/* 备考指南留言板 + 流星弹幕 —— 贴合站点 SSR 设计语言（#1d1d1f / #0071e3 / 8px 体系） */
#yyzt-comments{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;color:#1d1d1f}
.bc-fab{position:fixed;right:18px;bottom:18px;z-index:2147483100;display:inline-flex;align-items:center;gap:8px;min-height:52px;padding:0 18px;border:0;border-radius:18px;background:#1d1d1f;color:#fff;font:600 14px/1 -apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC",sans-serif;cursor:pointer;box-shadow:0 10px 30px rgb(0 0 0 / 22%);transition:transform 150ms cubic-bezier(.16,1,.3,1),background 150ms ease}
.bc-fab:hover{background:#26262b;transform:translateY(-2px)}
.bc-fab:active{transform:translateY(0)}
.bc-fab:focus-visible{outline:2px solid #0071e3;outline-offset:3px}
.bc-fab .bc-fab-icon{display:inline-flex}
.bc-fab .bc-fab-dot{width:7px;height:7px;border-radius:50%;background:#30d158;box-shadow:0 0 0 3px rgb(48 209 88 / 22%)}
.bc-fab.bc-fab--open{background:#0071e3}
.bc-fab.bc-fab--open:hover{background:#0a6fd8}

.bc-panel{position:fixed;right:18px;bottom:82px;z-index:2147483050;display:flex;flex-direction:column;width:min(384px,calc(100vw - 24px));max-height:min(72vh,600px);background:#fff;border:1px solid rgb(0 0 0 / 8%);border-radius:20px;box-shadow:0 24px 64px rgb(0 0 0 / 16%),0 2px 8px rgb(0 0 0 / 6%);overflow:hidden;transform-origin:100% 100%;animation:bcIn 220ms cubic-bezier(.16,1,.3,1)}
@keyframes bcIn{from{opacity:0;transform:translateY(14px) scale(.97)}to{opacity:1;transform:none}}
.bc-panel.bc-panel--hiding{animation:bcOut 160ms ease forwards}
@keyframes bcOut{to{opacity:0;transform:translateY(10px) scale(.98)}}
.bc-head{display:flex;align-items:center;gap:8px;padding:14px 16px 12px;border-bottom:1px solid rgb(0 0 0 / 6%)}
.bc-head h4{margin:0;font-size:15px;font-weight:800;letter-spacing:.01em}
.bc-head small{display:block;color:#86868b;font-size:11px;font-weight:400;margin-top:1px}
.bc-head-actions{margin-left:auto;display:flex;gap:4px}
.bc-head-actions button{display:inline-flex;align-items:center;justify-content:center;width:30px;height:30px;border:0;border-radius:9px;background:transparent;color:#6e6e73;cursor:pointer;transition:background 120ms ease,color 120ms ease}
.bc-head-actions button:hover{background:#f2f2f4;color:#1d1d1f}
.bc-head-actions button:focus-visible{outline:2px solid #0071e3;outline-offset:1px}
.bc-body{display:flex;flex-direction:column;min-height:180px;flex:1;overflow:hidden}
.bc-list{flex:1;overflow-y:auto;overscroll-behavior:contain;padding:10px 14px 4px}
.bc-msg{display:flex;gap:10px;padding:9px 0;animation:bcItem 200ms cubic-bezier(.16,1,.3,1)}
@keyframes bcItem{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:none}}
.bc-avatar{flex:none;display:grid;place-items:center;width:30px;height:30px;border-radius:50%;background:#eef2f7;color:#4b5563;font-size:12px;font-weight:800;margin-top:2px}
.bc-msg-main{min-width:0;flex:1}
.bc-msg-top{display:flex;align-items:baseline;gap:8px}
.bc-msg-nick{font-size:12.5px;font-weight:700;color:#1d1d1f;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.bc-msg-nick.bc-me{color:#0071e3}
.bc-msg-time{flex:none;color:#a1a1a6;font-size:10.5px}
.bc-msg-text{margin-top:3px;font-size:13.5px;line-height:1.65;color:#3a3a3c;overflow-wrap:anywhere;white-space:pre-wrap}
.bc-empty{display:grid;place-items:center;gap:8px;padding:30px 16px;text-align:center;color:#86868b}
.bc-empty svg{opacity:.55}
.bc-empty strong{color:#5b5b5e;font-size:13.5px}
.bc-empty p{margin:0;font-size:12.5px;line-height:1.7}

.bc-form{border-top:1px solid rgb(0 0 0 / 6%);padding:12px 14px 14px;background:#fdfdfe}
.bc-login{display:grid;gap:10px;padding:2px 0}
.bc-login p{margin:0;color:#6e6e73;font-size:13px;line-height:1.7}
.bc-login a{display:inline-flex;align-items:center;justify-content:center;min-height:42px;border-radius:13px;background:#0071e3;color:#fff;font-size:13.5px;font-weight:700;transition:background 150ms ease}
.bc-login a:hover{background:#0a6fd8}
.bc-login a:focus-visible{outline:2px solid #0071e3;outline-offset:2px}
.bc-text{width:100%;min-height:68px;max-height:160px;padding:10px 12px;border:1px solid rgb(0 0 0 / 14%);border-radius:13px;background:#fff;font:400 13.5px/1.6 inherit;color:#1d1d1f;resize:vertical;transition:border-color 120ms ease,box-shadow 120ms ease}
.bc-text:focus{outline:none;border-color:#0071e3;box-shadow:0 0 0 3px rgb(0 113 227 / 16%)}
.bc-text::placeholder{color:#a1a1a6}
.bc-meta{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-top:7px;color:#a1a1a6;font-size:11px}
.bc-flag{color:#d9534f;font-size:12px;min-height:16px}
.bc-captcha{display:flex;align-items:center;gap:9px;margin-top:9px}
.bc-captcha-img{flex:none;width:118px;height:42px;padding:0;border:1px solid rgb(0 0 0 / 12%);border-radius:10px;background:#fff;cursor:pointer;overflow:hidden;display:inline-flex;align-items:center;justify-content:center}
.bc-captcha-img img{width:100%;height:100%;display:block}
.bc-captcha-img span{font-size:11px;color:#86868b;padding:0 4px}
.bc-captcha-input{flex:1;min-width:0;height:42px;padding:0 11px;border:1px solid rgb(0 0 0 / 14%);border-radius:10px;font:400 13.5px inherit;color:#1d1d1f}
.bc-captcha-input:focus{outline:none;border-color:#0071e3;box-shadow:0 0 0 3px rgb(0 113 227 / 16%)}
.bc-submit{display:inline-flex;align-items:center;justify-content:center;min-height:42px;margin-top:10px;padding:0 16px;width:100%;border:0;border-radius:13px;background:#1d1d1f;color:#fff;font-size:13.5px;font-weight:700;cursor:pointer;transition:background 150ms ease,opacity 150ms ease}
.bc-submit:hover{background:#26262b}
.bc-submit:disabled{opacity:.55;cursor:default}
.bc-submit:focus-visible{outline:2px solid #0071e3;outline-offset:2px}
.bc-error{margin:8px 2px 0;color:#d9534f;font-size:12.5px;line-height:1.6}
.bc-error[hidden]{display:none}
.bc-ok{display:inline-flex;align-items:center;gap:6px;margin:8px 2px 0;color:#1d9e75;font-size:12.5px}

/* 流星弹幕：左 → 右 拖尾横穿，玻璃字条 + 彗尾光 */
.bc-stage{position:fixed;inset:0;z-index:2147482900;pointer-events:none;overflow:hidden}
.bc-meteor{position:absolute;left:0;top:var(--y,10%);display:flex;align-items:center;gap:6px;will-change:transform;opacity:0}
.bc-meteor-tail{flex:none;width:88px;height:30px;background:linear-gradient(to left,rgba(0,113,227,.38),rgba(0,113,227,.06) 55%,transparent);border-radius:999px;filter:blur(1.5px);transform:scaleX(-1);margin-right:-4px}
.bc-meteor-card{display:flex;align-items:center;gap:9px;padding:9px 15px;border-radius:999px;background:rgb(255 255 255 / 92%);border:1px solid rgb(0 0 0 / 9%);box-shadow:0 4px 18px rgb(0 0 0 / 12%),0 0 22px rgb(0 113 227 / 16%);backdrop-filter:blur(6px)}
.bc-meteor-card .bc-m-nick{font-size:11.5px;font-weight:800;color:#0071e3;white-space:nowrap}
.bc-meteor-card .bc-m-nick.bc-m-me{color:#d85a30}
.bc-meteor-card .bc-m-text{font-size:13px;color:#1d1d1f;line-height:1.4;white-space:nowrap;max-width:min(56vw,520px);overflow:hidden;text-overflow:ellipsis}
.bc-meteor-card .bc-m-own{flex:none;font-size:10px;font-weight:800;color:#fff;background:#d85a30;border-radius:999px;padding:2px 7px}
@keyframes bcFly{0%{transform:translate3d(-120%,0,0);opacity:0}6%{opacity:1}92%{opacity:1}100%{transform:translate3d(calc(100vw + 60%),0,0);opacity:0}}
.bc-meteor.bc-run{animation-name:bcFly;animation-timing-function:linear;animation-fill-mode:both}

@media (max-width:480px){
  .bc-fab{right:14px;bottom:14px;min-height:48px;padding:0 15px;border-radius:16px}
  .bc-panel{right:12px;bottom:74px;width:calc(100vw - 24px);max-height:74vh}
  .bc-meteor-card .bc-m-text{max-width:46vw}
}
@media (prefers-reduced-motion:reduce){
  .bc-meteor{display:none}
  .bc-panel{animation:none}
}

/* HTML5 [hidden] 属性兜底：覆盖 .bc-captcha{display:flex} 等显式 display 规则 */
[hidden]{display:none!important}

/* ===== 面板内嵌登录 / 注册（本页完成，成功后自动刷新）===== */
.bc-login{display:grid;gap:12px;padding:12px 14px 14px;background:#fdfdfe;border-top:1px solid rgb(0 0 0 / 6%)}
.bc-seg{display:inline-flex;gap:4px;padding:3px;border-radius:11px;background:#f2f2f4;width:100%}
.bc-seg button{flex:1;min-height:34px;border:0;border-radius:9px;background:transparent;color:#5b5b5e;font-size:13px;font-weight:700;cursor:pointer;transition:background 150ms ease,color 150ms ease}
.bc-seg button.active{background:#fff;color:#1d1d1f;box-shadow:0 1px 4px rgb(0 0 0 / 10%)}
.bc-seg button:focus-visible{outline:2px solid #0071e3;outline-offset:1px}
.bc-auth-form{display:grid;gap:10px}
.bc-field{display:grid;gap:5px;margin:0}
.bc-field[hidden]{display:none}
.bc-field-label{color:#5b5b5e;font-size:12px;font-weight:600}
.bc-input{width:100%;min-width:0;height:42px;padding:0 12px;border:1px solid rgb(0 0 0 / 14%);border-radius:11px;background:#fff;font:400 13.5px inherit;color:#1d1d1f;transition:border-color 120ms ease,box-shadow 120ms ease}
.bc-input:focus{outline:none;border-color:#0071e3;box-shadow:0 0 0 3px rgb(0 113 227 / 16%)}
.bc-input::placeholder{color:#a1a1a6}
.bc-pwd-wrap{position:relative;display:flex;align-items:center}
.bc-pwd-wrap .bc-input{padding-right:40px}
.bc-eye{position:absolute;right:4px;display:inline-flex;align-items:center;justify-content:center;width:32px;height:32px;border:0;border-radius:8px;background:transparent;color:#8a939c;cursor:pointer;transition:color 120ms ease}
.bc-eye:hover{color:#0071e3}
.bc-eye:focus-visible{outline:2px solid #0071e3;outline-offset:1px}
.bc-login .bc-error{margin:0 2px}
.bc-login .bc-submit{margin-top:2px}
.bc-login .bc-captcha{margin-top:0}