:root{--brand: #0FB39A;--brand-600: #0D9488;--brand-700: #0F766E;--brand-800: #115E56;--bubble-out: #D6F5EC;--bubble-in: #ffffff;--bg-app: #eef1f4;--bg-sidebar: #ffffff;--bg-panel: #ffffff;--bg-chat: #e9eef0;--bg-hover: #f3f5f7;--bg-selected: #e6f7f3;--text: #111b21;--text-muted: #667781;--text-soft: #8696a0;--border: #e5e9ec;--shadow-sm: 0 1px 2px rgba(11, 20, 26, .06);--shadow-md: 0 8px 24px rgba(11, 20, 26, .08);--radius: 14px}*{box-sizing:border-box}body{font-family:Segoe UI,system-ui,-apple-system,Roboto,Helvetica,Arial,sans-serif;margin:0;background:var(--bg-app);color:var(--text);-webkit-font-smoothing:antialiased}.app{display:flex;height:100vh;overflow:hidden;max-width:1600px;margin:0 auto;background:var(--bg-chat)}.sidebar{width:30%;min-width:320px;max-width:460px;background:var(--bg-sidebar);border-right:1px solid var(--border);display:flex;flex-direction:column}.app-bar{display:flex;align-items:center;justify-content:space-between;padding:14px 16px;background:linear-gradient(135deg,var(--brand-700),var(--brand-600));color:#fff}.app-bar-brand{display:flex;align-items:center;gap:10px}.app-bar-logo{font-size:22px}.app-bar-title{font-size:18px;font-weight:700;letter-spacing:.2px}.app-bar-actions{display:flex;gap:4px}.icon-btn{display:inline-flex;align-items:center;justify-content:center;width:38px;height:38px;border:none;border-radius:50%;background:transparent;color:#ffffffd9;cursor:pointer;transition:background .15s ease,color .15s ease}.icon-btn:hover{background:#ffffff2e;color:#fff}.icon-btn.is-active{background:#ffffff40;color:#fff}.contacts{display:flex;flex-direction:column;flex:1;overflow:hidden}.contacts-toolbar{display:flex;align-items:center;gap:8px;padding:12px 14px;border-bottom:1px solid var(--border)}.search-box{flex:1;display:flex;align-items:center;gap:8px;padding:8px 12px;background:var(--bg-hover);border-radius:10px;color:var(--text-soft)}.search-box input{flex:1;border:none;background:transparent;outline:none;font-size:14px;color:var(--text)}.new-chat-btn{display:inline-flex;align-items:center;justify-content:center;width:40px;height:40px;border:none;border-radius:50%;background:var(--brand);color:#fff;cursor:pointer;box-shadow:var(--shadow-sm);transition:background .15s ease,transform .1s ease}.new-chat-btn:hover{background:var(--brand-600)}.new-chat-btn:active{transform:scale(.94)}.new-chat-form{display:flex;gap:8px;padding:12px 14px;border-bottom:1px solid var(--border);background:var(--bg-hover)}.new-chat-form input{flex:1;padding:10px 12px;border:1px solid var(--border);border-radius:10px;outline:none;font-size:14px}.new-chat-form input:focus{border-color:var(--brand)}.new-chat-form button{padding:10px 16px;border:none;border-radius:10px;background:var(--brand);color:#fff;font-weight:600;cursor:pointer}.contact-list{list-style:none;margin:0;padding:0;overflow-y:auto;flex:1}.contact{display:flex;align-items:center;gap:13px;padding:12px 16px;cursor:pointer;border-bottom:1px solid #f3f5f7;transition:background .12s ease}.contact:hover{background:var(--bg-hover)}.contact.selected{background:var(--bg-selected)}.contact-body{flex:1;min-width:0}.contact-row{display:flex;align-items:baseline;justify-content:space-between;gap:8px}.contact-name{font-weight:600;font-size:15px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.contact-time{font-size:12px;color:var(--text-soft);flex-shrink:0}.contact-preview{font-size:13px;color:var(--text-muted);overflow:hidden;text-overflow:ellipsis;white-space:nowrap;margin-top:3px}.empty{padding:24px 16px;color:var(--text-soft);text-align:center;font-size:14px}.avatar{display:inline-flex;align-items:center;justify-content:center;border-radius:50%;color:#fff;font-weight:600;flex-shrink:0;text-transform:uppercase}.sidebar-hint{padding:24px;color:var(--text-muted);line-height:1.6}.main-view{flex:1;display:flex;flex-direction:column;min-width:0}.chat{flex:1;display:flex;flex-direction:column;background-color:var(--bg-chat);background-image:radial-gradient(rgba(15,118,110,.05) 1px,transparent 1px);background-size:22px 22px}.chat--empty{align-items:center;justify-content:center;border-left:4px solid var(--brand)}.chat-placeholder{text-align:center;max-width:420px;padding:32px;color:var(--text-muted)}.chat-placeholder-icon{font-size:56px;margin-bottom:12px}.chat-placeholder h2{margin:0 0 8px;color:var(--text);font-weight:700}.chat-placeholder p{margin:0;line-height:1.6}.chat-header{display:flex;align-items:center;gap:12px;padding:12px 18px;background:var(--bg-panel);border-bottom:1px solid var(--border);box-shadow:var(--shadow-sm);z-index:1}.chat-header-info{min-width:0}.chat-title{font-size:16px;font-weight:700}.chat-status{font-size:12.5px;color:var(--brand-600)}.back-btn{display:none;border:none;background:transparent;color:var(--text-muted);cursor:pointer;padding:4px;border-radius:50%}.back-btn:hover{background:var(--bg-hover)}.chat-messages{flex:1;padding:18px 8%;overflow-y:auto;display:flex;flex-direction:column;gap:6px}.no-messages{margin:auto;color:var(--text-soft);text-align:center;font-size:15px}.day-separator{display:flex;justify-content:center;margin:12px 0}.day-separator span{background:#ffffffeb;color:var(--text-muted);font-size:12px;font-weight:600;padding:5px 12px;border-radius:10px;box-shadow:var(--shadow-sm)}.msg{max-width:62%;padding:7px 10px 6px;border-radius:12px;position:relative;box-shadow:var(--shadow-sm);animation:pop .14s ease}@keyframes pop{0%{transform:translateY(4px);opacity:0}to{transform:none;opacity:1}}.msg.in{background:var(--bubble-in);align-self:flex-start;border-top-left-radius:4px}.msg.out{background:var(--bubble-out);align-self:flex-end;border-top-right-radius:4px}.msg-body{white-space:pre-wrap;word-break:break-word;font-size:14.5px;line-height:1.4}.msg-meta{display:flex;align-items:center;justify-content:flex-end;gap:4px;margin-top:2px}.msg-time{font-size:11px;color:var(--text-soft)}.ticks{color:#53bdeb}.chat-error{margin:0 8% 8px;padding:10px 14px;border-radius:10px;background:#fde8e8;color:#b42318;font-size:13.5px;align-self:center}.chat-input{display:flex;align-items:center;gap:10px;padding:12px 16px;background:var(--bg-panel);border-top:1px solid var(--border)}.chat-input input{flex:1;padding:12px 16px;border:1px solid var(--border);border-radius:22px;outline:none;font-size:14.5px;background:var(--bg-hover);transition:border-color .15s ease,background .15s ease}.chat-input input:focus{border-color:var(--brand);background:#fff}.send-btn{display:inline-flex;align-items:center;justify-content:center;width:46px;height:46px;border:none;border-radius:50%;background:var(--brand);color:#fff;cursor:pointer;flex-shrink:0;transition:background .15s ease,transform .1s ease}.send-btn:hover:not(:disabled){background:var(--brand-600)}.send-btn:active:not(:disabled){transform:scale(.94)}.send-btn:disabled{background:#b9c4c2;cursor:default}.spinner{width:18px;height:18px;border:2.5px solid rgba(255,255,255,.4);border-top-color:#fff;border-radius:50%;animation:spin .7s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.settings-panel{padding:28px;display:flex;flex-direction:column;gap:18px;max-width:640px;width:100%;margin:0 auto;background:var(--bg-panel);height:100%;overflow-y:auto}.settings-title{font-size:24px;font-weight:700}.settings-description{color:var(--text-muted);line-height:1.6}.form-row{display:flex;flex-direction:column;gap:8px}.form-row label{font-size:13px;font-weight:600;color:var(--text-muted);text-transform:uppercase;letter-spacing:.4px}.form-row input{padding:13px 16px;border:1px solid var(--border);border-radius:12px;outline:none;font-size:15px}.form-row input:focus{border-color:var(--brand)}.settings-button{width:fit-content;padding:13px 26px;border:none;border-radius:12px;background:var(--brand);color:#fff;font-weight:700;cursor:pointer;transition:background .15s ease}.settings-button:hover:not(:disabled){background:var(--brand-600)}.settings-button:disabled{opacity:.6;cursor:default}.settings-message{padding:12px 16px;border-radius:12px;background:var(--bg-selected);color:var(--text)}.field-note{font-size:12.5px;color:var(--text-soft)}.login-screen{height:100vh;display:flex;align-items:center;justify-content:center;padding:20px;background:linear-gradient(135deg,var(--brand-700),var(--brand-600))}.login-card{width:100%;max-width:380px;background:var(--bg-panel);border-radius:20px;padding:36px 30px;box-shadow:var(--shadow-md);display:flex;flex-direction:column;gap:14px}.login-logo{font-size:44px;text-align:center}.login-title{margin:0;text-align:center;font-size:24px;font-weight:800}.login-subtitle{margin:0 0 8px;text-align:center;color:var(--text-muted);font-size:14px}.login-error{padding:10px 14px;border-radius:10px;background:#fde8e8;color:#b42318;font-size:13.5px;text-align:center}.login-button{margin-top:6px;padding:14px;border:none;border-radius:12px;background:var(--brand);color:#fff;font-weight:700;font-size:15px;cursor:pointer;transition:background .15s ease}.login-button:hover:not(:disabled){background:var(--brand-600)}.login-button:disabled{opacity:.6;cursor:default}@media (max-width: 768px){.sidebar{width:100%;max-width:none;min-width:0}.main-view{position:fixed;top:0;right:0;bottom:0;left:0;transform:translate(100%);transition:transform .22s ease;background:var(--bg-chat);z-index:5}.app[data-view=detail] .main-view{transform:translate(0)}.back-btn{display:inline-flex}.chat-messages{padding-left:14px;padding-right:14px}.msg{max-width:80%}}@media (prefers-color-scheme: dark){:root{--bg-app: #0b141a;--bg-sidebar: #111b21;--bg-panel: #111b21;--bg-chat: #0b141a;--bg-hover: #202c33;--bg-selected: #2a3942;--bubble-in: #202c33;--bubble-out: #144d3c;--text: #e9edef;--text-muted: #aebac1;--text-soft: #8696a0;--border: #222d34}.day-separator span{background:#182229}.chat-input input:focus{background:#202c33}.chat{background-image:radial-gradient(rgba(255,255,255,.03) 1px,transparent 1px)}.chat-error{background:#3a2020;color:#f6a9a3}}