;
    font-size: 11px;
    font-weight: 700;
    writing-mode: vertical-rl;
    text-orientation: mixed;
    letter-spacing: 1.5px;
    transition: all 0.2s ease;
    user-select: none;
    display: flex;
    align-items: center;
    gap: 6px;
  }

  .sidebar-peek-tab:hover {
    padding-left: 10px;
    background: #0284c7;
    transform: translateY(-50%) scale(1.05);
  }

  body.sidebar-pinned .sidebar-peek-tab {
    display: none !important;
  }
}

/* Navigation Item */
.nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-width: 52px;
  min-height: 48px;
  color: var(--text-muted);
  border-radius: 16px;
  font-size: 11px;
  font-weight: 500;
  text-decoration: none;
  transition: all 0.2s ease;
  position: relative;
}

.nav-item.active {
  color: var(--accent-blue);
  font-weight: 700;
}

.nav-item.active::after {
  content: '';
  position: absolute;
  bottom: 4px;
  width: 16px;
  height: 3px;
  background: var(--accent-blue);
  border-radius: 2px;
}

@media (min-width: 768px) {
  .desktop-nav-item {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 14px;
    padding: 12px 16px;
    border-radius: 14px;
    color: var(--text-muted);
    font-size: 15px;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.2s;
    margin-bottom: 6px;
  }

  .desktop-nav-item:hover {
    background: var(--accent-blue-light);
    color: var(--accent-blue);
  }

  .desktop-nav-item.active {
    background: var(--accent-blue);
    color: #ffffff;
    box-shadow: 0 4px 14px rgba(2, 132, 199, 0.3);
  }
}

@media (min-width: 1024px) {
  .desktop-sidebar {
    width: 350px;
    padding: 24px 18px;
  }

  body.sidebar-pinned {
    padding-left: 350px;
  }

  .sidebar-brand-title {
    font-size: 1.25rem !important;
    line-height: 1.2 !important;
    white-space: nowrap !important;
  }

  .sidebar-brand-sub {
    font-size: 0.85rem !important;
    white-space: nowrap !important;
  }

  .desktop-nav-item {
    font-size: 1.05rem !important;
    padding: 13px 16px !important;
  }

  .desktop-nav-item i {
    width: 20px !important;
    height: 20px !important;
  }
}

/* ==========================================================================
   Mobile-First Layout Stacking (1 Cột)
   ========================================================================== */
.content-stack {
  display: flex;
  flex-direction: column;
  width: 100%;
  gap: 20px;
}

@media (min-width: 1024px) {
  .content-grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }
  .content-grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
  }
}

/* ==========================================================================
   Thanh công cụ Ký tự đặc biệt (Floating Mobile Code Toolbar)
   ========================================================================== */
.code-toolbar {
  display: flex;
  overflow-x: auto;
  gap: 8px;
  padding: 8px 12px;
  background: var(--bg-card-solid);
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  scrollbar-width: none;
}
.code-toolbar::-webkit-scrollbar {
  display: none;
}

.key-chip {
  flex-shrink: 0;
  min-height: 38px;
  min-width: 38px;
  padding: 0 10px;
  font-family: 'Courier New', Courier, monospace;
  font-weight: bold;
  font-size: 14px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-app);
  border: var(--neu-border);
  border-radius: 8px;
  box-shadow: var(--neu-shadow-raised-sm);
  cursor: pointer;
  user-select: none;
}

.key-chip:active {
  box-shadow: var(--neu-shadow-inset);
  transform: translateY(1px);
}

/* ==========================================================================
   Interactive Code Playground Styling
   ========================================================================== */
.code-editor-area {
  font-family: 'Consolas', 'Fira Code', 'Courier New', monospace;
  font-size: 14px;
  line-height: 1.5;
  border: none;
  outline: none;
  resize: none;
  background: transparent;
  color: var(--text-main);
  width: 100%;
}

.preview-frame {
  width: 100%;
  height: 320px;
  border: 1px solid var(--glass-border);
  border-radius: 14px;
  background: #ffffff;
}

/* ==========================================================================
   Toast Notification & Dialogs
   ========================================================================== */
.toast-msg {
  position: fixed;
  top: 20px;
  left: 50%;
  transform: translateX(-50%) translateY(-100px);
  background: var(--text-main);
  color: var(--bg-app);
  padding: 12px 24px;
  border-radius: 30px;
  font-size: 14px;
  font-weight: 600;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
  z-index: 2000;
  opacity: 0;
  pointer-events: none;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  align-items: center;
  gap: 8px;
}

.toast-msg.show {
  transform: translateX(-50%) translateY(0);
  opacity: 1;
}

/* Trạng thái Accordion */
.accordion-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease-out;
}

.accordion-item.open .accordion-content {
  max-height: 1200px;
}

.accordion-item.open .chevron-icon {
  transform: rotate(180deg);
}

/* ==========================================================================
   Thẻ Flashcard Active Recall 3D Lật Thẻ
   ========================================================================== */
.flashcard-box {
  perspective: 1000px;
  cursor: pointer;
  user-select: none;
}

.flashcard-inner {
  position: relative;
  width: 100%;
  height: 140px;
  text-align: center;
  transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  transform-style: preserve-3d;
}

.flashcard-box.flipped .flashcard-inner {
  transform: rotateY(180deg);
}

.flashcard-front, .flashcard-back {
  position: absolute;
  width: 100%;
  height: 100%;
  -webkit-backface-visibility: hidden;
  backface-visibility: hidden;
  border-radius: 16px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 16px;
  box-shadow: var(--neu-shadow-raised-sm);
  background: var(--bg-card);
  border: var(--neu-border);
}

.flashcard-back {
  transform: rotateY(180deg);
  background: var(--accent-blue-light);
  border-color: var(--accent-blue);
}

.dark .flashcard-back {
  background: rgba(56, 189, 248, 0.1);
}

/* ==========================================================================
   Interactive Micro-Quiz Options Styling
   ========================================================================== */
.quiz-opt-btn {
  width: 100%;
  text-align: left;
  padding: 12px 16px;
  border-radius: 14px;
  min-height: 48px;
  background: var(--bg-app);
  box-shadow: var(--neu-shadow-raised-sm);
  border: 1px solid transparent;
  color: var(--text-main);
  font-size: 13px;
  cursor: pointer;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.quiz-opt-btn:active {
  box-shadow: var(--neu-shadow-inset);
  transform: scale(0.99);
}

.quiz-opt-btn.correct {
  background: #ecfdf5 !important;
  border-color: #10b981 !important;
  color: #065f46 !important;
  box-shadow: 0 0 0 2px #10b981 !important;
}

.dark .quiz-opt-btn.correct {
  background: #064e3b !important;
  color: #a7f3d0 !important;
}

.quiz-opt-btn.wrong {
  background: #fff1f2 !important;
  border-color: #f43f5e !important;
  color: #9f1239 !important;
  box-shadow: 0 0 0 2px #f43f5e !important;
}

.dark .quiz-opt-btn.wrong {
  background: #881337 !important;
  color: #fecdd3 !important;
}

/* ==========================================================================
   3-Tier Scaffolding Code Tabs (Core / Challenge / Pro)
   ========================================================================== */
.tier-tab-btn {
  padding: 8px 14px;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 700;
  transition: all 0.2s ease;
  cursor: pointer;
  border: 1px solid transparent;
  min-height: 38px;
}

.tier-tab-btn.active {
  background: var(--accent-blue);
  color: #ffffff;
  box-shadow: var(--neu-shadow-raised-sm);
}

.tier-tab-btn.active.tier-challenge {
  background: var(--accent-amber);
  color: #ffffff;
}

.tier-tab-btn.active.tier-pro {
  background: var(--accent-salmon);
  color: #ffffff;
}

/* ==========================================================================
   Visual Tag Anatomy Component (Giải phẫu cú pháp trực quan)
   ========================================================================== */
.tag-anatomy-container {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  background: rgba(15, 23, 42, 0.04);
  border-radius: 14px;
  border: 1.5px dashed rgba(148, 163, 184, 0.4);
  font-family: 'Fira Code', 'Consolas', monospace;
  font-size: clamp(13px, 0.35vw + 11px, 16px);
}

.dark .tag-anatomy-container {
  background: rgba(0, 0, 0, 0.3);
  border-color: rgba(255, 255, 255, 0.15);
}

.anatomy-pill {
  padding: 6px 12px;
  border-radius: 10px;
  font-weight: 700;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  line-height: 1.25;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.06);
  border: 1px solid rgba(0, 0, 0, 0.06);
  font-size: clamp(13px, 0.35vw + 11px, 16px);
}

.dark .anatomy-pill {
  border-color: rgba(255, 255, 255, 0.12);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.anatomy-sub {
  font-size: clamp(10px, 0.25vw + 8.5px, 12px);
  opacity: 0.85;
  font-family: var(--font-base);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin-top: 2px;
}

/* ==========================================================================
   Flashcards Spaced Repetition Mastery Tracker
   ========================================================================== */
.mastery-btn {
  min-height: 34px;
  padding: 6px 12px;
  border-radius: 10px;
  font-size: 11px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.mastery-btn:active {
  transform: scale(0.96);
}

/* ==========================================================================
   Digital Learning Passport Modal (Phiếu Học Tập Số)
   ========================================================================== */
.passport-modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 100;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
}

.passport-card {
  max-width: 480px;
  width: 100%;
  background: var(--bg-app);
  border-radius: 24px;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.35);
  border: 2px solid rgba(56, 189, 248, 0.3);
  overflow: hidden;
  animation: modalPop 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes modalPop {
  0% { transform: scale(0.9); opacity: 0; }
  100% { transform: scale(1); opacity: 1; }
}

/* ==========================================================================
   Kiến Trúc Typography Đa Thiết Bị: Chống Chữ Li Ti & Tối Ưu Tầm Nhìn Xa
   (Khoa học, tinh tế, dễ đọc từ cuối lớp học 6-8m)
   ========================================================================== */

/* 1. Universal Anti-Micro-Font Architecture: Loại bỏ hoàn toàn chữ nhỏ dưới 13px */
.text-\[9px\], [class*="text-[9px]"],
.text-\[10px\], [class*="text-[10px]"] {
  font-size: 13px !important;
  line-height: 1.5 !important;
}

.text-\[11px\], [class*="text-[11px]"] {
  font-size: 14px !important;
  line-height: 1.55 !important;
}

.text-xs {
  font-size: 15px !important;
  line-height: 1.6 !important;
}

.text-sm {
  font-size: 16.5px !important;
  line-height: 1.62 !important;
}

.text-base {
  font-size: 18px !important;
  line-height: 1.65 !important;
}

/* ==========================================================================
   HỆ THỐNG THÍCH ỨNG THÔNG MINH THEO THIẾT BỊ (INTELLIGENT DEVICE ADAPTER)
   - Tự động nhận diện thiết bị & độ phân giải màn hình không cần nút bấm chọn
   - Mặc định: Laptop, Máy tính để bàn, Tivi -> TỰ ĐỘNG LÀ CHẾ ĐỘ TIVI 60 INCH
   - iPad / Tablet: Tự động tối ưu giao diện máy tính bảng 18px - 21px
   - Mobile: Tự động tối ưu giao diện di động 1 cột 16px - 17.5px, Bottom Nav
   - Tự động co giãn mượt mà khi zoom in/out hoặc thay đổi kích thước cửa sổ
   ========================================================================== */

/* 1. Môi trường iPad & Máy Tính Bảng (768px đến 1023.98px) */
@media (min-width: 768px) and (max-width: 1023.98px) {
  :root, html.device-tablet {
    --body-size: clamp(18px, 1.2vw + 10px, 21px);
    font-size: clamp(18px, 1.2vw + 10px, 21px);
  }

  main {
    max-width: 94vw !important;
    width: 94vw !important;
    padding-left: 20px !important;
    padding-right: 20px !important;
  }

  .btn-touch {
    min-height: 48px !important;
    font-size: 16px !important;
    padding: 12px 20px !important;
    border-radius: 16px !important;
  }

  pre, code, textarea.code-editor-area, .cloze-code-snippet {
    font-size: 16px !important;
    line-height: 1.75 !important;
  }
}

/* 2. Môi trường Laptop, Máy Tính & Tivi 60" (>= 1024px)
   => MẶC ĐỊNH TỰ ĐỘNG KÍCH HOẠT CHẾ ĐỘ TIVI 60 INCH VỚI TỶ LỆ CHUẨN SƯ PHẠM */
@media (min-width: 1024px) {
  :root {
    --body-size: clamp(18px, 0.35vw + 14.5px, 20.5px) !important;
    --body-line-height: 1.62 !important;
  }

  html {
    font-size: clamp(18px, 0.35vw + 14.5px, 20.5px) !important;
  }

  main {
    max-width: clamp(1120px, 86vw, 1460px) !important;
    width: 86vw !important;
    padding-left: 20px !important;
    padding-right: 20px !important;
    margin-left: auto !important;
    margin-right: auto !important;
  }

  h1 {
    font-size: clamp(2.2rem, 1.8vw + 1.2rem, 2.85rem) !important;
    line-height: 1.25 !important;
    letter-spacing: -0.02em !important;
    font-weight: 900 !important;
  }

  h2 {
    font-size: clamp(1.75rem, 1.3vw + 0.95rem, 2.25rem) !important;
    line-height: 1.3 !important;
    letter-spacing: -0.015em !important;
    font-weight: 800 !important;
  }

  h3 {
    font-size: clamp(1.35rem, 1.0vw + 0.75rem, 1.75rem) !important;
    line-height: 1.35 !important;
    font-weight: 800 !important;
  }

  h4 {
    font-size: clamp(1.15rem, 0.75vw + 0.65rem, 1.4rem) !important;
    line-height: 1.4 !important;
    font-weight: 700 !important;
  }

  /* Nút bấm tự động phóng đại siêu êm, công thái học */
  .btn-touch {
    min-height: 48px !important;
    font-size: 0.95rem !important;
    padding: 10px 22px !important;
    font-weight: 700 !important;
    border-radius: 14px !important;
    gap: 8px !important;
  }

  /* Khung Code Lab & Snippet hiển thị sắc nét, vừa vặn không tràn */
  pre, code, textarea.code-editor-area, .cloze-code-snippet {
    font-size: clamp(15px, 0.3vw + 12.5px, 17.5px) !important;
    line-height: 1.75 !important;
    max-height: 580px !important;
    letter-spacing: 0.01em !important;
  }

  .preview-frame {
    min-height: 480px !important;
  }

  .flashcard-box {
    min-height: 200px !important;
  }

  .flashcard-inner {
    height: 200px !important;
    font-size: 1.15rem !important;
  }

  .quiz-opt-btn {
    min-height: 54px !important;
    font-size: 1.05rem !important;
    padding: 12px 20px !important;
  }

  .socratic-bubble {
    font-size: 1.05rem !important;
    line-height: 1.65 !important;
    padding: 16px 20px !important;
  }

  .cloze-choice-btn {
    min-height: 48px !important;
    font-size: 1.05rem !important;
    padding: 10px 20px !important;
  }

  .prompt-builder-pill {
    min-height: 44px !important;
    font-size: 0.95rem !important;
    padding: 8px 16px !important;
  }

  .neu-box, .glass-panel {
    padding: 22px 26px !important;
    border-radius: 20px !important;
  }

  .grid-cols-1.md\:grid-cols-2 {
    grid-template-columns: repeat(auto-fit, minmax(380px, 1fr)) !important;
    gap: 18px !important;
  }

  .grid-cols-1.sm\:grid-cols-2.lg\:grid-cols-4,
  .grid-cols-2.md\:grid-cols-4 {
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)) !important;
    gap: 14px !important;
  }
}

/* Đồng bộ khi JS gắn class tv-mode hoặc device-desktop-tv */
.tv-mode, html.device-desktop-tv {
  --body-size: clamp(18px, 0.35vw + 14.5px, 20.5px) !important;
  --body-line-height: 1.62 !important;
  font-size: clamp(18px, 0.35vw + 14.5px, 20.5px) !important;
}

/* Fluid Responsive Grid khi zoom in/out */
.content-grid-fluid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 20px;
  width: 100%;
}

/* ==========================================================================
   Phòng Triển Lãm Số (Gallery Walk) & Quản Lý Đa Lớp (12C1, 12C2...)
   ========================================================================== */
.class-tab-pill {
  padding: 8px 16px;
  border-radius: 12px;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 1px solid rgba(148, 163, 184, 0.2);
  background: rgba(148, 163, 184, 0.12);
  color: var(--text-muted);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  white-space: nowrap;
}

.class-tab-pill:hover {
  background: var(--accent-blue-light);
  color: var(--accent-blue);
  transform: translateY(-1px);
}

.class-tab-pill.active {
  background: var(--accent-blue);
  color: #ffffff;
  border-color: var(--accent-blue);
  box-shadow: 0 4px 14px rgba(2, 132, 199, 0.35);
}

.badge-pulse {
  animation: badgePulseAnim 2s infinite;
}

@keyframes badgePulseAnim {
  0% { transform: scale(1); box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.7); }
  70% { transform: scale(1.04); box-shadow: 0 0 0 8px rgba(16, 185, 129, 0); }
  100% { transform: scale(1); box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

/* Modal Giả Lập Màn Hình Điện Thoại (Device Mockup Preview) */
.device-modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 1000;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(10px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
}

.device-mockup-frame {
  width: 375px;
  height: 720px;
  max-width: 90vw;
  max-height: 85vh;
  border-radius: 44px;
  border: 10px solid #0f172a;
  box-shadow: 0 25px 60px -15px rgba(0, 0, 0, 0.6), 0 0 0 2px rgba(255, 255, 255, 0.1);
  position: relative;
  overflow: hidden;
  background: #ffffff;
  display: flex;
  flex-direction: column;
  animation: modalPop 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.device-mockup-notch {
  width: 130px;
  height: 22px;
  background: #0f172a;
  border-radius: 0 0 16px 16px;
  margin: 0 auto;
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  z-index: 20;
}

.device-mockup-screen {
  flex: 1;
  width: 100%;
  height: 100%;
  border: none;
  background: #ffffff;
}

/* Modal Chấm Điểm Rubric 360 */
.rubric-score-pill {
  padding: 6px 10px;
  border-radius: 8px;
  font-size: 11px;
  font-weight: 700;
  border: 1px solid rgba(148, 163, 184, 0.3);
  cursor: pointer;
  transition: all 0.15s ease;
  background: rgba(148, 163, 184, 0.1);
  color: var(--text-muted);
}

.rubric-score-pill:hover {
  background: var(--accent-blue-light);
  color: var(--accent-blue);
}

.rubric-score-pill.active {
  background: var(--accent-blue);
  color: #ffffff;
  border-color: var(--accent-blue);
  box-shadow: 0 2px 8px rgba(2, 132, 199, 0.35);
}

/* Bảng nhận xét đánh giá */
.review-item {
  padding: 10px 14px;
  border-radius: 12px;
  background: rgba(148, 163, 184, 0.08);
  border: 1px solid rgba(148, 163, 184, 0.15);
  font-size: 12px;
}

/* ==========================================================================
   Khung Trình Chiếu Video Cinematic & Bộ Chương Tương Tác
   ========================================================================== */
.cinematic-video-frame {
  position: relative;
  width: 100%;
  border-radius: 24px;
  overflow: hidden;
  background: #020617;
  border: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: 0 20px 40px -15px rgba(0, 0, 0, 0.5), 0 0 25px rgba(56, 189, 248, 0.15);
}

.video-poster-box {
  width: 100%;
  aspect-ratio: 16 / 9;
  background: radial-gradient(circle at 50% 40%, #1e293b 0%, #090d16 100%);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  position: relative;
  padding: 24px;
  cursor: pointer;
  user-select: none;
}

.play-pulse-btn {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: linear-gradient(135deg, #0284c7, #38bdf8);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 0 0 rgba(56, 189, 248, 0.7);
  animation: playPulseAnim 2.2s infinite;
  transition: transform 0.25s ease;
}

.play-pulse-btn:hover {
  transform: scale(1.12);
}

@keyframes playPulseAnim {
  0% { box-shadow: 0 0 0 0 rgba(56, 189, 248, 0.7); }
  70% { box-shadow: 0 0 0 22px rgba(56, 189, 248, 0); }
  100% { box-shadow: 0 0 0 0 rgba(56, 189, 248, 0); }
}

.chapter-pill {
  padding: 8px 14px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
  background: rgba(148, 163, 184, 0.12);
  color: var(--text-muted);
  border: 1px solid rgba(148, 163, 184, 0.2);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  white-space: nowrap;
}

.chapter-pill:hover {
  background: var(--accent-blue-light);
  color: var(--accent-blue);
  transform: translateY(-1px);
}

.chapter-pill.active {
  background: var(--accent-blue);
  color: #ffffff;
  border-color: var(--accent-blue);
  box-shadow: 0 4px 12px rgba(2, 132, 199, 0.35);
}

/* ==========================================================================
   Bộ Thẻ Hướng Dẫn Cách Học 4 Bước & Công Cụ Di Động
   ========================================================================== */
.guide-step-card {
  padding: 20px;
  border-radius: 20px;
  background: var(--bg-app);
  box-shadow: var(--neu-shadow-raised-sm);
  border: 1px solid rgba(255, 255, 255, 0.6);
  position: relative;
  transition: all 0.25s ease;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.guide-step-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--neu-shadow-raised);
}

.step-num-badge {
  width: 32px;
  height: 32px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 13px;
}

.toolkit-card {
  padding: 16px;
  border-radius: 16px;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  transition: all 0.2s ease;
}

.toolkit-card:hover {
  border-color: var(--accent-blue);
  transform: translateY(-2px);
}

/* Thống Kê Trang Chủ */
.home-stat-box {
  padding: 16px 12px;
  border-radius: 18px;
  background: var(--glass-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  box-shadow: var(--neu-shadow-raised);
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.home-stat-box:hover {
  transform: translateY(-2px);
  border-color: var(--accent-blue);
}

.home-stat-number {
  font-size: clamp(1.35rem, 1.4vw + 0.6rem, 1.85rem);
  font-weight: 900;
  line-height: 1.25;
  white-space: nowrap;
  letter-spacing: -0.02em;
  margin-bottom: 4px;
}

.home-stat-label {
  font-size: clamp(11.5px, 0.35vw + 9.5px, 13px);
  font-weight: 700;
  line-height: 1.35;
  color: var(--text-muted);
  white-space: normal;
  max-width: 100%;
}

/* ==========================================================================
   Phòng Triển Lãm Số Nâng Cao: Bài Mẫu Giáo Viên & Lọc Theo Bài Học
   ========================================================================== */
.gold-master-card {
  position: relative;
  background: linear-gradient(135deg, rgba(254, 243, 199, 0.45) 0%, var(--bg-card) 60%);
  border: 2px solid #f59e0b !important;
  box-shadow: 0 10px 30px rgba(245, 158, 11, 0.18), var(--neu-shadow-raised) !important;
  overflow: hidden;
}

.gold-master-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, #f59e0b, #ec4899, #38bdf8);
}

.master-badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 4px 10px;
  border-radius: 12px;
  background: linear-gradient(135deg, #f59e0b, #d97706);
  color: #ffffff;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.3px;
  box-shadow: 0 3px 10px rgba(217, 119, 6, 0.35);
}

.lesson-tab-pill {
  padding: 6px 12px;
  border-radius: 10px;
  font-size: 11px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
  background: rgba(148, 163, 184, 0.12);
  color: var(--text-muted);
  border: 1px solid rgba(148, 163, 184, 0.25);
  display: inline-flex;
  align-items: center;
  gap: 4px;
  white-space: nowrap;
}

.lesson-tab-pill:hover {
  background: var(--accent-blue-light);
  color: var(--accent-blue);
  transform: translateY(-1px);
}

.lesson-tab-pill.active {
  background: var(--accent-blue);
  color: #ffffff;
  border-color: var(--accent-blue);
  box-shadow: 0 3px 10px rgba(2, 132, 199, 0.3);
}

.lesson-tab-pill.pill-gold.active {
  background: #d97706;
  border-color: #d97706;
  box-shadow: 0 3px 10px rgba(217, 119, 6, 0.4);
}

.iframe-hint-banner {
  padding: 8px 12px;
  background: #0f172a;
  border-bottom: 1px solid #1e293b;
  font-size: 11px;
  color: #94a3b8;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

/* ==========================================================================
   UPGRADE 1: Socratic AI Pedagogical Code Assistant (Chủ đề 4 - Code Lab)
   ========================================================================== */
.socratic-panel {
  background: var(--bg-card);
  border: 1.5px solid rgba(56, 189, 248, 0.35);
  box-shadow: 0 10px 30px rgba(56, 189, 248, 0.1), var(--neu-shadow-raised);
  border-radius: 20px;
  position: relative;
  overflow: hidden;
}

.socratic-panel::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, #38bdf8, #818cf8, #f43f5e);
}

.socratic-chip {
  min-height: 44px;
  padding: 8px 14px;
  border-radius: 14px;
  font-size: 12px;
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--bg-app);
  box-shadow: var(--neu-shadow-raised-sm);
  border: 1px solid rgba(148, 163, 184, 0.2);
  color: var(--text-main);
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  user-select: none;
}

.socratic-chip:hover {
  transform: translateY(-2px);
  border-color: var(--accent-blue);
  color: var(--accent-blue);
}

.socratic-chip:active {
  box-shadow: var(--neu-shadow-inset);
  transform: scale(0.98);
}

.socratic-bubble {
  border-radius: 16px;
  padding: 14px 16px;
  background: rgba(240, 249, 255, 0.85);
  border: 1px solid rgba(56, 189, 248, 0.4);
  color: #0369a1;
  font-size: 13px;
  line-height: 1.6;
}

.dark .socratic-bubble {
  background: rgba(12, 74, 110, 0.35);
  border-color: rgba(56, 189, 248, 0.3);
  color: #bae6fd;
}

.socratic-step-hint {
  border-radius: 12px;
  background: var(--bg-card);
  border: 1px dashed rgba(56, 189, 248, 0.4);
  padding: 10px 14px;
  margin-top: 8px;
  font-size: 12px;
}

/* ==========================================================================
   UPGRADE 2: Ngân Hàng Đề Thi Khảo Sát Năng Lực 2025 (Bộ GD&ĐT)
   ========================================================================== */
.exam-view-toggle-btn {
  min-height: 44px;
  padding: 10px 18px;
  border-radius: 14px;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.25s ease;
  border: 1.5px solid transparent;
}

.exam-view-toggle-btn.active {
  background: linear-gradient(135deg, #0284c7, #0369a1);
  color: #ffffff !important;
  box-shadow: 0 4px 14px rgba(2, 132, 199, 0.35);
}

.exam-section-header {
  border-left: 4px solid var(--accent-blue);
  padding-left: 12px;
  margin-bottom: 12px;
}

.exam-tf-item {
  border-radius: 14px;
  padding: 12px 14px;
  background: var(--bg-app);
  border: 1px solid rgba(148, 163, 184, 0.2);
  margin-bottom: 10px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

@media (min-width: 640px) {
  .exam-tf-item {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }
}

.tf-choice-group {
  display: flex;
  gap: 8px;
  flex-shrink: 0;
}

.tf-choice-btn {
  min-height: 44px;
  min-width: 72px;
  padding: 8px 12px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 800;
  border: 1.5px solid rgba(148, 163, 184, 0.3);
  background: var(--bg-card);
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.tf-choice-btn:hover {
  border-color: var(--accent-blue);
}

.tf-choice-btn.selected-true {
  background: #10b981 !important;
  color: #ffffff !important;
  border-color: #059669 !important;
  box-shadow: 0 3px 10px rgba(16, 185, 129, 0.35);
}

.tf-choice-btn.selected-false {
  background: #f43f5e !important;
  color: #ffffff !important;
  border-color: #e11d48 !important;
  box-shadow: 0 3px 10px rgba(244, 63, 94, 0.35);
}

/* Chứng nhận Năng Lực Số 2025 */
.certificate-frame {
  position: relative;
  background: linear-gradient(135deg, #ffffff 0%, #f0f9ff 100%);
  border: 3px double #0284c7;
  border-radius: 20px;
  padding: 24px;
  box-shadow: 0 15px 35px rgba(2, 132, 199, 0.15);
}

.dark .certificate-frame {
  background: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
  border-color: #38bdf8;
}

/* ==========================================================================
   UPGRADE 3: Đấu Trường Lớp Học & Bục Vinh Danh Top 3 (Podium)
   ========================================================================== */
.battle-widget {
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.08) 0%, rgba(244, 63, 94, 0.08) 100%);
  border: 1.5px solid rgba(56, 189, 248, 0.25);
  border-radius: 20px;
  padding: 20px;
}

.battle-progress-bar {
  height: 14px;
  border-radius: 7px;
  background: #f43f5e;
  overflow: hidden;
  position: relative;
}

.battle-progress-fill {
  height: 100%;
  background: #0284c7;
  transition: width 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.podium-container {
  display: flex;
  align-items: flex-end;
  justify-content: center;
  gap: 12px;
  padding: 20px 8px 10px;
}

.podium-slot {
  flex: 1;
  max-width: 220px;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  cursor: pointer;
  transition: transform 0.2s ease;
}

.podium-slot:hover {
  transform: translateY(-4px);
}

.podium-avatar-card {
  padding: 10px;
  border-radius: 16px;
  background: var(--bg-card);
  box-shadow: var(--neu-shadow-raised-sm);
  border: var(--neu-border);
  margin-bottom: 8px;
  width: 100%;
}

.podium-step {
  width: 100%;
  border-radius: 16px 16px 6px 6px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  font-weight: 800;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
  padding: 10px 4px;
}

.podium-step.rank-1 {
  height: 120px;
  background: linear-gradient(180deg, #f59e0b 0%, #b45309 100%);
  border: 2px solid #fbbf24;
}

.podium-step.rank-2 {
  height: 95px;
  background: linear-gradient(180deg, #94a3b8 0%, #475569 100%);
  border: 2px solid #cbd5e1;
}

.podium-step.rank-3 {
  height: 75px;
  background: linear-gradient(180deg, #d97706 0%, #78350f 100%);
  border: 2px solid #f97316;
}

/* Canvas Confetti */
#confetti-canvas {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 99999;
}

/* ==========================================================================
   UPGRADE 4: Bảng Tương Tác Cảm Xúc Live Peer-Reactions & Sân Khấu Tivi 60"
   ========================================================================== */
.reaction-dock {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 8px;
  border-radius: 16px;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.15);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
  overflow-x: auto;
  scrollbar-none: true;
}

.reaction-btn {
  min-height: 44px;
  min-width: 44px;
  padding: 6px 10px;
  border-radius: 14px;
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: rgba(255, 255, 255, 0.08);
  color: #ffffff;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  font-size: 15px;
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.34, 1.56, 0.64, 1);
  user-select: none;
  white-space: nowrap;
}

.reaction-btn:hover {
  transform: translateY(-2px) scale(1.08);
  background: rgba(255, 255, 255, 0.18);
  border-color: rgba(56, 189, 248, 0.5);
}

.reaction-btn:active {
  transform: scale(0.92);
}

.reaction-count-chip {
  font-size: 11px;
  font-weight: 800;
  font-family: monospace;
  opacity: 0.95;
}

/* Dải phản hồi thu nhỏ trên từng thẻ dự án */
.mini-reaction-bar {
  display: flex;
  align-items: center;
  gap: 4px;
  flex-wrap: wrap;
}

.mini-reaction-btn {
  min-height: 32px;
  padding: 3px 8px;
  border-radius: 10px;
  background: rgba(148, 163, 184, 0.12);
  border: 1px solid rgba(148, 163, 184, 0.2);
  color: var(--text-main);
  font-size: 11px;
  font-weight: 700;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: all 0.15s ease;
}

.mini-reaction-btn:hover {
  background: var(--accent-blue-light);
  border-color: var(--accent-blue);
  transform: scale(1.05);
}

.mini-reaction-btn:active {
  transform: scale(0.95);
}

/* Hiệu ứng bay bổng của reaction */
.flying-reaction {
  position: fixed;
  pointer-events: none;
  z-index: 999999;
  font-size: 32px;
  animation: flyUpAndWobble 2.2s cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
  will-change: transform, opacity;
  filter: drop-shadow(0 4px 12px rgba(0, 0, 0, 0.4));
}

@keyframes flyUpAndWobble {
  0% {
    opacity: 0;
    transform: translate(0, 0) scale(0.4) rotate(0deg);
  }
  15% {
    opacity: 1;
    transform: translate(var(--wobble-1, 10px), -50px) scale(1.4) rotate(var(--rot-1, -12deg));
  }
  50% {
    opacity: 0.95;
    transform: translate(var(--wobble-2, -18px), -160px) scale(1.2) rotate(var(--rot-2, 12deg));
  }
  80% {
    opacity: 0.6;
    transform: translate(var(--wobble-3, 12px), -260px) scale(1) rotate(var(--rot-3, -6deg));
  }
  100% {
    opacity: 0;
    transform: translate(var(--wobble-4, -8px), -360px) scale(0.8) rotate(var(--rot-4, 6deg));
  }
}

/* Sân Khấu Thuyết Trình Tivi 60 Inch (Cinema Stage Mode) */
.cinema-stage-overlay {
  position: fixed;
  inset: 0;
  z-index: 99990;
  background: rgba(10, 15, 29, 0.97);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.stage-top-bar {
  padding: 12px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  background: rgba(15, 23, 42, 0.85);
  color: #ffffff;
}

.stage-main-grid {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 20px;
  padding: 20px;
  height: calc(100vh - 65px);
  overflow: hidden;
}

@media (max-width: 1024px) {
  .stage-main-grid {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr auto;
    overflow-y: auto;
  }
}

.stage-iframe-container {
  position: relative;
  background: #000000;
  border-radius: 24px;
  overflow: hidden;
  box-shadow: 0 25px 60px rgba(0, 0, 0, 0.6), 0 0 0 2px rgba(56, 189, 248, 0.4);
  display: flex;
  flex-direction: column;
}

.stage-iframe-container iframe {
  width: 100%;
  height: 100%;
  border: none;
}

.stage-sidebar-panel {
  display: flex;
  flex-direction: column;
  gap: 16px;
  overflow-y: auto;
}

.stage-pitch-box {
  background: rgba(30, 41, 59, 0.8);
  border: 1.5px solid rgba(56, 189, 248, 0.3);
  border-radius: 20px;
  padding: 16px;
  text-align: center;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.pitch-digital-clock {
  font-family: monospace;
  font-size: 40px;
  font-weight: 900;
  color: #38bdf8;
  letter-spacing: 2px;
  text-shadow: 0 0 15px rgba(56, 189, 248, 0.5);
  margin: 6px 0;
}

.pitch-digital-clock.warning {
  color: #f43f5e;
  text-shadow: 0 0 15px rgba(244, 63, 94, 0.6);
  animation: pulseWarning 1s infinite;
}

@keyframes pulseWarning {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.8; transform: scale(1.03); }
}

.stage-reaction-stream-panel {
  position: relative;
  border-radius: 20px;
  background: rgba(15, 23, 42, 0.6);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 14px;
  overflow: hidden;
}

/* Sân Khấu Chiếu Đôi So Kèo Nội Bộ Lớp (Dual-Screen In-Class Clash) */
.stage-dual-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  height: 100%;
}

@media (max-width: 900px) {
  .stage-dual-container {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr 1fr;
  }
}

.stage-dual-card {
  position: relative;
  background: #000000;
  border-radius: 20px;
  overflow: hidden;
  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.5);
  display: flex;
  flex-direction: column;
}

.stage-dual-card.active-a {
  box-shadow: 0 0 0 2px #38bdf8, 0 15px 40px rgba(56, 189, 248, 0.3);
}

.stage-dual-card.active-b {
  box-shadow: 0 0 0 2px #f43f5e, 0 15px 40px rgba(244, 63, 94, 0.3);
}

.stage-dual-badge {
  position: absolute;
  top: 10px;
  left: 12px;
  z-index: 10;
  padding: 4px 10px;
  border-radius: 10px;
  font-size: 11px;
  font-weight: 800;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.4);
}

/* Thẻ Chấm Điểm Rubric 360 Tự Động Của Socratic AI */
.socratic-rubric-card {
  background: rgba(15, 23, 42, 0.05);
  border: 1px solid rgba(56, 189, 248, 0.3);
  border-radius: 16px;
  padding: 14px;
  margin-top: 12px;
}

.dark .socratic-rubric-card {
  background: rgba(15, 23, 42, 0.4);
}

.rubric-criteria-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 6px;
  font-size: 11px;
}

.rubric-bar-track {
  flex: 1;
  height: 6px;
  border-radius: 3px;
  background: rgba(148, 163, 184, 0.2);
  overflow: hidden;
}

.rubric-bar-fill {
  height: 100%;
  border-radius: 3px;
  transition: width 0.5s ease;
}

/* Đồng hồ săn bug tốc độ 60s */
.speed-debug-pill {
  font-family: monospace;
  font-size: 15px;
  font-weight: 900;
  padding: 3px 10px;
  border-radius: 9999px;
  background: rgba(244, 63, 94, 0.15);
  color: #f43f5e;
  border: 1px solid rgba(244, 63, 94, 0.3);
}

/* ==========================================================================
   Canva Pro & AI Code Studio Enhancements
   ========================================================================== */
.canva-pro-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: 9999px;
  font-size: 11px;
  font-weight: 800;
  background: linear-gradient(135deg, rgba(168, 85, 247, 0.15), rgba(236, 72, 153, 0.15));
  color: #a855f7;
  border: 1px solid rgba(168, 85, 247, 0.3);
}

.canva-bridge-card {
  border-radius: 18px;
  background: var(--bg-card);
  border: var(--neu-border);
  box-shadow: var(--neu-shadow-raised-sm);
  overflow: hidden;
  transition: all 0.3s ease;
}

.canva-bridge-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--neu-shadow-raised);
}

.canva-bridge-tab-btn {
  padding: 8px 16px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 700;
  transition: all 0.2s ease;
  cursor: pointer;
  border: 1px solid transparent;
  color: var(--text-muted);
}

.canva-bridge-tab-btn.active {
  background: #a855f7;
  color: #ffffff;
  box-shadow: 0 4px 12px rgba(168, 85, 247, 0.35);
}

.canva-prompt-card {
  border-radius: 16px;
  background: var(--bg-card);
  border: var(--neu-border);
  box-shadow: var(--neu-shadow-raised-sm);
  padding: 16px;
  transition: all 0.2s ease;
}

.canva-prompt-card:hover {
  border-color: rgba(168, 85, 247, 0.4);
}

/* ==========================================================================
   Syntax Cloze Challenge (Thử Thách Điền Khuyết Cú Pháp SGK)
   ========================================================================== */
.syntax-cloze-card {
  border-radius: 18px;
  background: var(--bg-card);
  border: var(--neu-border);
  box-shadow: var(--neu-shadow-raised);
  padding: 20px;
}

.cloze-code-snippet {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 13px;
  line-height: 1.7;
  background: #0f172a;
  color: #38bdf8;
  border-radius: 14px;
  padding: 16px;
  border: 1px solid rgba(56, 189, 248, 0.2);
  overflow-x: auto;
}

.cloze-blank {
  display: inline-block;
  min-width: 80px;
  padding: 2px 8px;
  margin: 0 4px;
  border-radius: 6px;
  background: rgba(244, 63, 94, 0.25);
  border: 1px dashed #f43f5e;
  color: #fca5a5;
  text-align: center;
  font-weight: 800;
  transition: all 0.2s ease;
}

.cloze-blank.filled-correct {
  background: rgba(16, 185, 129, 0.25);
  border: 1px solid #10b981;
  color: #6ee7b7;
}

.cloze-choice-btn {
  min-height: 44px;
  padding: 10px 18px;
  border-radius: 12px;
  font-family: ui-monospace, SFMono-Regular, monospace;
  font-size: 13px;
  font-weight: 700;
  background: var(--bg-app);
  border: 1px solid rgba(148, 163, 184, 0.3);
  color: var(--text-main);
  box-shadow: var(--neu-shadow-raised-sm);
  cursor: pointer;
  transition: all 0.2s ease;
}

.cloze-choice-btn:hover {
  border-color: #38bdf8;
  color: #0284c7;
  transform: translateY(-1px);
}

.cloze-choice-btn:active {
  box-shadow: var(--neu-shadow-inset);
  transform: scale(0.98);
}

.cloze-choice-btn.correct {
  background: #ecfdf5 !important;
  border-color: #10b981 !important;
  color: #065f46 !important;
  box-shadow: 0 0 0 2px #10b981 !important;
}

.dark .cloze-choice-btn.correct {
  background: #064e3b !important;
  color: #a7f3d0 !important;
}

.cloze-choice-btn.wrong {
  background: #fff1f2 !important;
  border-color: #f43f5e !important;
  color: #9f1239 !important;
  box-shadow: 0 0 0 2px #f43f5e !important;
}

.dark .cloze-choice-btn.wrong {
  background: #881337 !important;
  color: #fecdd3 !important;
}

/* ==========================================================================
   Interactive 5-Layer Prompt Builder & AI Code Inspector
   ========================================================================== */
.prompt-builder-pill {
  min-height: 38px;
  padding: 6px 14px;
  border-radius: 9999px;
  font-size: 11px;
  font-weight: 700;
  background: var(--bg-app);
  border: 1px solid rgba(148, 163, 184, 0.3);
  color: var(--text-main);
  box-shadow: var(--neu-shadow-raised-sm);
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.prompt-builder-pill:hover {
  border-color: #a855f7;
  color: #a855f7;
  transform: translateY(-1px);
}

.prompt-builder-pill.active {
  background: linear-gradient(135deg, #a855f7, #ec4899);
  color: #ffffff;
  border-color: transparent;
  box-shadow: 0 4px 12px rgba(168, 85, 247, 0.35);
}

.ai-inspector-report-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 10px 14px;
  border-radius: 12px;
  font-size: 11px;
  line-height: 1.5;
  margin-bottom: 8px;
}

.ai-inspector-report-item.pass {
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.3);
  color: #065f46;
}

.dark .ai-inspector-report-item.pass {
  color: #6ee7b7;
}

.ai-inspector-report-item.warn {
  background: rgba(245, 158, 11, 0.1);
  border: 1px solid rgba(245, 158, 11, 0.3);
  color: #92400e;
}

.dark .ai-inspector-report-item.warn {
  color: #fcd34d;
}

.ai-inspector-report-item.fail {
  background: rgba(244, 63, 94, 0.1);
  border: 1px solid rgba(244, 63, 94, 0.3);
  color: #9f1239;
}

.dark .ai-inspector-report-item.fail {
  color: #fca5a5;
}