/* ================================================================
   LIQUID GLASS DESIGN SYSTEM - Thẻ Bài Hướng Tâm
   Deep Glass Variant for Spiritual/Meditation App
   ================================================================ */

/* Import Inter font */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

:root {
  /* ============================================
     LIQUID GLASS COLOR SYSTEM - LIGHT THEME
     ============================================ */
  
  /* Light Foundation */
  --liquid-dark-bg: #F5F7FA;
  --liquid-dark-surface: #FFFFFF;
  --liquid-dark-elevated: #FAFBFC;
  
  /* Glass Material - Light Variant */
  --glass-bg: rgba(255, 255, 255, 0.65);
  --glass-bg-hover: rgba(255, 255, 255, 0.85);
  --glass-bg-active: rgba(255, 255, 255, 0.95);
  --glass-border: rgba(20, 108, 255, 0.1);
  --glass-border-strong: rgba(20, 108, 255, 0.2);
  --glass-blur: blur(16px);
  --glass-blur-strong: blur(20px);
  
  /* Accent Colors (Use ONE per screen) */
  --primary: #146CFF;           /* Electric Blue */
  --primary-rgb: 20, 108, 255;
  --accent: #FF6A00;            /* Signal Orange */
  --accent-rgb: 255, 106, 0;
  
  /* Text Colors - Light Theme */
  --text-primary: rgba(15, 23, 42, 0.95);
  --text-secondary: rgba(51, 65, 85, 0.85);
  --text-tertiary: rgba(100, 116, 139, 0.7);
  
  /* Shadows - Light Theme (More Subtle) */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.12);
  --shadow-glow-blue: 0 0 24px rgba(var(--primary-rgb), 0.2);
  --shadow-glow-orange: 0 0 24px rgba(var(--accent-rgb), 0.2);
  
  /* Spacing System (8px grid) */
  --space-xs: 8px;
  --space-sm: 16px;
  --space-md: 24px;
  --space-lg: 32px;
  --space-xl: 48px;
  --space-2xl: 64px;
  
  /* Border Radius */
  --radius-sm: 12px;
  --radius-md: 16px;
  --radius-lg: 20px;
  --radius-xl: 24px;
  
  /* Typography */
  --font-primary: 'Inter', 'Noto Sans Vietnamese', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-size-xs: 13px;
  --font-size-sm: 14px;
  --font-size-base: 16px;
  --font-size-lg: 18px;
  --font-size-xl: 20px;
  --font-size-2xl: 24px;
  --font-size-3xl: 32px;
  --font-size-4xl: 40px;
  
  /* Transitions (Fluid & Controlled) */
  --transition-fast: 120ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 280ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-modal: 320ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ============================================
   BASE STYLES
   ============================================ */

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

html, body {
  min-height: 100%;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-primary);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--text-primary);
  background: linear-gradient(135deg, #F5F7FA 0%, #E3E8F0 100%);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* Subtle gradient overlay - Light Theme */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(
    ellipse at top,
    rgba(20, 108, 255, 0.06) 0%,
    rgba(255, 255, 255, 0) 50%
  );
  pointer-events: none;
  z-index: -1;
}

/* ============================================
   GLASS MATERIAL COMPONENTS
   ============================================ */

.glass-card {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  box-shadow: 
    var(--shadow-md),
    inset 0 1px 0 rgba(255, 255, 255, 0.5);
  transition: all var(--transition-base);
}

.glass-card-strong {
  background: var(--glass-bg-hover);
  backdrop-filter: var(--glass-blur-strong);
  -webkit-backdrop-filter: var(--glass-blur-strong);
  border: 1px solid var(--glass-border-strong);
}

/* ============================================
   STEP CONTAINER (All 8 Steps)
   ============================================ */

.step-container {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 80vh;
  text-align: center;
  padding: var(--space-md);
  width: 100%;
  animation: liquidFadeIn var(--transition-modal);
}

@media screen and (min-width: 768px) {
  .step-container {
    max-width: 1200px;
    margin: var(--space-md) auto;
    padding: var(--space-2xl);
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur-strong);
    -webkit-backdrop-filter: var(--glass-blur-strong);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    box-shadow: 
      var(--shadow-lg),
      inset 0 1px 0 rgba(255, 255, 255, 0.8);
    min-height: 70vh;
  }
}

.step-title {
  font-size: var(--font-size-2xl);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-lg);
  letter-spacing: -0.02em;
}

@media screen and (min-width: 768px) {
  .step-title {
    font-size: var(--font-size-3xl);
    margin-bottom: var(--space-xl);
  }
}

.step-content {
  margin-bottom: var(--space-lg);
  width: 100%;
  max-width: 100%;
}

@media screen and (min-width: 768px) {
  .step-content {
    max-width: 900px;
  }
}

/* ============================================
   BUTTONS (Liquid Glass Style)
   ============================================ */

.btn {
  display: inline-block;
  font-family: var(--font-primary);
  font-size: var(--font-size-base);
  font-weight: 500;
  line-height: 1.5;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
  user-select: none;
  border: none;
  padding: 12px 24px;
  border-radius: 30px;
  transition: all var(--transition-fast);
  width: 100%;
  
  /* Glass button - primary - Light Theme */
  background: rgba(var(--primary-rgb), 0.12);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(var(--primary-rgb), 0.25);
  color: var(--primary);
  box-shadow: 
    0 2px 12px rgba(var(--primary-rgb), 0.12),
    inset 0 1px 0 rgba(255, 255, 255, 0.6);
}

.btn:hover {
  background: rgba(var(--primary-rgb), 0.2);
  border-color: rgba(var(--primary-rgb), 0.4);
  transform: translateY(-2px);
  box-shadow: 
    0 4px 20px rgba(var(--primary-rgb), 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.8);
}

.btn:active {
  transform: translateY(0);
  box-shadow: 
    0 2px 8px rgba(var(--primary-rgb), 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

.btn-outline {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  color: var(--text-primary);
  box-shadow: var(--shadow-sm);
}

.btn-outline:hover {
  background: var(--glass-bg-hover);
  border-color: var(--glass-border-strong);
  transform: translateY(-2px);
}

@media screen and (min-width: 768px) {
  .btn {
    max-width: 400px;
    padding: 14px 32px;
    font-size: var(--font-size-lg);
  }
  
  .btn-outline {
    max-width: 400px;
  }
}

/* ============================================
   STEP 1: WELCOME / START
   ============================================ */

.start-container {
  text-align: center;
  max-width: 600px;
  margin: 0 auto;
}

@media screen and (min-width: 768px) {
  .start-container {
    max-width: 700px;
    padding: var(--space-xl);
    background: rgba(255, 255, 255, 0.5);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border: none;
    border-radius: var(--radius-xl);
    box-shadow: none;
  }
}

.start-container .logo {
  width: 120px;
  height: 120px;
  margin: 0 auto var(--space-lg);
  filter: drop-shadow(0 4px 16px rgba(var(--primary-rgb), 0.3));
}

@media screen and (min-width: 768px) {
  .start-container .logo {
    width: 150px;
    height: 150px;
  }
}

.start-container h1 {
  font-size: var(--font-size-3xl);
  font-weight: 600;
  margin-bottom: var(--space-md);
  letter-spacing: -0.02em;
}

@media screen and (min-width: 768px) {
  .start-container h1 {
    font-size: var(--font-size-4xl);
    margin-bottom: var(--space-lg);
  }
}

.start-container p {
  font-size: var(--font-size-base);
  line-height: 1.8;
  color: var(--text-secondary);
  max-height: 350px;
  overflow-y: auto;
  text-align: justify;
}

@media screen and (min-width: 768px) {
  .start-container p {
    font-size: var(--font-size-lg);
  }
}

/* ============================================
   STEP 2: BREATH / MEDITATION
   ============================================ */

.breath-container {
  position: relative;
}

@media screen and (min-width: 768px) {
  .breath-container {
    padding: var(--space-xl);
  }
}

.breath-square {
  background: rgba(var(--primary-rgb), 0.1);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid rgba(var(--primary-rgb), 0.25);
  box-shadow: 
    0 0 40px rgba(var(--primary-rgb), 0.25),
    inset 0 0 20px rgba(var(--primary-rgb), 0.15);
  animation: liquidGlow 15s infinite ease-in-out;
}

@media screen and (min-width: 768px) {
  .breath-square {
    width: 280px !important;
    height: 280px !important;
  }
}

@keyframes liquidGlow {
  0%, 100% { 
    box-shadow: 
      0 0 30px rgba(var(--primary-rgb), 0.25),
      inset 0 0 15px rgba(var(--primary-rgb), 0.12);
  }
  50% { 
    box-shadow: 
      0 0 50px rgba(var(--primary-rgb), 0.4),
      inset 0 0 25px rgba(var(--primary-rgb), 0.2);
  }
}

.breath-container p {
  font-size: var(--font-size-base);
  color: var(--text-secondary);
}

@media screen and (min-width: 768px) {
  .breath-container p {
    font-size: var(--font-size-lg);
    margin-top: var(--space-lg);
  }
}

.breath-timer {
  font-size: 11px;
  font-weight: 400;
  color: var(--text-tertiary);
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--glass-border);
  display: inline-block;
  padding: 6px 16px;
  border-radius: 20px;
  box-shadow: var(--shadow-sm);
}

@media screen and (min-width: 768px) {
  .breath-timer-container {
    margin-top: 25px !important;
  }
}

/* Music controls */
.music-controls {
  position: absolute;
  top: 30px;
  right: 30px;
  z-index: 100;
}

@media (max-width: 768px) {
  .music-controls {
    top: 20px;
    right: 20px;
  }
}

.btn-icon {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 20px;
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-sm);
}

.btn-icon:hover {
  background: var(--glass-bg-hover);
  transform: scale(1.05);
  box-shadow: var(--shadow-md);
}

/* ============================================
   STEP 3: INTENTION / FORM
   ============================================ */

.intention-box {
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-left: 3px solid var(--primary);
  border-radius: var(--radius-sm);
  padding: var(--space-md);
  margin-bottom: var(--space-md);
  text-align: left;
  box-shadow: var(--shadow-sm);
  max-width: 600px;
  width: 100%;
  border: 1px solid rgba(var(--primary-rgb), 0.15);
}

@media screen and (min-width: 768px) {
  .intention-box {
    max-width: 700px;
    padding: var(--space-lg);
    margin-bottom: var(--space-xl);
  }
}

.intention-box h4 {
  font-size: var(--font-size-base);
  font-weight: 500;
  color: var(--primary);
  margin-bottom: var(--space-xs);
}

@media screen and (min-width: 768px) {
  .intention-box h4 {
    font-size: var(--font-size-lg);
  }
}

.intention-box p {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  font-style: italic;
  max-height: 80px;
  overflow-y: auto;
}

@media screen and (min-width: 768px) {
  .intention-box p {
    font-size: var(--font-size-base);
  }
}

/* Tabs */
.tab-buttons {
  display: flex;
  margin-bottom: var(--space-md);
  border-bottom: 1px solid var(--glass-border);
  gap: var(--space-xs);
}

.tab-btn {
  padding: 12px 20px;
  background: none;
  border: none;
  cursor: pointer;
  font-size: var(--font-size-base);
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
  position: relative;
  border-radius: var(--radius-sm) var(--radius-sm) 0 0;
}

.tab-btn:hover {
  background: var(--glass-bg);
  color: var(--text-primary);
}

.tab-btn.active {
  color: var(--primary);
  background: var(--glass-bg);
}

.tab-btn.active::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--primary);
  box-shadow: 0 0 8px rgba(var(--primary-rgb), 0.5);
}

/* Form elements */
.intention-form textarea {
  width: 100%;
  height: 150px;
  padding: var(--space-md);
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-family: var(--font-primary);
  font-size: var(--font-size-base);
  line-height: 1.6;
  resize: none;
  transition: all var(--transition-base);
  box-shadow: var(--shadow-sm);
}

.intention-form textarea::placeholder {
  color: var(--text-tertiary);
}

.intention-form textarea:focus {
  background: rgba(255, 255, 255, 0.9);
  border-color: rgba(var(--primary-rgb), 0.4);
  outline: none;
  box-shadow: 
    0 0 0 3px rgba(var(--primary-rgb), 0.12),
    var(--shadow-md);
}

@media screen and (min-width: 768px) {
  .intention-form textarea {
    height: 180px;
    padding: var(--space-lg);
  }
  
  .tabs-container {
    max-width: 700px !important;
  }
}

/* Topic buttons */
.topic-buttons {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: var(--space-md);
  margin-bottom: var(--space-md);
}

@media screen and (min-width: 768px) {
  .topic-buttons {
    gap: var(--space-lg);
  }
}

.topic-btn {
  padding: var(--space-md);
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--font-size-base);
  font-weight: 400;
  color: var(--text-primary);
  transition: all var(--transition-base);
  text-align: center;
  box-shadow: var(--shadow-sm);
}

.topic-btn:hover {
  background: var(--glass-bg-hover);
  border-color: var(--glass-border-strong);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.topic-btn.selected {
  background: rgba(var(--primary-rgb), 0.15);
  border-color: var(--primary);
  color: var(--primary);
  box-shadow: 
    var(--shadow-glow-blue),
    inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

@media screen and (min-width: 768px) {
  .topic-btn {
    padding: var(--space-lg);
    font-size: var(--font-size-lg);
  }
}

/* ============================================
   STEP 4: SHUFFLE CARDS
   ============================================ */

.shuffle-container {
  position: relative;
  height: 300px;
  width: 100%;
  perspective: 1000px;
  margin-bottom: var(--space-lg);
}

.card-deck {
  position: absolute;
  width: 200px;
  height: 300px;
  left: 50%;
  transform: translateX(-50%);
  transform-style: preserve-3d;
}

.card-back {
  width: 200px;
  height: 300px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--primary), var(--accent));
  box-shadow: 
    var(--shadow-lg),
    0 0 20px rgba(var(--primary-rgb), 0.3);
  border: 1px solid var(--glass-border-strong);
  position: absolute;
  backface-visibility: hidden;
  background-size: cover;
  background-position: center;
}

.shuffle-animation {
  animation: shuffle 0.8s ease-in-out infinite;
}

@keyframes shuffle {
  0% { transform: translateX(-50%) translateY(0) rotate(0); }
  25% { transform: translateX(-60%) translateY(-5px) rotate(-5deg); }
  50% { transform: translateX(-40%) translateY(0) rotate(5deg); }
  75% { transform: translateX(-55%) translateY(-3px) rotate(-2deg); }
  100% { transform: translateX(-50%) translateY(0) rotate(0); }
}

/* ============================================
   STEP 5 & 6: CARDS GRID & FAN
   ============================================ */

/* Khu vực hiển thị quạt bài */
.fan-container {
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  transform-style: preserve-3d;
  perspective: 1000px;
}

/* Lá bài kiểu quạt */
.fan-card {
  width: 100px;
  height: 150px;
  border-radius: var(--radius-sm);
  background: transparent;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--glass-border);
  position: absolute;
  top: 50%;
  left: 50%;
  transform-origin: bottom center;
  cursor: pointer;
  transition: all 0.5s ease;
  backface-visibility: hidden;
  transform-style: preserve-3d;
  perspective: 1000px;
  z-index: 1;
}

/* Animation cho hiệu ứng trải bài quạt */
@keyframes fanCardAppear {
  0% {
    opacity: 0;
    transform: rotate(0deg) translateY(50px) translateX(-50%);
  }
  100% {
    opacity: 1;
    transform: rotate(var(--card-angle)) translateY(-120px) translateX(-50%);
  }
}

.fan-card-appear {
  animation: fanCardAppear 0.7s forwards;
}

.fan-card:hover {
  transform: rotate(var(--card-angle)) translateY(-130px) translateX(-50%) scale(1.05);
  box-shadow: var(--shadow-md);
  z-index: 10;
}

.fan-card:hover .card-back {
  opacity: 0.3;
}

.cards-grid {
  position: relative;
  min-height: 400px;
  margin-bottom: var(--space-xl);
  width: 100%;
  display: flex;
  justify-content: center;
  align-items: flex-start;
}

@media screen and (min-width: 768px) {
  .cards-grid {
    min-height: 500px;
    padding: var(--space-md) 0;
  }
}

.grid-container {
  display: grid;
  grid-template-columns: repeat(3, minmax(90px, 1fr));
  gap: 10px;
  width: 100%;
  min-width: 300px;
  max-width: 100%;
  padding: 10px;
  margin: 0 auto;
  box-sizing: border-box;
  max-height: 450px;
  overflow-y: auto;
  grid-auto-rows: minmax(140px, auto);
  padding-bottom: var(--space-md);
  justify-content: center;
}

/* Responsive grid */
@media screen and (max-width: 380px) {
  .grid-container {
    grid-template-columns: repeat(2, 1fr);
    gap: 8px;
    max-height: 420px;
  }
}

@media screen and (min-width: 381px) and (max-width: 480px) {
  .grid-container {
    grid-template-columns: repeat(3, 1fr);
    gap: 8px;
    max-width: 480px;
    margin: 0 auto;
  }
}

@media screen and (min-width: 481px) and (max-width: 767px) {
  .grid-container {
    grid-template-columns: repeat(3, 1fr);
    max-width: 560px;
    margin: 0 auto;
  }
}

@media screen and (min-width: 768px) {
  .grid-container {
    grid-template-columns: repeat(4, 1fr);
    max-width: 800px;
    gap: var(--space-md);
    padding: var(--space-md);
    margin: 0 auto;
    justify-content: center;
  }
}

@media screen and (min-width: 1024px) {
  .grid-container {
    grid-template-columns: repeat(5, 1fr);
    max-width: 900px;
    gap: var(--space-md);
    margin: 0 auto;
    justify-content: center;
  }
}

.grid-container-appear {
  animation: gridContainerAppear 0.8s forwards;
}

@keyframes gridContainerAppear {
  0% {
    opacity: 0;
    transform: translateY(30px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Card items */
.card-item {
  width: 100%;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--glass-border);
  position: relative;
  cursor: pointer;
  transition: all var(--transition-base);
  aspect-ratio: 2/3;
  box-shadow: var(--shadow-sm);
}

.card-item:hover {
  background: rgba(255, 255, 255, 0.85);
  border-color: rgba(var(--primary-rgb), 0.35);
  transform: translateY(-3px) scale(1.02);
  box-shadow: 
    0 8px 24px rgba(var(--primary-rgb), 0.18),
    var(--shadow-md);
  z-index: 10;
}

.card-item.card-selected {
  background: rgba(var(--primary-rgb), 0.15);
  border: 2px solid var(--primary);
  box-shadow: 
    0 0 24px rgba(var(--primary-rgb), 0.35),
    inset 0 1px 0 rgba(255, 255, 255, 0.8);
  z-index: 20;
}

.card-image {
  width: 100%;
  height: 100%;
  border-radius: var(--radius-sm);
  position: absolute;
  top: 0;
  left: 0;
  background-size: contain;
  background-position: center;
  background-repeat: no-repeat;
  background-color: rgba(255, 255, 255, 0.3);
  z-index: 1;
}

.card-back {
  width: 100%;
  height: 100%;
  position: absolute;
  top: 0;
  left: 0;
  border-radius: var(--radius-sm);
  z-index: 2;
  opacity: 0.85;
  transition: opacity var(--transition-base);
  background: rgba(255, 255, 255, 0.4);
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
}

.card-item.card-hover .card-back {
  opacity: 0.3;
}

.card-item.card-selected .card-back {
  opacity: 0;
}

/* Card animations */
.card-appear-animation {
  animation: cardAppear 0.5s ease forwards;
}

@keyframes cardAppear {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.9);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* ============================================
   STEP 7: RESULT / CARDS DISPLAY
   ============================================ */

.result-container {
  /* Inherits step-container styles */
}

.card-result-container {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  margin: var(--space-md) 0;
  justify-content: center;
}

@media screen and (min-width: 768px) {
  .card-result-container {
    display: grid;
    grid-template-columns: repeat(2, minmax(300px, 1fr));
    gap: var(--space-xl);
    max-width: 900px;
    margin: var(--space-xl) auto;
    align-items: start;
  }
}

.card-image-container {
  max-width: 300px;
  text-align: center;
  position: relative;
}

@media screen and (min-width: 768px) {
  .card-image-container {
    grid-column: 1 / -1;
    max-width: 100% !important;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-xl);
  }
}

.card-front, .card-back-view {
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  padding: var(--space-sm);
  box-shadow: var(--shadow-md);
}

@media screen and (min-width: 768px) {
  .rotate-btn-container {
    grid-column: 1 / -1;
  }
  
  .card-front, .card-back-view {
    width: 100%;
  }
}

.card-front img, .card-back-view img {
  width: 100%;
  max-height: 500px;
  object-fit: contain;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
  margin-bottom: var(--space-md);
  cursor: pointer;
  transition: transform var(--transition-slow);
  border: 1px solid var(--glass-border);
}

@media screen and (min-width: 768px) {
  .card-front img, .card-back-view img {
    max-height: 600px;
  }
}

.card-front img:hover, .card-back-view img:hover {
  transform: scale(1.02);
}

img.reversed {
  transform: rotate(180deg);
}

.rotate-card-btn {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: 20px;
  padding: 8px 16px;
  font-size: var(--font-size-sm);
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-sm);
}

.rotate-card-btn:hover {
  background: var(--glass-bg-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

/* Card meaning sections */
.card-meaning {
  flex: 1;
  min-width: 300px;
  max-width: 600px;
}

.meaning-section {
  margin-bottom: var(--space-md);
  padding: var(--space-md);
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.meaning-section h3 {
  color: var(--text-primary);
  font-size: var(--font-size-lg);
  font-weight: 500;
  margin-bottom: var(--space-sm);
  border-bottom: 1px solid var(--glass-border);
  padding-bottom: var(--space-xs);
}

.meaning-section p {
  color: var(--text-secondary);
  line-height: 1.7;
}

.quote {
  font-style: italic;
  padding: var(--space-md);
  background: rgba(var(--primary-rgb), 0.05);
  border-left: 3px solid var(--primary);
  border-radius: var(--radius-sm);
}

/* ============================================
   STEP 8: CTA / FINAL
   ============================================ */

.final-step {
  padding-bottom: var(--space-2xl);
}

@media screen and (min-width: 768px) {
  .final-step {
    padding: var(--space-2xl);
  }
}

.cta-container {
  max-width: 600px;
  margin: 0 auto;
}

.cta-card {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-slow);
  box-shadow: var(--shadow-md);
  margin-bottom: var(--space-md);
}

.cta-card:hover {
  background: var(--glass-bg-hover);
  border-color: rgba(var(--accent-rgb), 0.3);
  transform: translateY(-4px);
  box-shadow: 
    var(--shadow-lg),
    0 0 24px rgba(var(--accent-rgb), 0.15);
}

.cta-card-content {
  padding: var(--space-xl);
  text-align: center;
}

@media screen and (max-width: 767px) {
  .cta-card-content {
    padding: var(--space-md);
  }
}

.cta-card h3 {
  margin-top: 0;
  margin-bottom: var(--space-sm);
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--text-primary);
}

@media screen and (max-width: 767px) {
  .cta-card h3 {
    font-size: var(--font-size-lg);
  }
}

.cta-card p {
  margin-bottom: var(--space-md);
  color: var(--text-secondary);
  font-size: var(--font-size-base);
  line-height: 1.6;
}

@media screen and (max-width: 767px) {
  .cta-card p {
    font-size: var(--font-size-sm);
  }
}

.btn-gradient {
  background: linear-gradient(
    135deg, 
    rgba(var(--accent-rgb), 0.8) 0%, 
    rgba(var(--accent-rgb), 0.6) 100%
  );
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid rgba(var(--accent-rgb), 0.4);
  color: white;
  padding: 12px 30px;
  border-radius: 25px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: all var(--transition-base);
  font-weight: 500;
  text-decoration: none;
  box-shadow: 
    0 4px 12px rgba(var(--accent-rgb), 0.3),
    inset 0 1px 0 rgba(255, 255, 255, 0.2);
  font-size: var(--font-size-base);
}

.btn-gradient:hover {
  background: linear-gradient(
    135deg, 
    rgba(var(--accent-rgb), 0.9) 0%, 
    rgba(var(--accent-rgb), 0.7) 100%
  );
  transform: translateY(-2px);
  box-shadow: 
    0 6px 18px rgba(var(--accent-rgb), 0.4),
    inset 0 1px 0 rgba(255, 255, 255, 0.25);
}

.action-buttons {
  margin-top: var(--space-xl);
  text-align: center;
}

.btn-restart {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--glass-border);
  padding: 12px 30px;
  border-radius: 25px;
  font-weight: 500;
  transition: all var(--transition-base);
  cursor: pointer;
  font-size: var(--font-size-base);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  box-shadow: var(--shadow-sm);
}

.btn-restart:hover {
  background: var(--glass-bg-hover);
  border-color: var(--glass-border-strong);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-restart svg {
  width: 20px;
  height: 20px;
}

/* ============================================
   ANIMATIONS
   ============================================ */

@keyframes liquidFadeIn {
  from {
    opacity: 0;
    transform: translateY(8px) scale(0.98);
    filter: blur(4px);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
    filter: blur(0);
  }
}

/* ============================================
   MODALS
   ============================================ */

.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  padding-top: 50px;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background: rgba(245, 247, 250, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  animation: liquidFadeIn var(--transition-modal);
}

.modal.active {
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-content {
  max-width: 90%;
  max-height: 80vh;
  object-fit: contain;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--glass-border);
  animation: liquidFadeIn var(--transition-modal);
}

.close-modal {
  position: absolute;
  top: 15px;
  right: 35px;
  color: var(--text-primary);
  font-size: 40px;
  font-weight: 300;
  transition: all var(--transition-fast);
  cursor: pointer;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.5);
}

.close-modal:hover {
  color: var(--primary);
  transform: scale(1.1);
}

/* ============================================
   LOADING & SPINNER
   ============================================ */

.loading-spinner {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  z-index: 1;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid rgba(var(--primary-rgb), 0.2);
  border-radius: 50%;
  border-top-color: var(--primary);
  animation: spin 1s linear infinite;
}

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* ============================================
   SCROLLBAR STYLING (Optional)
   ============================================ */

::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: rgba(20, 108, 255, 0.05);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb {
  background: rgba(20, 108, 255, 0.2);
  border-radius: 4px;
  transition: background var(--transition-fast);
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(20, 108, 255, 0.35);
}

/* ============================================
   BUTTON ANIMATIONS
   ============================================ */

/* Smooth fade-in cho nút sau khi xáo bài */
@keyframes buttonFadeIn {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ============================================
   UTILITY CLASSES
   ============================================ */

.text-primary { color: var(--text-primary); }
.text-secondary { color: var(--text-secondary); }
.text-tertiary { color: var(--text-tertiary); }

.mb-xs { margin-bottom: var(--space-xs); }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }

.mt-xs { margin-top: var(--space-xs); }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }

/* ============================================
   FOOTER STYLES
   ============================================ */

footer {
  text-align: center;
  padding: 30px 20px;
  background: rgba(255, 255, 255, 0.5);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-top: 1px solid rgba(20, 108, 255, 0.1);
  margin-top: 40px;
}

footer p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.6;
}

@media screen and (min-width: 768px) {
  footer {
    padding: 40px 20px;
  }
  
  footer p {
    font-size: 15px;
  }
}

/* ============================================
   PRINT STYLES
   ============================================ */

@media print {
  body {
    background: white;
    color: black;
  }
  
  .glass-card,
  .step-container {
    background: white;
    border: 1px solid #ddd;
    backdrop-filter: none;
  }
  
  footer {
    background: white;
    border-top: 1px solid #ddd;
  }
}