:root{--bg-base: #0f0f17;--bg-surface: #161622;--bg-card: #1e1e2e;--bg-elevated: #252535;--bg-input: #1a1a28;--border: #313244;--border-focus: #6c7fff;--text-primary: #cdd6f4;--text-secondary: #a6adc8;--text-muted: #6c7086;--accent: #6c7fff;--accent-hover: #8b9fff;--accent-glow: rgba(108, 127, 255, .25);--success: #a6e3a1;--danger: #f38ba8;--warning: #f9e2af;--info: #89dceb;--font-sans: "Inter", system-ui, sans-serif;--font-mono: "JetBrains Mono", "Fira Code", monospace;--radius-sm: 6px;--radius-md: 10px;--radius-lg: 16px;--radius-full: 9999px;--transition: .18s ease;--shadow-sm: 0 1px 4px rgba(0, 0, 0, .4);--shadow-md: 0 4px 16px rgba(0, 0, 0, .5);--shadow-lg: 0 8px 32px rgba(0, 0, 0, .6);--glow: 0 0 24px var(--accent-glow)}*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}html{font-size:16px;scroll-behavior:smooth}body{font-family:var(--font-sans);background:var(--bg-base);color:var(--text-primary);min-height:100vh;line-height:1.6;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}button{cursor:pointer;font-family:inherit}input,textarea{font-family:inherit}::-webkit-scrollbar{width:6px;height:6px}::-webkit-scrollbar-track{background:var(--bg-base)}::-webkit-scrollbar-thumb{background:var(--border);border-radius:var(--radius-full)}::-webkit-scrollbar-thumb:hover{background:var(--text-muted)}h1{font-size:clamp(2rem,5vw,3rem);font-weight:800;letter-spacing:-.03em}h2{font-size:1.5rem;font-weight:700}h3{font-size:1.1rem;font-weight:600}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:10px 20px;border:none;border-radius:var(--radius-md);font-size:.9rem;font-weight:600;letter-spacing:.02em;transition:all var(--transition);outline:none;position:relative;overflow:hidden}.btn:focus-visible{outline:2px solid var(--accent);outline-offset:2px}.btn:disabled{opacity:.45;cursor:not-allowed}.btn-primary{background:var(--accent);color:#fff}.btn-primary:hover:not(:disabled){background:var(--accent-hover);transform:translateY(-1px);box-shadow:var(--glow)}.btn-outline{background:transparent;border:1.5px solid var(--border);color:var(--text-secondary)}.btn-outline:hover:not(:disabled){border-color:var(--accent);color:var(--text-primary);background:var(--accent-glow)}.btn-ghost{background:transparent;color:var(--text-muted)}.btn-ghost:hover:not(:disabled){color:var(--text-primary);background:var(--bg-elevated)}.btn-danger{background:transparent;border:1.5px solid var(--danger);color:var(--danger)}.btn-danger:hover:not(:disabled){background:#f38ba81a}.btn-sm{padding:6px 12px;font-size:.8rem;border-radius:var(--radius-sm)}.btn-lg{padding:14px 28px;font-size:1rem;border-radius:var(--radius-lg)}.btn-full{width:100%}.btn-icon{padding:8px;border-radius:var(--radius-sm)}.form-group{display:flex;flex-direction:column;gap:6px}.form-label{font-size:.82rem;font-weight:500;color:var(--text-secondary);letter-spacing:.05em;text-transform:uppercase}.form-input{width:100%;padding:10px 14px;background:var(--bg-input);border:1.5px solid var(--border);border-radius:var(--radius-md);color:var(--text-primary);font-size:.95rem;transition:border-color var(--transition),box-shadow var(--transition);outline:none}.form-input:focus{border-color:var(--border-focus);box-shadow:0 0 0 3px var(--accent-glow)}.form-input::placeholder{color:var(--text-muted)}.form-input.code-input{font-family:var(--font-mono);font-size:1.2rem;letter-spacing:.2em;text-align:center;text-transform:uppercase}.card{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);padding:24px}.card-sm{padding:16px;border-radius:var(--radius-md)}.divider{display:flex;align-items:center;gap:12px;color:var(--text-muted);font-size:.82rem;margin:8px 0}.divider:before,.divider:after{content:"";flex:1;height:1px;background:var(--border)}.badge{display:inline-flex;align-items:center;gap:5px;padding:3px 10px;border-radius:var(--radius-full);font-size:.75rem;font-weight:600;background:var(--bg-elevated);border:1px solid var(--border);color:var(--text-secondary)}.badge-accent{background:var(--accent-glow);border-color:var(--accent);color:var(--accent)}.badge-success{background:#a6e3a11f;border-color:var(--success);color:var(--success)}.badge-danger{background:#f38ba81f;border-color:var(--danger);color:var(--danger)}.spinner{width:18px;height:18px;border:2px solid rgba(255,255,255,.15);border-top-color:var(--accent);border-radius:50%;animation:spin .7s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.pulse-dot{width:8px;height:8px;border-radius:50%;background:var(--success);position:relative}.pulse-dot:after{content:"";position:absolute;inset:-3px;border-radius:50%;background:var(--success);opacity:.4;animation:pulse 2s ease-in-out infinite}@keyframes pulse{0%,to{transform:scale(1);opacity:.4}50%{transform:scale(1.6);opacity:0}}@keyframes fadeInUp{0%{opacity:0;transform:translateY(16px)}to{opacity:1;transform:translateY(0)}}.fade-in{animation:fadeInUp .4s ease both}.home-page{min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:24px;position:relative;overflow:hidden}.home-bg-glow{position:absolute;width:600px;height:600px;border-radius:50%;background:radial-gradient(circle,rgba(108,127,255,.08) 0%,transparent 70%);top:-200px;left:50%;transform:translate(-50%);pointer-events:none}.home-container{width:100%;max-width:460px}.home-logo{text-align:center;margin-bottom:48px}.home-logo .logo-icon{font-size:3rem;margin-bottom:12px;display:block}.home-logo h1{background:linear-gradient(135deg,var(--accent) 0%,#b8bfff 100%);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.home-logo p{color:var(--text-muted);margin-top:8px;font-size:.95rem}.home-cards{display:flex;flex-direction:column;gap:16px}.home-card{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-lg);padding:28px;transition:border-color var(--transition),box-shadow var(--transition)}.home-card:hover{border-color:#6c7fff66;box-shadow:var(--shadow-md)}.home-card-header{display:flex;align-items:center;gap:10px;margin-bottom:18px}.home-card-icon{font-size:1.3rem}.home-card-title{font-size:1rem;font-weight:600;color:var(--text-primary)}.home-card-sub{font-size:.82rem;color:var(--text-muted);margin-top:2px}.home-footer{text-align:center;margin-top:32px;font-size:.78rem;color:var(--text-muted)}.room-page{min-height:100vh;display:flex;flex-direction:column}.room-header{background:var(--bg-card);border-bottom:1px solid var(--border);padding:14px 24px;display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;position:sticky;top:0;z-index:50;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px)}.room-header-left{display:flex;align-items:center;gap:16px;flex-wrap:wrap}.room-header-right{display:flex;align-items:center;gap:12px}.room-code-display{display:flex;align-items:center;gap:8px}.room-code-label{font-size:.72rem;color:var(--text-muted);text-transform:uppercase;letter-spacing:.08em}.room-code-value{font-family:var(--font-mono);font-size:1.05rem;font-weight:700;color:var(--accent);letter-spacing:.18em}.user-count{display:flex;align-items:center;gap:7px;font-size:.85rem;color:var(--text-secondary)}.user-count-num{font-weight:700;color:var(--success)}.room-timer{display:flex;align-items:center;gap:7px;font-size:.82rem;font-family:var(--font-mono);color:var(--text-muted)}.room-timer.urgent{color:var(--danger)}.room-body{flex:1;display:grid;grid-template-columns:1fr 380px;grid-template-rows:1fr auto;gap:0;overflow:hidden;height:calc(100vh - 65px)}.room-main{display:flex;flex-direction:column;overflow:hidden}.room-sidebar{display:flex;flex-direction:column;border-left:1px solid var(--border);overflow:hidden;background:var(--bg-surface)}@media(max-width:768px){.room-body{grid-template-columns:1fr;grid-template-rows:auto 1fr auto;height:auto;min-height:calc(100vh - 65px)}.room-sidebar{border-left:none;border-top:1px solid var(--border)}}.tab-bar{display:flex;border-bottom:1px solid var(--border);background:var(--bg-surface);padding:0 4px}.tab-btn{padding:12px 18px;font-size:.85rem;font-weight:500;color:var(--text-muted);background:transparent;border:none;border-bottom:2px solid transparent;cursor:pointer;transition:all var(--transition);display:flex;align-items:center;gap:7px}.tab-btn:hover{color:var(--text-primary)}.tab-btn.active{color:var(--accent);border-bottom-color:var(--accent)}.chat-section{display:flex;flex-direction:column;height:100%;overflow:hidden}.messages-container{flex:1;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:10px}.messages-empty{flex:1;display:flex;flex-direction:column;align-items:center;justify-content:center;color:var(--text-muted);gap:10px;font-size:.9rem}.messages-empty-icon{font-size:2.5rem;opacity:.5}.message-bubble{display:flex;gap:10px;animation:fadeInUp .25s ease both;max-width:85%}.message-bubble.own{flex-direction:row-reverse;align-self:flex-end}.message-bubble.other{align-self:flex-start}.msg-avatar{width:32px;height:32px;border-radius:var(--radius-full);background:var(--bg-elevated);border:1px solid var(--border);display:flex;align-items:center;justify-content:center;font-size:.8rem;font-weight:700;color:var(--accent);flex-shrink:0;margin-top:2px}.msg-body{display:flex;flex-direction:column;gap:3px}.msg-meta{display:flex;align-items:baseline;gap:8px;font-size:.72rem;color:var(--text-muted)}.message-bubble.own .msg-meta{flex-direction:row-reverse}.msg-sender{font-weight:600;color:var(--text-secondary)}.msg-content{padding:10px 14px;border-radius:var(--radius-md);font-size:.9rem;line-height:1.5;word-break:break-word}.msg-content.text{background:var(--bg-elevated);border:1px solid var(--border);color:var(--text-primary)}.message-bubble.own .msg-content.text{background:var(--accent);color:#fff;border-color:transparent}.msg-content.file{background:var(--bg-elevated);border:1px solid var(--border-focus);color:var(--text-primary);display:flex;flex-direction:column;gap:8px}.file-link{display:flex;align-items:center;gap:8px;color:var(--accent);font-size:.85rem;font-weight:500;text-decoration:none}.file-link:hover{text-decoration:underline}.file-link-icon{font-size:1.2rem}.chat-input-area{padding:12px 16px;border-top:1px solid var(--border);background:var(--bg-surface)}.chat-input-row{display:flex;gap:8px;align-items:flex-end}.chat-textarea{flex:1;padding:10px 14px;background:var(--bg-input);border:1.5px solid var(--border);border-radius:var(--radius-md);color:var(--text-primary);font-size:.9rem;resize:none;min-height:42px;max-height:120px;transition:border-color var(--transition);outline:none;line-height:1.5}.chat-textarea:focus{border-color:var(--border-focus)}.chat-textarea::placeholder{color:var(--text-muted)}.code-section{display:flex;flex-direction:column;height:100%;overflow:hidden;background:var(--bg-base)}.code-toolbar{display:flex;align-items:center;justify-content:space-between;padding:10px 16px;border-bottom:1px solid var(--border);background:var(--bg-surface);gap:12px;flex-wrap:wrap}.lang-select{padding:6px 10px;background:var(--bg-input);border:1px solid var(--border);border-radius:var(--radius-sm);color:var(--text-primary);font-size:.82rem;outline:none;cursor:pointer}.lang-select:focus{border-color:var(--border-focus)}.code-editor-wrapper{flex:1;overflow:hidden}.file-section{display:flex;flex-direction:column;height:100%;overflow:hidden;padding:20px;gap:16px}.dropzone{flex:1;border:2px dashed var(--border);border-radius:var(--radius-lg);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:12px;cursor:pointer;transition:all var(--transition);padding:40px 20px;text-align:center}.dropzone:hover,.dropzone.drag-over{border-color:var(--accent);background:var(--accent-glow)}.dropzone-icon{font-size:2.5rem;opacity:.6}.dropzone-title{font-weight:600;color:var(--text-secondary)}.dropzone-hint{font-size:.8rem;color:var(--text-muted)}.file-queue{display:flex;flex-direction:column;gap:8px}.file-item{display:flex;align-items:center;justify-content:space-between;padding:10px 14px;background:var(--bg-elevated);border:1px solid var(--border);border-radius:var(--radius-md);font-size:.85rem}.file-item-name{font-weight:500;truncate:ellipsis;flex:1;min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.file-item-size{color:var(--text-muted);font-size:.78rem;flex-shrink:0;margin:0 12px}.file-upload-actions{display:flex;gap:8px;margin-top:4px}.room-error-page{min-height:100vh;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:20px;padding:24px;text-align:center}.room-error-icon{font-size:4rem;opacity:.6}.room-error-title{font-size:1.5rem;font-weight:700;color:var(--danger)}.room-error-msg{color:var(--text-muted);max-width:360px}