/* ===== 互动增强样式 ===== */

/* 阅读进度条 */
.reading-progress{position:fixed;top:0;left:0;height:3px;background:linear-gradient(90deg,#38b572,#2fa363);z-index:9999;width:0;transition:width .1s;box-shadow:0 0 6px rgba(56,181,114,.4)}

/* 返回顶部 */
.back-to-top{position:fixed;right:16px;bottom:80px;width:42px;height:42px;border-radius:50%;background:#fff;border:1px solid #e8e8e8;box-shadow:0 2px 12px rgba(0,0,0,.1);display:flex;align-items:center;justify-content:center;cursor:pointer;opacity:0;visibility:hidden;transition:all .3s;z-index:998;color:#38b572}
.back-to-top.show{opacity:1;visibility:visible}
.back-to-top:hover{background:#38b572;color:#fff;border-color:#38b572;transform:translateY(-2px)}
.back-to-top:active{transform:translateY(0)}
@media(max-width:768px){
    .back-to-top{right:12px;bottom:72px;width:38px;height:38px}
}

/* 阅读时长 */
.meta-read-time{color:#38b572;font-weight:500}

/* 图片放大遮罩 */
.img-lightbox{position:fixed;top:0;left:0;width:100%;height:100%;background:rgba(0,0,0,.85);z-index:10000;display:flex;align-items:center;justify-content:center;opacity:0;visibility:hidden;transition:opacity .25s;cursor:zoom-out}
.img-lightbox.show{opacity:1;visibility:visible}
.img-lightbox img{max-width:92%;max-height:92%;border-radius:4px;box-shadow:0 8px 40px rgba(0,0,0,.5);transform:scale(.9);transition:transform .25s}
.img-lightbox.show img{transform:scale(1)}

/* 文章内图片可点击光标 */
.article-content img{cursor:zoom-in}

/* 读完提示条 */
.read-complete-bar{position:fixed;bottom:0;left:0;right:0;background:linear-gradient(135deg,#38b572,#2fa363);color:#fff;text-align:center;padding:10px 16px;font-size:.88rem;z-index:997;transform:translateY(100%);transition:transform .4s ease;box-shadow:0 -2px 12px rgba(56,181,114,.2)}
.read-complete-bar.show{transform:translateY(0)}
.read-complete-bar a{color:#fff;font-weight:700;text-decoration:underline;margin-left:6px}
.read-complete-bar .rc-close{position:absolute;right:12px;top:50%;transform:translateY(-50%);background:none;border:none;color:rgba(255,255,255,.7);font-size:1.2rem;cursor:pointer;padding:4px 8px;line-height:1}
.read-complete-bar .rc-close:hover{color:#fff}

/* 随机问答按钮 */
.random-qa-btn{display:inline-flex;align-items:center;gap:6px;padding:8px 16px;background:#f0faf5;color:#38b572;border:1px solid #d4ede0;border-radius:8px;font-size:.85rem;font-weight:500;cursor:pointer;transition:all .2s;text-decoration:none}
.random-qa-btn:hover{background:#38b572;color:#fff;border-color:#38b572}
.random-qa-btn:active{transform:scale(.97)}
.random-qa-btn svg{transition:transform .4s}
.random-qa-btn:hover svg{transform:rotate(180deg)}

/* 问答详情页投票动画 */
.qa-vote-btn{position:relative;overflow:hidden}
.vote-burst{position:absolute;pointer-events:none;font-size:1.2rem;animation:burstUp .8s ease-out forwards;left:50%;top:50%}
@keyframes burstUp{
    0%{opacity:1;transform:translate(-50%,-50%) scale(.5)}
    100%{opacity:0;transform:translate(-50%,-180%) scale(1.4)}
}
.qa-vote-btn.voted{background:#38b572;color:#fff;border-color:#38b572}
.qa-vote-btn.voted-down{background:#f59e0b;color:#fff;border-color:#f59e0b}

/* 列表卡片进入动画 */
.fade-in-up{opacity:0;transform:translateY(16px);transition:opacity .5s,transform .5s}
.fade-in-up.visible{opacity:1;transform:translateY(0)}