/* ========================================
   收藏页面专用样式 - 深度优化版
   ======================================== */

/* Banner标题居中优化 */
.theme-banner {
  text-align: center;
  padding: 80px 20px 60px;
}

.banner-title {
  text-align: center;
  margin: 0 auto;
}

.banner-subtitle {
  text-align: center;
  margin: 16px auto 0;
}

/* Banner装饰 */
.banner-decoration {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-top: 16px;
  opacity: 0.8;
}

.deco-star {
  font-size: 20px;
  color: rgba(247, 192, 92, 0.8);
  animation: starTwinkle 2s ease-in-out infinite;
  filter: drop-shadow(0 0 8px rgba(247, 192, 92, 0.6));
}

.deco-star:first-child {
  animation-delay: 0s;
}

.deco-star:last-child {
  animation-delay: 1s;
}

.deco-line {
  width: 80px;
  height: 2px;
  background: linear-gradient(90deg,
    transparent,
    rgba(247, 192, 92, 0.6),
    transparent);
  animation: lineExpand 2s ease-in-out infinite;
}

@keyframes starTwinkle {
  0%, 100% { opacity: 0.6; transform: scale(1) rotate(0deg); }
  50% { opacity: 1; transform: scale(1.2) rotate(180deg); }
}

@keyframes lineExpand {
  0%, 100% { width: 80px; opacity: 0.6; }
  50% { width: 120px; opacity: 1; }
}

/* 阅读进度条 */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 4px;
  background: linear-gradient(90deg, 
    rgba(247, 192, 92, 0.9), 
    rgba(247, 231, 173, 1),
    rgba(247, 192, 92, 0.9));
  box-shadow: 0 0 20px rgba(247, 192, 92, 0.8),
              0 0 40px rgba(247, 192, 92, 0.4);
  z-index: 9999;
  transition: width 0.1s ease-out;
  animation: progressPulse 2s ease-in-out infinite;
}

@keyframes progressPulse {
  0%, 100% { box-shadow: 0 0 20px rgba(247, 192, 92, 0.8), 0 0 40px rgba(247, 192, 92, 0.4); }
  50% { box-shadow: 0 0 30px rgba(247, 192, 92, 1), 0 0 60px rgba(247, 192, 92, 0.6); }
}

/* 收藏容器 */
.bookmarks-container {
  max-width: 900px;
  margin: 0 auto;
  padding: 40px 20px;
  position: relative;
}

/* 背景装饰粒子 */
.bookmarks-container::before {
  content: "";
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(circle at 20% 30%, rgba(247, 192, 92, 0.03) 0%, transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(247, 231, 173, 0.02) 0%, transparent 50%);
  pointer-events: none;
  z-index: -1;
  animation: particleFloat 20s ease-in-out infinite;
}

@keyframes particleFloat {
  0%, 100% { transform: translateY(0) scale(1); }
  50% { transform: translateY(-20px) scale(1.05); }
}

/* 页面头部统计 */
.bookmarks-header {
  margin-bottom: 48px;
  position: relative;
}

.stats-bar {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 20px;
  margin-bottom: 24px;
  position: relative;
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 28px 24px;
  background: linear-gradient(135deg, 
    rgba(247, 192, 92, 0.12),
    rgba(247, 192, 92, 0.06));
  border: 2px solid transparent;
  border-radius: 20px;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
  backdrop-filter: blur(10px);
}

/* 卡片光泽效果 */
.stat-item::before {
  content: "";
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(
    45deg,
    transparent,
    rgba(247, 192, 92, 0.1),
    transparent
  );
  transform: rotate(45deg);
  transition: all 0.6s ease;
}

.stat-item:hover::before {
  left: 100%;
}

/* 边框渐变动画 */
.stat-item::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 20px;
  padding: 2px;
  background: linear-gradient(135deg, 
    rgba(247, 192, 92, 0.4),
    rgba(247, 231, 173, 0.2),
    rgba(247, 192, 92, 0.4));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, 
                linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0;
  transition: opacity 0.4s ease;
}

.stat-item:hover {
  background: linear-gradient(135deg, 
    rgba(247, 192, 92, 0.2),
    rgba(247, 192, 92, 0.1));
  transform: translateY(-8px) scale(1.02);
  box-shadow: 
    0 12px 40px rgba(247, 192, 92, 0.25),
    0 0 60px rgba(247, 192, 92, 0.15),
    inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

.stat-item:hover::after {
  opacity: 1;
}

.stat-number {
  font-size: 42px;
  font-weight: 700;
  font-family: var(--font-heading, "Cinzel", serif);
  color: rgba(247, 231, 173, 0.98);
  margin-bottom: 8px;
  text-shadow: 
    0 0 30px rgba(247, 192, 92, 0.6),
    0 0 60px rgba(247, 192, 92, 0.3),
    0 2px 4px rgba(0, 0, 0, 0.5);
  position: relative;
  z-index: 1;
  transition: all 0.4s ease;
  background: linear-gradient(135deg, 
    rgba(247, 231, 173, 1),
    rgba(247, 192, 92, 0.9));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-item:hover .stat-number {
  transform: scale(1.15);
  filter: brightness(1.2);
}

.stat-label {
  font-size: 13px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.7);
  position: relative;
  z-index: 1;
  font-weight: 500;
}

/* 操作按钮栏 */
.actions-bar {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.action-btn {
  padding: 14px 32px;
  background: linear-gradient(135deg,
    rgba(247, 192, 92, 0.2),
    rgba(247, 192, 92, 0.1));
  border: 2px solid rgba(247, 192, 92, 0.5);
  border-radius: 999px;
  color: rgba(247, 231, 173, 0.98);
  font-size: 14px;
  letter-spacing: 0.1em;
  cursor: pointer;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  font-family: var(--font-body, "Open Sans", sans-serif);
  font-weight: 600;
  position: relative;
  overflow: hidden;
  backdrop-filter: blur(8px);
  text-transform: uppercase;
}

/* 按钮光波效果 */
.action-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 ease, height 0.6s ease;
}

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

.action-btn:hover {
  background: linear-gradient(135deg,
    rgba(247, 192, 92, 0.35),
    rgba(247, 192, 92, 0.2));
  border-color: rgba(247, 192, 92, 0.8);
  transform: translateY(-3px);
  box-shadow: 
    0 8px 24px rgba(247, 192, 92, 0.4),
    0 0 40px rgba(247, 192, 92, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.2);
}

.action-btn:active {
  transform: translateY(-1px);
}

.action-btn.danger {
  background: linear-gradient(135deg,
    rgba(220, 38, 38, 0.2),
    rgba(220, 38, 38, 0.1));
  border-color: rgba(220, 38, 38, 0.5);
  color: rgba(252, 165, 165, 0.98);
}

.action-btn.danger:hover {
  background: linear-gradient(135deg,
    rgba(220, 38, 38, 0.35),
    rgba(220, 38, 38, 0.2));
  border-color: rgba(220, 38, 38, 0.8);
  box-shadow: 
    0 8px 24px rgba(220, 38, 38, 0.4),
    0 0 40px rgba(220, 38, 38, 0.2);
}

/* 收藏列表 */
.bookmarks-list {
  display: flex;
  flex-direction: column;
  gap: 40px;
}

/* 页面分组 */
.bookmark-group {
  position: relative;
  padding: 36px;
  background: linear-gradient(135deg,
    rgba(26, 20, 16, 0.5),
    rgba(6, 7, 10, 0.4));
  border: 2px solid rgba(247, 192, 92, 0.3);
  border-radius: 24px;
  overflow: hidden;
  backdrop-filter: blur(10px);
  box-shadow: 
    0 8px 32px rgba(0, 0, 0, 0.3),
    inset 0 1px 0 rgba(255, 255, 255, 0.05);
  transition: all 0.4s ease;
}

.bookmark-group:hover {
  border-color: rgba(247, 192, 92, 0.5);
  box-shadow: 
    0 12px 48px rgba(0, 0, 0, 0.4),
    0 0 60px rgba(247, 192, 92, 0.1),
    inset 0 1px 0 rgba(255, 255, 255, 0.08);
  transform: translateY(-4px);
}

/* 顶部装饰条 */
.bookmark-group::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 5px;
  background: linear-gradient(90deg,
    transparent,
    rgba(247, 192, 92, 0.8) 20%,
    rgba(247, 231, 173, 0.9) 50%,
    rgba(247, 192, 92, 0.8) 80%,
    transparent);
  animation: borderFlow 3s ease-in-out infinite;
}

@keyframes borderFlow {
  0%, 100% { opacity: 0.6; transform: translateX(-10%); }
  50% { opacity: 1; transform: translateX(10%); }
}

/* 分组标题 */
.group-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 28px;
  padding-bottom: 20px;
  border-bottom: 2px solid rgba(247, 192, 92, 0.2);
  position: relative;
}

/* 标题下方光晕 */
.group-header::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 100px;
  height: 2px;
  background: linear-gradient(90deg,
    rgba(247, 192, 92, 0.9),
    transparent);
  animation: headerGlow 2s ease-in-out infinite;
}

@keyframes headerGlow {
  0%, 100% { width: 100px; opacity: 0.7; }
  50% { width: 200px; opacity: 1; }
}

.group-title {
  font-family: var(--font-heading, "Cinzel", serif);
  font-size: 26px;
  letter-spacing: 0.1em;
  color: rgba(247, 231, 173, 0.98);
  margin: 0;
  display: flex;
  align-items: center;
  gap: 16px;
  font-weight: 600;
  text-shadow: 
    0 0 20px rgba(247, 192, 92, 0.5),
    0 2px 4px rgba(0, 0, 0, 0.6);
}

.group-icon {
  font-size: 32px;
  filter: drop-shadow(0 0 12px rgba(247, 192, 92, 0.6))
          drop-shadow(0 4px 8px rgba(0, 0, 0, 0.5));
  animation: iconFloat 3s ease-in-out infinite;
}

@keyframes iconFloat {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-5px) rotate(-5deg); }
}

.group-count {
  font-size: 15px;
  color: rgba(255, 255, 255, 0.5);
  font-weight: 400;
  margin-left: 8px;
  padding: 4px 12px;
  background: rgba(247, 192, 92, 0.15);
  border-radius: 999px;
  border: 1px solid rgba(247, 192, 92, 0.3);
}

.clear-group-btn {
  padding: 10px 20px;
  background: rgba(220, 38, 38, 0.15);
  border: 2px solid rgba(220, 38, 38, 0.4);
  border-radius: 999px;
  color: rgba(252, 165, 165, 0.9);
  font-size: 13px;
  cursor: pointer;
  transition: all 0.3s ease;
  font-weight: 600;
  letter-spacing: 0.05em;
}

.clear-group-btn:hover {
  background: rgba(220, 38, 38, 0.25);
  border-color: rgba(220, 38, 38, 0.7);
  transform: scale(1.05);
  box-shadow: 0 4px 16px rgba(220, 38, 38, 0.3);
}

/* 收藏项 */
.bookmark-item {
  position: relative;
  padding: 24px 28px;
  margin-bottom: 20px;
  background: linear-gradient(120deg,
    rgba(247, 192, 92, 0.1),
    transparent 40%);
  border-left: 4px solid rgba(247, 192, 92, 0.5);
  border-radius: 12px;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  overflow: hidden;
}

/* 收藏项背景光效 */
.bookmark-item::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg,
    transparent,
    rgba(247, 192, 92, 0.15),
    transparent);
  transition: left 0.6s ease;
}

.bookmark-item:hover::before {
  left: 100%;
}

/* 右侧装饰边框 */
.bookmark-item::after {
  content: "";
  position: absolute;
  top: 50%;
  right: 0;
  transform: translateY(-50%);
  width: 3px;
  height: 0;
  background: linear-gradient(180deg,
    transparent,
    rgba(247, 192, 92, 0.6),
    transparent);
  border-radius: 999px;
  transition: height 0.4s ease;
}

.bookmark-item:hover::after {
  height: 80%;
}

.bookmark-item:last-child {
  margin-bottom: 0;
}

.bookmark-item:hover {
  background: linear-gradient(120deg,
    rgba(247, 192, 92, 0.18),
    transparent 50%);
  border-left-color: rgba(247, 192, 92, 0.9);
  transform: translateX(12px);
  box-shadow: 
    -4px 0 0 rgba(247, 192, 92, 0.4),
    0 4px 20px rgba(247, 192, 92, 0.15),
    inset 0 1px 0 rgba(255, 255, 255, 0.05);
}

.bookmark-content {
  color: rgba(255, 255, 255, 0.95);
  line-height: 2.2;
  font-size: 16px;
  letter-spacing: 0.04em;
  margin: 0 0 16px 0;
  position: relative;
  z-index: 1;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

/* 首字放大装饰 */
.bookmark-content::first-letter {
  font-size: 1.8em;
  font-weight: 700;
  color: rgba(247, 192, 92, 0.9);
  float: left;
  margin-right: 8px;
  line-height: 1;
  text-shadow: 0 0 10px rgba(247, 192, 92, 0.5);
}

.bookmark-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  position: relative;
  z-index: 1;
}

.bookmark-source {
  font-size: 13px;
  color: rgba(247, 192, 92, 0.7);
  letter-spacing: 0.08em;
  padding: 4px 12px;
  background: rgba(247, 192, 92, 0.08);
  border-radius: 999px;
  border: 1px solid rgba(247, 192, 92, 0.2);
}

.bookmark-actions {
  display: flex;
  gap: 10px;
}

.mini-btn {
  padding: 8px 18px;
  background: rgba(247, 192, 92, 0.15);
  border: 1px solid rgba(247, 192, 92, 0.4);
  border-radius: 999px;
  color: rgba(247, 231, 173, 0.9);
  font-size: 12px;
  cursor: pointer;
  transition: all 0.3s ease;
  text-decoration: none;
  font-weight: 500;
  letter-spacing: 0.05em;
  position: relative;
  overflow: hidden;
}

.mini-btn::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  background: rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  transform: translate(-50%, -50%);
  transition: width 0.4s ease, height 0.4s ease;
}

.mini-btn:hover::before {
  width: 150px;
  height: 150px;
}

.mini-btn:hover {
  background: rgba(247, 192, 92, 0.25);
  border-color: rgba(247, 192, 92, 0.6);
  color: rgba(247, 231, 173, 1);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(247, 192, 92, 0.3);
}

.mini-btn.remove {
  background: rgba(220, 38, 38, 0.15);
  border-color: rgba(220, 38, 38, 0.4);
  color: rgba(252, 165, 165, 0.9);
}

.mini-btn.remove:hover {
  background: rgba(220, 38, 38, 0.25);
  border-color: rgba(220, 38, 38, 0.6);
  box-shadow: 0 4px 12px rgba(220, 38, 38, 0.3);
}

/* 空状态 */
.empty-state {
  text-align: center;
  padding: 100px 20px;
  color: rgba(255, 255, 255, 0.6);
  position: relative;
}

/* 空状态背景动画 */
.empty-state::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 300px;
  height: 300px;
  background: radial-gradient(circle,
    rgba(247, 192, 92, 0.05) 0%,
    transparent 70%);
  animation: emptyPulse 3s ease-in-out infinite;
}

@keyframes emptyPulse {
  0%, 100% { transform: translate(-50%, -50%) scale(1); opacity: 0.5; }
  50% { transform: translate(-50%, -50%) scale(1.2); opacity: 0.8; }
}

.empty-icon {
  font-size: 100px;
  margin-bottom: 32px;
  opacity: 0.5;
  filter: drop-shadow(0 0 20px rgba(247, 192, 92, 0.3));
  animation: iconBounce 2s ease-in-out infinite;
  position: relative;
  z-index: 1;
}

@keyframes iconBounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

.empty-state h3 {
  font-family: var(--font-heading, "Cinzel", serif);
  font-size: 28px;
  color: rgba(247, 231, 173, 0.9);
  margin: 0 0 16px 0;
  letter-spacing: 0.08em;
  text-shadow: 0 0 20px rgba(247, 192, 92, 0.4);
  position: relative;
  z-index: 1;
}

.empty-state p {
  font-size: 17px;
  margin: 0 0 40px 0;
  line-height: 2;
  color: rgba(255, 255, 255, 0.6);
  position: relative;
  z-index: 1;
}

.cta-link {
  display: inline-block;
  padding: 16px 40px;
  background: linear-gradient(135deg,
    rgba(247, 192, 92, 0.3),
    rgba(247, 192, 92, 0.2));
  border: 2px solid rgba(247, 192, 92, 0.6);
  border-radius: 999px;
  color: rgba(247, 231, 173, 0.98);
  text-decoration: none;
  font-size: 16px;
  letter-spacing: 0.1em;
  transition: all 0.4s ease;
  font-weight: 600;
  position: relative;
  z-index: 1;
  overflow: hidden;
}

.cta-link::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  background: rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  transform: translate(-50%, -50%);
  transition: width 0.6s ease, height 0.6s ease;
}

.cta-link:hover::before {
  width: 400px;
  height: 400px;
}

.cta-link:hover {
  background: linear-gradient(135deg,
    rgba(247, 192, 92, 0.4),
    rgba(247, 192, 92, 0.3));
  border-color: rgba(247, 192, 92, 0.9);
  transform: translateY(-3px);
  box-shadow: 
    0 12px 32px rgba(247, 192, 92, 0.4),
    0 0 60px rgba(247, 192, 92, 0.2);
}

/* Toast通知 - 增强版 */
.toast-notification {
  position: fixed;
  bottom: 100px;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  padding: 16px 32px;
  background: linear-gradient(135deg,
    rgba(6, 7, 10, 0.95),
    rgba(26, 20, 16, 0.95));
  border: 2px solid rgba(247, 192, 92, 0.7);
  border-radius: 999px;
  color: rgba(247, 231, 173, 0.98);
  font-size: 15px;
  letter-spacing: 0.1em;
  box-shadow: 
    0 12px 40px rgba(0, 0, 0, 0.6),
    0 0 60px rgba(247, 192, 92, 0.3),
    inset 0 1px 0 rgba(255, 255, 255, 0.1);
  z-index: 10000;
  opacity: 0;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  pointer-events: none;
  backdrop-filter: blur(10px);
  font-weight: 600;
}

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

/* 响应式 */
@media (max-width: 768px) {
  .bookmarks-container {
    padding: 24px 16px;
  }

  .stats-bar {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

  .stat-item {
    padding: 20px 16px;
  }

  .stat-number {
    font-size: 36px;
  }

  .stat-label {
    font-size: 12px;
  }

  .bookmark-group {
    padding: 24px 20px;
  }

  .group-title {
    font-size: 20px;
  }

  .group-icon {
    font-size: 26px;
  }

  .bookmark-item {
    padding: 20px;
  }

  .bookmark-content {
    font-size: 15px;
    line-height: 2;
  }

  .bookmark-meta {
    flex-direction: column;
    align-items: flex-start;
  }
  
  .bookmark-actions {
    width: 100%;
    justify-content: flex-start;
  }
}

@media (max-width: 480px) {
  .actions-bar {
    flex-direction: column;
  }

  .action-btn {
    width: 100%;
  }

  .stats-bar {
    grid-template-columns: 1fr;
  }
  
  .group-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
  
  .clear-group-btn {
    align-self: stretch;
  }
}

/* 渐进淡入动画 - 增强版 */
@keyframes slideInUp {
  from {
    opacity: 0;
    transform: translateY(40px) scale(0.95);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

.bookmark-group {
  animation: slideInUp 0.6s cubic-bezier(0.4, 0, 0.2, 1) backwards;
}

.bookmark-group:nth-child(1) { animation-delay: 0.1s; }
.bookmark-group:nth-child(2) { animation-delay: 0.2s; }
.bookmark-group:nth-child(3) { animation-delay: 0.3s; }

/* 收藏项淡入动画 */
@keyframes itemFadeIn {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.bookmark-item {
  animation: itemFadeIn 0.4s ease backwards;
}

.bookmark-item:nth-child(1) { animation-delay: 0.05s; }
.bookmark-item:nth-child(2) { animation-delay: 0.1s; }
.bookmark-item:nth-child(3) { animation-delay: 0.15s; }
.bookmark-item:nth-child(4) { animation-delay: 0.2s; }
.bookmark-item:nth-child(5) { animation-delay: 0.25s; }

/* 减少动画效果(系统偏好设置) */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* 打印样式 */
@media print {
  .reading-progress,
  .actions-bar,
  .clear-group-btn,
  .bookmark-actions {
    display: none !important;
  }
  
  .bookmark-group {
    page-break-inside: avoid;
    border: 1px solid #ccc;
  }
  
  .bookmark-item {
    page-break-inside: avoid;
  }
}

/* 回到顶部按钮 */
.back-to-top {
  position: fixed;
  bottom: 40px;
  right: 40px;
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg,
    rgba(247, 192, 92, 0.3),
    rgba(247, 192, 92, 0.2));
  border: 2px solid rgba(247, 192, 92, 0.6);
  border-radius: 50%;
  color: rgba(247, 231, 173, 0.95);
  font-size: 24px;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  z-index: 1000;
  backdrop-filter: blur(10px);
  box-shadow: 
    0 8px 24px rgba(0, 0, 0, 0.3),
    0 0 40px rgba(247, 192, 92, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background: linear-gradient(135deg,
    rgba(247, 192, 92, 0.5),
    rgba(247, 192, 92, 0.3));
  border-color: rgba(247, 192, 92, 0.9);
  transform: translateY(-4px) scale(1.05);
  box-shadow: 
    0 12px 32px rgba(0, 0, 0, 0.4),
    0 0 60px rgba(247, 192, 92, 0.4);
}

.back-to-top:active {
  transform: translateY(-2px) scale(1);
}

.arrow-up {
  animation: arrowBounce 1.5s ease-in-out infinite;
}

@keyframes arrowBounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-4px); }
}

@media (max-width: 768px) {
  .back-to-top {
    bottom: 24px;
    right: 24px;
    width: 48px;
    height: 48px;
    font-size: 20px;
  }
}