/* ========================================
   RDC MCQ - MODERN UI THEME
   Vibrant colors, smooth animations, modern aesthetics
   ======================================== */

:root {
  /* Vibrant Color Palette */
  --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --accent-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --success-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
  --gold-gradient: linear-gradient(135deg, #f7971e 0%, #ffd200 100%);

  --primary: #667eea;
  --primary-dark: #5568d3;
  --accent: #f093fb;
  --success: #00f2fe;
  --danger: #fe5f7e;
  --warning: #ffd200;

  /* Neutral Colors */
  --bg-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --bg-light: #f7f8fc;
  --card-bg: #ffffff;
  --text-main: #1a202c;
  --text-muted: #718096;
  --border-color: rgba(226, 232, 240, 0.8);

  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(102, 126, 234, 0.1);
  --shadow-md: 0 4px 12px rgba(102, 126, 234, 0.15);
  --shadow-lg: 0 10px 30px rgba(102, 126, 234, 0.25);
  --shadow-glow: 0 0 20px rgba(102, 126, 234, 0.3);

  /* Effects */
  --radius: 16px;
  --radius-sm: 8px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 20px;
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg-light);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  position: relative;
}

/* Animated background */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, #667eea22 0%, #764ba222 50%, #f093fb22 100%);
  z-index: -1;
  animation: gradientShift 15s ease infinite;
}

@keyframes gradientShift {

  0%,
  100% {
    opacity: 0.3;
    transform: translateY(0) scale(1);
  }

  50% {
    opacity: 0.5;
    transform: translateY(-20px) scale(1.05);
  }
}

/* Layout */
.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 1rem;
}

h1 {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 800;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-align: center;
  margin-bottom: 2rem;
  letter-spacing: -0.02em;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  animation: fadeInDown 0.6s ease-out;
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.logo-img {
  height: 50px;
  width: auto;
  filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.1));
  animation: float 3s ease-in-out infinite;
}

@keyframes float {

  0%,
  100% {
    transform: translateY(0px);
  }

  50% {
    transform: translateY(-10px);
  }
}

h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  margin: 0 0 1rem 0;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

h2::before {
  content: '';
  width: 4px;
  height: 24px;
  background: var(--primary-gradient);
  border-radius: 2px;
}

h3 {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text-main);
  margin: 0 0 0.75rem 0;
}

/* Grid Layout */
.layout-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 1024px) {
  .layout-grid {
    grid-template-columns: 1.5fr 1.5fr;
    gap: 2rem;
  }
}

.main-column,
.side-column {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  animation: fadeIn 0.6s ease-out;
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

/* Cards with Glassmorphism */
.card {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-md);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: var(--primary-gradient);
  opacity: 0;
  transition: var(--transition);
}

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

.card:hover::before {
  opacity: 1;
}

.hidden {
  display: none !important;
}

/* Forms */
.form-group {
  margin-bottom: 1.25rem;
  animation: slideInLeft 0.4s ease-out;
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-10px);
  }

  to {
    opacity: 1;
    transform: translateX(0);
  }
}

label {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

input[type="text"],
input[type="number"],
input[type="file"] {
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 0.9375rem;
  font-family: inherit;
  border: 2px solid var(--border-color);
  border-radius: var(--radius-sm);
  background-color: rgba(255, 255, 255, 0.8);
  transition: var(--transition);
}

input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(102, 126, 234, 0.1);
  background-color: #fff;
}

input:hover {
  border-color: var(--primary);
}

/* Buttons with Gradient */
.btn {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  padding: 0.875rem 1.75rem;
  font-size: 1rem;
  font-weight: 600;
  color: #fff;
  background: var(--primary-gradient);
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.3);
  transform: translate(-50%, -50%);
  transition: width 0.6s, height 0.6s;
}

.btn:hover::before {
  width: 300px;
  height: 300px;
}

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

.btn:active {
  transform: translateY(0);
}

.btn:disabled {
  background: linear-gradient(135deg, #cbd5e0, #a0aec0);
  cursor: not-allowed;
  opacity: 0.6;
}

.btn:disabled:hover {
  transform: none;
}

/* Success button variant */
.btn[style*="background-color:var(--success)"],
.btn[style*="background-color: var(--success)"] {
  background: var(--success-gradient) !important;
}

/* Session Code Display */
.session-code {
  font-family: 'Courier New', monospace;
  font-size: 2rem;
  font-weight: 800;
  background: var(--primary-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-align: center;
  letter-spacing: 0.2em;
  padding: 1rem;
  border-radius: var(--radius-sm);
  background-color: rgba(102, 126, 234, 0.05);
  border: 2px dashed var(--primary);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {

  0%,
  100% {
    transform: scale(1);
  }

  50% {
    transform: scale(1.02);
  }
}

/* Status Messages */
.status-message {
  margin-top: 0.75rem;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 500;
  animation: slideInUp 0.4s ease-out;
}

@keyframes slideInUp {
  from {
    opacity: 0;
    transform: translateY(10px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Question Options */
.options-grid {
  display: grid;
  gap: 0.875rem;
  margin-top: 1.5rem;
}

.option-card {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.9), rgba(247, 248, 252, 0.9));
  border: 2px solid var(--border-color);
  padding: 1rem 1.25rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  font-weight: 500;
  font-size: 1rem;
  position: relative;
  overflow: hidden;
}

.option-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(102, 126, 234, 0.1), transparent);
  transition: left 0.5s;
}

.option-card:hover:not(.disabled)::before {
  left: 100%;
}

.option-card:hover:not(.disabled) {
  border-color: var(--primary);
  transform: translateX(8px);
  box-shadow: var(--shadow-md);
  background: linear-gradient(135deg, rgba(102, 126, 234, 0.05), rgba(118, 75, 162, 0.05));
}

.option-card.selected {
  background: var(--primary-gradient);
  color: white;
  border-color: transparent;
  transform: scale(1.02);
  box-shadow: var(--shadow-glow);
}

.option-card.disabled {
  opacity: 0.5;
  cursor: default;
}

/* Leaderboard Styling */
.leaderboard-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  margin-top: 1rem;
}

.leaderboard-table thead th {
  text-align: left;
  padding: 1rem 1.25rem;
  background: linear-gradient(135deg, rgba(102, 126, 234, 0.1), rgba(118, 75, 162, 0.1));
  font-size: 0.875rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--text-muted);
  letter-spacing: 0.05em;
  border-bottom: 2px solid var(--border-color);
}

.leaderboard-table thead th:first-child {
  border-top-left-radius: var(--radius-sm);
}

.leaderboard-table thead th:last-child {
  border-top-right-radius: var(--radius-sm);
}

.leaderboard-table tbody td {
  padding: 1.25rem 1.25rem;
  border-bottom: 1px solid var(--border-color);
  font-size: 1.25rem;
  font-weight: 700;
}

.leaderboard-row {
  transition: var(--transition);
  animation: slideInRight 0.5s ease-out backwards;
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(20px);
  }

  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.leaderboard-row:nth-child(1) {
  animation-delay: 0.1s;
}

.leaderboard-row:nth-child(2) {
  animation-delay: 0.2s;
}

.leaderboard-row:nth-child(3) {
  animation-delay: 0.3s;
}

.leaderboard-row:nth-child(4) {
  animation-delay: 0.4s;
}

.leaderboard-row:nth-child(5) {
  animation-delay: 0.5s;
}

.leaderboard-row:hover {
  background: rgba(102, 126, 234, 0.03);
  transform: translateX(4px);
}

/* Rank Badge - Enhanced */
.rank-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  font-size: 1rem;
  font-weight: 800;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

/* Gold - Rank 1 */
.rank-1 .rank-badge {
  background: linear-gradient(135deg, #e2e8f0, #cbd5e0);
  color: #475569;
  box-shadow: 0 4px 12px rgba(203, 213, 224, 0.5);
  animation: silverPulse 2s ease-in-out infinite;
  width: 40px;
  height: 40px;
  font-size: 1.125rem;
}

@keyframes silverPulse {

  0%,
  100% {
    box-shadow: 0 4px 12px rgba(203, 213, 224, 0.5);
  }

  50% {
    box-shadow: 0 6px 20px rgba(203, 213, 224, 0.7);
  }
}

.rank-1 td {
  background: linear-gradient(90deg, rgba(226, 232, 240, 0.3), transparent);
  color: #475569;
  font-weight: 800;
  font-size: 1.5rem;
}

.rank-1 .player-name {
  font-size: 2rem;
  font-weight: 800;
  color: #475569;
}

.rank-1 .player-name::after {
  content: ' 🥈';
  animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {

  0%,
  100% {
    transform: translateY(0);
  }

  50% {
    transform: translateY(-4px);
  }
}

/* Silver - Rank 2 */
.rank-2 .rank-badge {
  background: linear-gradient(135deg, #e2e8f0, #cbd5e0);
  color: #475569;
  box-shadow: 0 4px 12px rgba(203, 213, 224, 0.4);
  width: 40px;
  height: 40px;
  font-size: 1.125rem;
}

.rank-2 td {
  background: linear-gradient(90deg, rgba(226, 232, 240, 0.25), transparent);
  color: #475569;
  font-weight: 800;
  font-size: 1.5rem;
}

.rank-2 .player-name {
  font-size: 2rem;
  font-weight: 800;
  color: #475569;
}

.rank-2 .player-name::after {
  content: ' 🥈';
}

/* Bronze - Rank 3 */
.rank-3 .rank-badge {
  background: linear-gradient(135deg, #fed7aa, #fdba74);
  color: #9a3412;
  box-shadow: 0 4px 12px rgba(254, 215, 170, 0.4);
}

.rank-3 td {
  background: linear-gradient(90deg, rgba(254, 215, 170, 0.2), transparent);
  color: #7c2d12;
  font-weight: 600;
}

/* Other ranks */
.rank-badge {
  background: linear-gradient(135deg, #f1f5f9, #e2e8f0);
  color: #64748b;
}

.player-name {
  font-weight: 700;
  font-size: 1.125rem;
}

/* Progress Bar */
.progress-container {
  height: 6px;
  background: rgba(226, 232, 240, 0.5);
  border-radius: 3px;
  margin-bottom: 1.5rem;
  overflow: hidden;
  position: relative;
}

.progress-bar {
  height: 100%;
  background: var(--primary-gradient);
  transition: width 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 0 10px rgba(102, 126, 234, 0.5);
}

.progress-bar::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  animation: progressShine 2s infinite;
}

@keyframes progressShine {
  0% {
    transform: translateX(-100%);
  }

  100% {
    transform: translateX(100%);
  }
}

/* Responsive Design */
@media (max-width: 768px) {
  body {
    padding: 10px;
  }

  .container {
    padding: 0.5rem;
  }

  h1 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
  }

  .logo-img {
    height: 35px;
  }

  .card {
    padding: 1rem;
  }

  .btn {
    padding: 0.75rem 1.25rem;
    font-size: 0.9375rem;
  }

  .session-code {
    font-size: 1.5rem;
    padding: 0.75rem;
  }

  .option-card {
    padding: 0.875rem 1rem;
  }

  .leaderboard-table tbody td {
    padding: 0.75rem;
    font-size: 0.875rem;
  }

  .rank-badge {
    width: 28px;
    height: 28px;
    font-size: 0.75rem;
  }
}

/* Loading Animation */
@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

.loading {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-radius: 50%;
  border-top-color: #fff;
  animation: spin 0.8s linear infinite;
}

/* Micro-interactions */
.btn,
.option-card,
.card {
  will-change: transform;
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}


/* Timer Display */
.timer-display {
  display: flex;
  justify-content: center;
  align-items: center;
  margin: 2rem 0;
  padding: 1rem;
}

.timer-ring {
  position: relative;
  width: 100px;
  height: 100px;
}

.timer-ring svg {
  transform: rotate(-90deg);
}

.timer-circle-bg {
  fill: none;
  stroke: var(--border-color);
  stroke-width: 6;
}

.timer-circle {
  fill: none;
  stroke: #10b981;
  stroke-width: 6;
  stroke-linecap: round;
  transition: stroke 0.3s ease, stroke-dashoffset 0.5s linear;
}

.timer-text {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 2rem;
  font-weight: 800;
  color: var(--text-primary);
}

.option-display {
  padding: 1rem;
  background: var(--background);
  border: 2px solid var(--border-color);
  border-radius: var(--radius);
  font-weight: 500;
  transition: var(--transition);
}

/* Reconnection Overlay */
.reconnect-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(5px);
  z-index: 9999;
  display: flex;
  justify-content: center;
  align-items: center;
  opacity: 1;
  transition: opacity 0.3s ease;
}

.reconnect-overlay.hidden {
  display: none !important;
  opacity: 0;
}

.reconnect-box {
  background: white;
  padding: 2rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  animation: slideInUp 0.3s ease-out;
}

.reconnect-box p {
  margin: 0;
  font-weight: 600;
  color: var(--text-main);
}

.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid rgba(102, 126, 234, 0.2);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}