/* ============================================================
   超级通讯平台 · 动效系统（A+ 新增）
   原则：克制、顺滑、不打扰。全部用变量时长，统一管理。
   ============================================================ */
:root { --t-fast: .16s; --t-base: .26s; --t-slow: .4s; --ease: cubic-bezier(.2,.8,.2,1); }

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
}

/* —— 换页：内容滑入淡入 —— */
@keyframes screenIn {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}
#screen > div { animation: screenIn var(--t-base) var(--ease) both; }
/* 整屏页（登录/通话/直播/短视频）用更轻的淡入，避免位移冲突 */
#screen > .login, #screen > .call, #screen > .shorts,
#screen > .onboard, #screen > .live { animation: fadeIn var(--t-base) var(--ease) both; }

@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

/* —— 点击回弹反馈 —— */
.list-item:active, .btn:active, .tab:active, .grid-entry:active,
.sheet-grid .si:active, .feed-card:active, .video-cell:active, .seg:active,
.cc:active, .si:active { transform: scale(.97); }
.list-item, .btn, .tab, .grid-entry, .feed-card, .video-cell, .seg, .cc { transition: transform var(--t-fast) var(--ease), background var(--t-fast) ease, color var(--t-fast) ease; }

/* —— Tab 切换激活时图标轻跳 —— */
@keyframes tabPop { 0% { transform: scale(1);} 50% { transform: scale(1.18);} 100% { transform: scale(1);} }
.tab.active .ti { animation: tabPop var(--t-base) var(--ease); }

/* —— 骨架屏微光 —— */
.skeleton { position: relative; overflow: hidden; background: var(--bg-card-2); border-radius: var(--r-sm); }
.skeleton::after {
  content: ""; position: absolute; inset: 0;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.06), transparent);
  transform: translateX(-100%); animation: shimmer 1.3s infinite;
}
@keyframes shimmer { 100% { transform: translateX(100%); } }
.sk-line { height: 12px; margin: 6px 0; }
.sk-line.w60 { width: 60%; } .sk-line.w40 { width: 40%; } .sk-line.w80 { width: 80%; }

/* —— 数字滚动入场 —— */
@keyframes numUp { from { opacity: 0; transform: translateY(6px);} to { opacity: 1; transform: translateY(0);} }
.num-anim { animation: numUp var(--t-slow) var(--ease) both; }

/* —— Toast 已有过渡；徽标轻微脉冲 —— */
@keyframes pulse { 0%,100% { transform: scale(1);} 50% { transform: scale(1.12);} }
.tab-badge { animation: pulse 2.4s ease-in-out infinite; }

/* —— 弹幕滚动 —— */
@keyframes danmu { from { transform: translateX(100%);} to { transform: translateX(-120%);} }