:root{--bg:#f6f4f0;--surface:#fff;--ink:#262420;--ink-soft:#6b6660;--line:#e3ded4;--accent:#3d6b66;--accent-soft:#e4ece9;--student:#4a5d8a;--student-soft:#eaeef7;--danger:#a14545;--danger-soft:#f6e9e9;--radius:10px;--font:-apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif}*{box-sizing:border-box}body{background:var(--bg);color:var(--ink);font-family:var(--font);margin:0;line-height:1.5}button{cursor:pointer;font-family:inherit}.app-shell{min-height:100vh;display:flex}.app-sidebar{background:var(--surface);border-right:1px solid var(--line);flex-direction:column;flex-shrink:0;gap:20px;width:300px;padding:28px 20px;display:flex}.app-brand h1{letter-spacing:-.01em;margin:0 0 2px;font-size:19px}.app-brand p{color:var(--ink-soft);margin:0;font-size:13px}.sidebar-status{color:var(--ink-soft);font-size:13px}.sidebar-status.is-error{color:var(--danger)}.app-main{flex-direction:column;flex:1;gap:20px;max-width:760px;padding:32px 40px;display:flex}.main-placeholder{color:var(--ink-soft);text-align:center;padding-top:60px}.persona-list{flex-direction:column;gap:8px;display:flex}.persona-card{text-align:left;border:1px solid var(--line);border-radius:var(--radius);background:0 0;flex-direction:column;gap:2px;padding:12px 14px;transition:border-color .15s,background .15s;display:flex}.persona-card:hover:not(:disabled){border-color:var(--accent)}.persona-card.is-selected{border-color:var(--accent);background:var(--accent-soft)}.persona-card:disabled{cursor:not-allowed;opacity:.55}.persona-card-type{font-size:14px;font-weight:600}.persona-card-stage{color:var(--ink-soft);font-size:12px}.persona-empty{color:var(--ink-soft);font-size:13px}.persona-empty-hint code{background:var(--accent-soft);border-radius:4px;padding:1px 4px}.start-button,.reset-button{border-radius:var(--radius);border:none;padding:10px 16px;font-size:14px;font-weight:600}.voice-selector{border:1px solid var(--line);border-radius:var(--radius);color:var(--ink);cursor:pointer;background:#fff;width:100%;margin-bottom:8px;padding:8px 12px;font-family:inherit;font-size:13px}.voice-selector:hover{border-color:var(--accent)}.voice-selector:focus{border-color:var(--accent);outline:none}.start-button{background:var(--accent);color:#fff}.start-button:disabled{opacity:.6;cursor:not-allowed}.reset-button{border:1px solid var(--line);color:var(--ink-soft);background:0 0;margin-top:auto}.reset-button:hover{border-color:var(--danger);color:var(--danger)}.persona-detail{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:18px 22px}.persona-detail-header{cursor:pointer;-webkit-user-select:none;user-select:none;align-items:center;gap:12px;display:flex}.persona-detail-header h2{flex:1;margin:0;font-size:18px}.persona-detail-stage{color:var(--accent);font-size:12px;font-weight:600}.persona-detail-toggle{color:var(--ink-soft);cursor:pointer;background:0 0;border:none;border-radius:4px;padding:4px 8px;font-size:12px;transition:background .15s}.persona-detail-toggle:hover{background:var(--bg)}.persona-detail dl{flex-direction:column;gap:8px;margin:14px 0 0;display:flex}.persona-detail-row{gap:12px;font-size:13px;display:flex}.persona-detail-row dt{color:var(--ink-soft);flex:0 0 84px}.persona-detail-row dd{flex:1;margin:0}.chat-panel{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);flex-direction:column;min-height:420px;margin-top:50px;display:flex;position:relative}.chat-messages{flex-direction:column;flex:1;gap:14px;max-height:480px;padding:18px 20px;display:flex;overflow-y:auto}.chat-empty{color:var(--ink-soft);text-align:center;margin-top:40px;font-size:13px}.message-row{flex-direction:column;gap:3px;max-width:78%;display:flex}.message-row.is-student{align-self:flex-end;align-items:flex-end}.message-row.is-persona{align-self:flex-start;align-items:flex-start}.message-label{color:var(--ink-soft);font-size:11px}.persona-avatar{object-fit:cover;border:2px solid var(--line);border-radius:50%;width:72px;height:72px;transition:transform .15s,border-color .15s}.persona-avatar-fixed{object-fit:cover;border:2px solid var(--line);z-index:10;border-radius:50%;width:100px;height:100px;transition:border-color .15s;position:absolute;top:-50px;left:20px}.persona-avatar-fixed.is-speaking,.persona-avatar.is-speaking{border-color:var(--accent);animation:1s ease-in-out infinite avatar-pulse}@keyframes avatar-pulse{0%,to{transform:scale(1)}50%{transform:scale(1.08)}}.speaking-indicator{animation:1s ease-in-out infinite speaking-pulse;display:inline-block}@keyframes speaking-pulse{0%,to{opacity:1}50%{opacity:.4}}.message-bubble{border-radius:var(--radius);white-space:pre-wrap;padding:9px 13px;font-size:14px}.message-stage-direction{color:var(--ink-soft);opacity:.7;font-style:italic}.is-student .message-bubble{background:var(--student-soft);color:var(--student)}.is-persona .message-bubble{background:var(--accent-soft);color:var(--accent)}.message-bubble-pending{opacity:.6;font-style:italic}.chat-input-row{border-top:1px solid var(--line);flex-direction:column;gap:10px;padding:14px 18px;display:flex}.chat-input-field{display:flex}.chat-input-row textarea{resize:none;border:1px solid var(--line);border-radius:var(--radius);flex:1;padding:10px 12px;font-family:inherit;font-size:14px}.chat-input-row textarea:disabled{background:var(--bg)}.mic-button{border-radius:var(--radius);border:1px solid var(--line);background:var(--surface);-webkit-user-select:none;user-select:none;touch-action:none;align-items:center;gap:6px;padding:8px 16px;font-size:13px;transition:border-color .15s,background .15s,color .15s;display:flex}.mic-button:hover:not(:disabled){border-color:var(--accent)}.mic-button:disabled{opacity:.4;cursor:not-allowed}.mic-button.is-listening{background:var(--danger);border-color:var(--danger);color:#fff;animation:1.4s ease-in-out infinite mic-pulse}.mic-button.is-pending{opacity:.6;cursor:wait}@keyframes mic-pulse{0%,to{box-shadow:0 0 #a1454559}50%{box-shadow:0 0 0 6px #a1454500}}.speech-interim{color:var(--ink-soft);margin:0;font-size:13px;font-style:italic}.speech-error{color:var(--danger);margin:0;font-size:12px}.chat-input-actions{align-items:center;gap:10px;display:flex}.chat-end-button{margin-left:auto}.chat-input-actions button[type=submit]{background:var(--accent);color:#fff;border-radius:var(--radius);border:none;padding:8px 18px;font-size:13px;font-weight:600}.chat-input-actions button[type=submit]:disabled{opacity:.5;cursor:not-allowed}.chat-end-button{border:1px solid var(--line);border-radius:var(--radius);color:var(--ink-soft);background:0 0;padding:8px 14px;font-size:13px}.chat-end-button:disabled{opacity:.5;cursor:not-allowed}.evaluation-panel{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:18px 22px}.evaluation-header{justify-content:space-between;align-items:center;margin-bottom:12px;display:flex}.evaluation-header h3{margin:0;font-size:15px}.export-button{color:var(--accent);border:1px solid var(--accent);border-radius:var(--radius);padding:6px 14px;font-size:13px;text-decoration:none}.export-button:hover{background:var(--accent-soft)}.evaluation-text{white-space:pre-wrap;color:var(--ink);margin:0;font-family:inherit;font-size:13px;line-height:1.7}.evaluation-session-id{color:var(--ink-soft);margin:14px 0 0;font-size:11px}.error-banner{background:var(--danger-soft);color:var(--danger);border-radius:var(--radius);padding:10px 14px;font-size:13px}@media (width<=720px){.app-shell{flex-direction:column}.app-sidebar{border-right:none;border-bottom:1px solid var(--line);width:auto}.app-sidebar.has-session .persona-list{display:none}.app-main{max-width:none;padding:20px}}