:root{--bg:#f5f6f8;--surface:#fff;--text:#283142;--muted:#758093;--line:#e3e8f0;--accent:#5a72e8;--soft:#edf0ff;--danger:#bf5266;--shadow:0 16px 44px rgba(39,49,70,.08)}*{box-sizing:border-box}body{margin:0;color:var(--text);background:var(--bg);font:15px/1.65 "PingFang SC","Microsoft YaHei",system-ui,sans-serif}a{color:inherit;text-decoration:none}.member-body{min-height:100vh}.member-shell{width:min(1120px,calc(100% - 40px));margin:auto}.member-topbar{height:82px;display:flex;align-items:center;justify-content:space-between}.member-brand{font:700 1.25rem Georgia,"Noto Serif SC",serif}.member-brand span{color:var(--accent)}.member-topbar nav{display:flex;align-items:center;gap:19px;color:var(--muted);font-size:.85rem}.member-topbar nav a:hover{color:var(--accent)}.member-topbar form{margin:0}.member-topbar button{border:0;background:none;color:var(--muted);cursor:pointer;font-size:.85rem}.mini-label{margin:0 0 10px;color:var(--accent);font-size:.69rem;font-weight:800;letter-spacing:.14em}.login-wrap{min-height:100vh;display:grid;place-items:center;padding:30px;background:radial-gradient(circle at 78% 14%,#dce5ff 0,transparent 26%),radial-gradient(circle at 15% 84%,#d9f1e9 0,transparent 25%),var(--bg)}.back-home{position:fixed;top:30px;left:40px;color:var(--muted);font-size:.85rem}.login-card{width:min(100%,440px);padding:44px;border:1px solid var(--line);border-radius:20px;background:var(--surface);box-shadow:var(--shadow)}.login-card h1,.chat-side h1,.file-intro h1{margin:0;font:500 2.5rem/1.2 Georgia,"Noto Serif SC",serif;letter-spacing:-.05em}.login-lead{margin:13px 0 29px;color:var(--muted)}.login-card label,.upload-card label{display:grid;gap:7px;margin-bottom:17px;font-size:.84rem;font-weight:700}.login-card input,.upload-card input{width:100%;padding:12px 13px;border:1px solid var(--line);border-radius:9px;outline:0;background:#fff}.login-card input:focus,.upload-card 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3px;color:#fff;background:#6178e4;font-size:.8rem;font-weight:800}.current-user b,.current-user small{display:block}.current-user small{color:#66758b;font-size:.73rem}.chat-panel{display:flex;flex-direction:column;min-width:0}.chat-head{display:flex;align-items:center;justify-content:space-between;padding:26px 30px;border-bottom:1px solid var(--line)}.chat-head h2,.upload-card h2,.file-list h2{margin:0;font:500 1.35rem Georgia,"Noto Serif SC",serif}.chat-head p{margin:4px 0 0;color:var(--muted);font-size:.76rem}.chat-head p i{display:inline-block;width:6px;height:6px;border-radius:50%;background:#58ba88}.chat-head>span{padding:5px 9px;border-radius:99px;color:var(--accent);background:var(--soft);font-size:.71rem;font-weight:800}.message-list{flex:1;min-height:350px;max-height:475px;padding:25px 30px;overflow:auto}.message{display:flex;gap:11px;margin-bottom:18px}.message.mine{flex-direction:row-reverse}.message.mine>div:last-child{align-items:flex-end}.message>div:last-child{display:flex;flex-direction:column;max-width:78%}.message-author{display:flex;gap:8px;align-items:baseline;font-size:.8rem}.message-author time{color:var(--muted);font-size:.7rem}.message p{margin:4px 0 0;padding:9px 12px;border-radius:4px 12px 12px;background:#f0f2f7}.message.mine p{color:white;background:var(--accent);border-radius:12px 4px 12px 12px}.empty-chat,.empty-files{padding:30px;text-align:center;color:var(--muted);font-size:.85rem}.chat-form{padding:17px 30px;border-top:1px solid var(--line)}.chat-form textarea{width:100%;resize:vertical;min-height:54px;max-height:150px;padding:10px;border:1px solid var(--line);border-radius:9px;outline:0}.chat-form textarea:focus{border-color:var(--accent)}.chat-form>div{display:flex;align-items:center;justify-content:space-between;margin-top:7px;color:var(--muted);font-size:.72rem}.chat-form button{width:auto;padding:7px 12px}.chat-form button b{font-size:1rem}.file-page{display:grid;grid-template-columns:.85fr 1.15fr;gap:20px;padding:30px 0 70px}.file-intro{padding:42px 37px;border-radius:20px;background:linear-gradient(145deg,#e8edff,#e4f8f1)}.file-intro p:not(.mini-label){color:#607187}.upload-card,.file-list{padding:28px;border:1px solid var(--line);border-radius:18px;background:var(--surface)}.upload-card h2{margin-bottom:21px}.upload-card>p{margin:13px 0 0;color:var(--muted);font-size:.74rem}.file-list{grid-column:span 2}.file-list-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:12px}.file-list-head span{color:var(--muted);font-size:.75rem}.file-list article{display:grid;grid-template-columns:44px 1fr auto auto;gap:15px;align-items:center;padding:14px 0;border-top:1px solid var(--line)}.file-icon{display:grid;place-items:center;width:38px;height:38px;border-radius:10px;color:var(--accent);background:var(--soft);font-size:.65rem;font-weight:800}.file-name b,.file-name small{display:block}.file-name small{color:var(--muted);font-size:.72rem}.file-list article>a{color:var(--accent);font-size:.82rem;font-weight:800}.file-list article form{margin:0}.file-list article button{padding:0;border:0;color:var(--danger);background:none;cursor:pointer;font-size:.8rem}@media(max-width:760px){.member-shell{width:min(100% - 28px,1120px)}.member-topbar{height:68px}.member-topbar nav{gap:10px}.chat-layout,.file-page{grid-template-columns:1fr}.chat-side{padding:29px}.chat-side h1{font-size:2rem}.current-user{margin-top:22px}.file-list{grid-column:auto}.file-list article{grid-template-columns:40px 1fr auto}.file-list article form{grid-column:3}.file-list article>a{grid-column:3;grid-row:1}.file-list article form{grid-row:2}.back-home{top:20px;left:22px}.login-card{padding:32px 25px;margin-top:30px}}
:root{--file-preview-fix:1}.file-list article{grid-template-columns:84px minmax(0,1fr) auto auto auto!important}.file-name{min-width:0}.file-name b{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.current-user>img,.message-avatar img{width:100%;height:100%;display:block;object-fit:cover}.current-user>img{width:37px;height:37px;border-radius:13px 13px 13px 3px}.message-avatar{width:37px!important;height:37px!important;min-width:37px;flex:0 0 37px;overflow:hidden}.message-avatar img{width:37px!important;height:37px!important;max-width:37px!important;max-height:37px!important;border-radius:13px 13px 13px 3px}.current-user>img{max-width:37px!important;max-height:37px!important;object-fit:cover!important}
/* Refined admin-only chat deletion control. */
.message-list .message>div:last-child>form{margin:5px 0 0;line-height:1}.message-list .message>div:last-child>form button{display:grid;place-items:center;width:22px;height:22px;padding:0;border:1px solid #e5c7cd;border-radius:50%;color:#b95565;background:#fff;cursor:pointer;font-size:0;opacity:.55;transition:.18s}.message-list .message>div:last-child>form button:before{content:"×";font-size:16px;line-height:1}.message-list .message>div:last-child>form button:hover{border-color:#b95565;background:#fff0f2;opacity:1;transform:scale(1.08)}