:root{--blue:#2087f4;--blue-dark:#1673d7;--text:#202d40;--muted:#88929f;--line:#e9edf2;--panel:#f7f8fa;--mint:#7bbbaf;--shadow:0 8px 32px #1e3b6510;font-family:"Microsoft YaHei","PingFang SC",system-ui,sans-serif;color:var(--text);font-size:14px}*{box-sizing:border-box}body{margin:0;background:white}button,input,textarea,select{font:inherit}button{cursor:pointer;transition:background .16s,color .16s,transform .16s}button:disabled{cursor:not-allowed;opacity:.5}button:focus-visible,a:focus-visible,summary:focus-visible{outline:3px solid #98cfff;outline-offset:3px}button:active:not(:disabled){transform:translateY(1px)}button svg{width:21px;height:21px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}textarea,select{outline:none;color:var(--text)}textarea:focus,select:focus{border-color:#9bcafa!important;box-shadow:0 0 0 3px #2087f410}textarea{resize:none}button{border:0;background:transparent;color:inherit}[hidden]{display:none!important}.app-shell{height:100dvh;display:grid;grid-template-columns:238px minmax(0,1fr) 288px;max-width:1900px;margin:auto;overflow:hidden}.sidebar{background:#f7f8fb;border-right:1px solid var(--line);padding:29px 20px 17px;display:flex;flex-direction:column;min-height:0}.brand{display:flex;align-items:center;gap:11px;color:var(--text);text-decoration:none;font-weight:650;font-size:17px;letter-spacing:-.3px;white-space:nowrap}.brand small{display:block;color:#8792a3;font-weight:400;font-size:11px;letter-spacing:2px;margin-top:5px}.brand-mark{display:grid;place-items:center;background:linear-gradient(145deg,#59b4ff,#1979e9);color:white;width:38px;height:42px;border-radius:13px 13px 13px 4px;font-family:"KaiTi",serif;font-size:24px;box-shadow:0 4px 9px #2087f424}.new-session{margin-top:35px;display:flex;align-items:center;justify-content:center;gap:10px;background:#eaf3ff;color:#247bdc;border:1px solid #daeafd;border-radius:10px;font-weight:550;padding:12px}.new-session:hover{background:#e0edff}.new-session span{font-size:20px;line-height:1}.sidebar-label{display:flex;justify-content:space-between;margin:30px 9px 12px;color:#8a94a4;font-size:12px}.sidebar-label span{background:#e9edf2;min-width:18px;text-align:center;border-radius:5px;color:#8993a0}.history-list{overflow:auto;flex:1;min-height:0}.history-item{width:100%;text-align:left;padding:12px 11px;border-radius:9px;margin-bottom:4px;color:#586477;font-size:13px;display:block}.history-item:hover{background:#edf0f5}.history-item.active{background:white;box-shadow:0 2px 8px #243b5510;color:#247bdc}.history-item strong{display:block;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;font-size:13px;font-weight:500;line-height:1.6}.history-item small{display:block;color:#95a0af;font-size:10px;margin-top:5px}.empty-history{padding:17px 10px;line-height:1.9;color:#a2aab7;font-size:12px}.sidebar-bottom{padding:18px 4px 0;border-top:1px solid #e6eaf0;color:#919baa;font-size:10px;line-height:1.8}.sidebar-bottom small{display:block;font-size:10px;color:#a5adba;margin-left:12px}.device-dot{display:inline-block;width:5px;height:5px;border-radius:50%;background:#a2b6c8;vertical-align:2px;margin-right:6px}.main-panel{min-width:0;display:flex;flex-direction:column;position:relative}.topbar{height:89px;flex-shrink:0;border-bottom:1px solid var(--line);display:flex;align-items:center;padding:0 34px;gap:15px}.page-title{min-width:0;flex:1}.page-title strong{display:block;font-size:16px;font-weight:550;white-space:nowrap;text-overflow:ellipsis;overflow:hidden;line-height:1.6}.page-title small{display:block;color:#9aA3b1;font-size:11px;letter-spacing:.7px;margin-top:3px}.topbar-actions{display:flex;align-items:center;gap:6px}.mode-badge{white-space:nowrap;background:#f0f4f8;color:#708196;border:1px solid #e5ecf4;border-radius:6px;padding:5px 8px;font-size:10px;margin-right:7px}.mode-badge.model{color:#3a8c75;background:#eef8f3;border-color:#deeee6}.icon-button{height:34px;width:34px;border-radius:8px;display:grid;place-items:center;color:#8c96a3}.icon-button:hover{background:#f1f4f8;color:#4a607a}.mobile-menu,.settings-toggle,.close-settings{display:none}.stage-nav{display:flex;align-items:center;justify-content:center;gap:12px;height:68px;flex-shrink:0;padding:0 22px;border-bottom:1px solid #f0f2f6}.stage-nav button{font-size:12px;color:#909aa8;display:flex;align-items:center;gap:7px;white-space:nowrap;padding:7px 2px}.stage-nav button span{height:22px;width:22px;border-radius:50%;border:1px solid #dce3eb;display:grid;place-items:center;font-size:10px;background:#fff}.stage-nav button.current{color:#287eda;font-weight:550}.stage-nav button.current span{color:white;border-color:var(--blue);background:var(--blue);box-shadow:0 2px 5px #2087f42b}.stage-nav button.done{color:#657e98}.stage-nav button.done span{background:#eff5fc;border-color:#d6e7f9;color:#3988dc}.stage-nav i{height:1px;width:23px;background:#e7edf5}.chat-scroll{flex:1;min-height:0;overflow:auto;scroll-behavior:smooth;padding:29px 34px 32px;scrollbar-width:thin;scrollbar-color:#dce3eb transparent}.welcome{text-align:center;max-width:630px;margin:clamp(35px,7vh,95px) auto 25px}.welcome-symbol{color:var(--blue);font-size:43px;margin-bottom:21px;line-height:1}.eyebrow{font-size:10px;letter-spacing:1.5px;color:#96a3b5;margin:0}.welcome .eyebrow{font-size:11px;letter-spacing:2px}.welcome h1{font-size:clamp(26px,2.2vw,34px);font-weight:600;letter-spacing:1px;margin:14px 0 15px;color:#273a51}.welcome-description{font-size:14px;line-height:1.95;color:#8b95a4;margin:0}.welcome-features{margin:25px 0 29px;display:flex;justify-content:center;gap:23px;font-size:11px;color:#8493a5}.primary-button{background:var(--blue);color:white;border-radius:9px;padding:13px 21px;font-weight:500;box-shadow:0 5px 14px #2087f422}.primary-button:hover{background:var(--blue-dark)}.start-button{display:inline-flex;gap:34px;align-items:center;font-size:13px}.start-button span{font-size:20px;line-height:1}.welcome-note{font-size:10px;color:#a0a9b6;margin-top:14px}.conversation{max-width:860px;margin:auto}.question-card{border:1px solid #e6edf5;border-radius:13px;background:#fbfcff;overflow:hidden}.question-card summary{list-style:none;cursor:pointer;display:flex;align-items:center;gap:10px;padding:16px 18px;font-weight:550}.question-card summary::-webkit-details-marker{display:none}.question-label{font-size:10px;color:#3782d3;background:#eaf3ff;padding:4px 6px;border-radius:4px;flex-shrink:0}.question-card summary>span:nth-child(2){flex:1;line-height:1.6;font-size:13px}.question-card summary svg{width:18px;height:18px;stroke:#879eb6;stroke-width:1.5;fill:none;flex-shrink:0}.question-card:not([open]) summary svg{transform:rotate(-90deg)}.question-content{padding:0 20px 18px}.question-tags{display:flex;gap:7px;flex-wrap:wrap;margin-bottom:13px}.question-tags span{padding:3px 7px;background:#f0f3f8;border-radius:4px;font-size:10px;color:#8797aa}.question-content>p{font-size:13px;line-height:1.9;margin:0 0 14px;white-space:pre-wrap;color:#5d6c80}.question-requirements{border-top:1px dashed #dde7f2;padding-top:12px}.question-requirements strong{font-size:11px;color:#748399;font-weight:550}.question-requirements p{font-size:12px;color:#6f7e92;line-height:1.8;margin:5px 0 0;white-space:pre-wrap}.question-content p.source-note{color:#a0acba;font-size:10px;line-height:1.6;margin:12px 0 0}.training-tip{display:flex;gap:9px;align-items:center;color:#7995b4;margin:18px 0 20px;padding:0 3px;font-size:11px;line-height:1.8}.training-tip>span{font-size:18px;color:#7aa8dc}.training-tip p{flex:1;margin:0}.training-tip button{color:#548bc8;white-space:nowrap;padding:6px}.messages{display:flex;flex-direction:column;gap:23px;padding-top:4px}.message{display:flex;align-items:flex-start;gap:10px;max-width:100%}.message.user{justify-content:flex-end}.avatar{width:27px;height:29px;border-radius:9px;background:#edf5ff;color:#5199e5;display:grid;place-items:center;font-size:15px;flex-shrink:0;margin-top:3px}.message-body{max-width:calc(100% - 37px);min-width:0}.bubble{font-size:13px;line-height:1.95;white-space:pre-wrap;overflow-wrap:anywhere;background:#f4f6f9;border-radius:3px 13px 13px 13px;padding:16px 20px;color:#425064}.message.user .message-body{max-width:85%}.message.user .bubble{background:linear-gradient(115deg,#339bf9,#2189f3);border-radius:13px 3px 13px 13px;color:white;padding:13px 19px;box-shadow:0 3px 9px #248bf414}.message-meta{font-size:9px;color:#a5afbd;padding:6px 2px 0}.message.user .message-meta{text-align:right}.checks{padding:12px 15px;border:1px solid #e5edf6;border-radius:9px;margin-top:10px;background:#fafdff}.checks-label{font-size:10px;letter-spacing:.4px;color:#7790aa;margin-bottom:7px}.check-item{font-size:11px;color:#687d94;line-height:1.7;white-space:pre-wrap;margin-top:4px}.pending .bubble{display:flex;align-items:center;gap:6px;padding:19px 22px;white-space:normal}.pending .bubble b{width:5px;height:5px;background:#9eb5d0;border-radius:50%;animation:breath 1.25s infinite}.pending .bubble b:nth-child(2){animation-delay:.15s}.pending .bubble b:nth-child(3){animation-delay:.3s}.pending .bubble span{color:#9aa9bc;font-size:11px;margin-left:7px}@keyframes breath{50%{opacity:.25;transform:translateY(-3px)}}.composer-area{flex-shrink:0;padding:0 34px 14px;background:white}.composer{border:1px solid #e4eaf1;border-radius:16px;padding:15px 17px 12px;box-shadow:var(--shadow);max-width:860px;margin:auto;transition:border-color .2s}.composer:focus-within{border-color:#a5ccf6}.composer.listening{border-color:#6cafed;box-shadow:0 0 0 3px #2087f410}.composer textarea{display:block;width:100%;border:0;background:transparent;min-height:43px;max-height:150px;line-height:1.75;font-size:13px;padding:0 2px;box-shadow:none}.composer textarea::placeholder{color:#b0b7c3}.composer textarea:focus{box-shadow:none}.composer-bottom{display:flex;align-items:center;justify-content:space-between;margin-top:10px;gap:10px}.input-tools,.send-tools{display:flex;align-items:center;gap:13px;min-width:0}.voice-button{display:flex;align-items:center;gap:5px;color:#8b9aab;font-size:10px;white-space:nowrap;padding:5px 0}.voice-button:hover{color:var(--blue)}.voice-button svg{width:16px;height:17px;stroke-width:1.5}.voice-button.recording{color:#e37373}.input-hint{font-size:9px;color:#b1b8c3;line-height:1.5}.send-button{background:#e9f2fd;color:#408de0;width:33px;height:33px;border-radius:10px;display:grid;place-items:center;flex-shrink:0}.send-button:not(:disabled){background:var(--blue);color:white}.send-button svg{height:19px;width:19px}.send-button:not(:disabled):hover{background:var(--blue-dark)}.stop-button{font-size:11px;color:#7c8a9c;background:#f1f4f8;border-radius:7px;padding:8px 10px}.composer-disclaimer{margin:10px auto 0;font-size:9px;color:#a5aebc;text-align:center;line-height:1.7;max-width:860px}.inline-notice{max-width:860px;margin:0 auto 11px;padding:9px 13px;border:1px solid #eadfc4;background:#fffbf1;color:#9c8250;border-radius:8px;font-size:11px;line-height:1.7}.inline-notice.error{border-color:#f1d7d7;background:#fff7f7;color:#b45f5f}.settings-panel{border-left:1px solid var(--line);background:#fcfcfe;padding:30px 23px 20px;overflow:auto;scrollbar-width:thin;scrollbar-color:#e3e8ef transparent}.settings-heading{display:flex;align-items:center;justify-content:space-between;margin-bottom:27px}.settings-heading h2{font-size:18px;font-weight:550;margin:7px 0 0;letter-spacing:.5px}.settings-heading .eyebrow{font-size:8px;letter-spacing:2px}.settings-section{padding-bottom:23px;margin-bottom:22px;border-bottom:1px solid var(--line)}.settings-section h3{font-size:12px;font-weight:500;margin:0 0 17px;display:flex;gap:8px;align-items:center}.section-dot{width:6px;height:6px;display:inline-block;border-radius:50%}.blue{background:#69a8ec}.mint{background:#88bdb0}.settings-section label{display:block;font-size:10px;color:#8a96a6;margin:14px 0 7px}.settings-section select{width:100%;border:1px solid #e4eaf2;border-radius:7px;background:white;padding:10px 9px;font-size:11px;appearance:auto}.settings-section textarea{width:100%;border:1px solid #e4eaf2;border-radius:7px;background:white;padding:10px 11px;font-size:11px;line-height:1.7}.settings-section textarea::placeholder{color:#abb5c4}.outline-button{width:100%;border:1px solid #d7e7fb;color:#4487d0;border-radius:7px;margin-top:17px;padding:9px;font-size:11px;background:#f8fbff;display:flex;align-items:center;justify-content:center;gap:40px}.outline-button:hover{background:#edf5ff}.outline-button span{font-size:16px}.field-note{font-size:9px;color:#a5aeba;line-height:1.9;margin:9px 0 0}.save-preferences{margin-top:10px;width:100%;background:#f0f3f7;color:#687c94;border-radius:7px;padding:10px;font-size:11px}.save-preferences:hover{background:#e8eef5}.settings-note{display:flex;gap:9px;padding:0 2px;color:#99a7b6;line-height:1.9;font-size:10px}.settings-note span{font-size:20px;color:#b4c3d2}.settings-note p{margin:0}.toast{position:fixed;bottom:35px;left:50%;transform:translateX(-50%);background:#273a50eF;color:white;padding:12px 20px;border-radius:10px;box-shadow:0 8px 25px #172a402a;font-size:12px;z-index:50;max-width:min(90vw,540px);line-height:1.7}.sr-only{position:absolute;height:1px;width:1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap}.drawer-overlay{position:fixed;inset:0;background:#19334c44;z-index:20;backdrop-filter:blur(2px)}
@media(min-width:1600px){.app-shell{grid-template-columns:260px minmax(0,1fr) 320px}.sidebar{padding-left:26px;padding-right:26px}.settings-panel{padding-left:28px;padding-right:28px}.chat-scroll{padding-left:54px;padding-right:54px}.topbar{padding-left:54px;padding-right:54px}.composer-area{padding-left:54px;padding-right:54px}.welcome{margin-top:11vh}}
@media(max-width:1200px){.app-shell{grid-template-columns:215px minmax(0,1fr) 260px}.sidebar{padding-left:16px;padding-right:16px}.brand{font-size:15px}.brand-mark{width:33px;height:37px;font-size:21px}.settings-panel{padding-left:18px;padding-right:18px}.topbar{padding-left:24px;padding-right:24px}.chat-scroll{padding-left:24px;padding-right:24px}.composer-area{padding-left:24px;padding-right:24px}.stage-nav{gap:7px}.stage-nav i{width:12px}.stage-nav button{font-size:11px;gap:5px}.input-hint{display:none}}
@media(max-width:1030px){.app-shell{grid-template-columns:215px minmax(0,1fr)}.settings-panel{position:fixed;right:0;top:0;bottom:0;width:300px;z-index:30;transform:translateX(100%);transition:transform .2s;box-shadow:-5px 0 30px #263e6512}.settings-panel.open{transform:translateX(0)}.settings-toggle,.close-settings{display:grid}.welcome{margin-top:8vh}.input-hint{display:inline}.stage-nav{gap:12px}.stage-nav i{width:20px}}
@media(max-width:700px){.app-shell{display:flex}.main-panel{width:100%;height:100dvh}.sidebar{position:fixed;top:0;bottom:0;left:0;width:265px;z-index:30;transform:translateX(-100%);transition:transform .2s;padding:27px 23px 20px}.sidebar.open{transform:translateX(0)}.mobile-menu{display:grid;flex-shrink:0}.topbar{height:73px;padding:0 14px;gap:8px}.page-title strong{font-size:14px}.page-title small{font-size:9px;margin-top:1px;letter-spacing:0}.topbar-actions{gap:2px}.icon-button{width:29px;height:32px}.icon-button svg{width:18px;height:18px}.mode-badge{font-size:8px;padding:4px 5px;margin-right:2px}.stage-nav{height:58px;gap:7px;padding:0 12px;justify-content:space-between}.stage-nav button{font-size:10px;gap:4px}.stage-nav button span{height:18px;width:18px;font-size:8px}.stage-nav i{width:8px}.chat-scroll{padding:21px 17px 27px}.welcome{margin-top:8vh}.welcome h1{font-size:27px;margin-top:13px}.welcome-description{font-size:12px;line-height:2}.welcome .eyebrow{font-size:9px;letter-spacing:1.4px}.welcome-features{font-size:10px;gap:17px;margin-top:23px;margin-bottom:26px}.welcome-symbol{font-size:37px}.composer-area{padding:0 13px 10px}.composer{border-radius:14px;padding:13px 14px 10px}.composer textarea{font-size:13px}.composer-disclaimer{font-size:8px;padding:0 4px}.input-hint{display:none}.bubble{font-size:13px;padding:14px 16px;line-height:1.85}.avatar{width:23px;height:26px;font-size:14px}.message{gap:8px}.message-body{max-width:calc(100% - 31px)}.message.user .message-body{max-width:88%}.question-card summary{padding:14px;gap:8px}.question-content{padding:0 16px 16px}.question-card summary>span:nth-child(2){font-size:12px}.question-label{font-size:8px}.question-content>p{font-size:12px;line-height:1.95}.training-tip{font-size:10px;gap:7px;margin:16px 0 19px}.training-tip button{font-size:10px}.settings-panel{width:min(310px,90vw)}.toast{bottom:150px}}
@media(max-width:390px){.topbar{padding:0 9px}.mode-badge{display:none}.stage-nav{gap:3px}.stage-nav i{width:5px}.stage-nav button{font-size:9px;gap:3px}.page-title strong{font-size:13px}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important;animation:none!important}}
.question-card-heading{display:flex;align-items:center;gap:10px;padding:16px 20px}.question-card-heading strong{font-size:13px;font-weight:550;line-height:1.6}.question-content p.question-paper-heading{font-weight:550;color:#445870;margin-bottom:16px}.question-content p.question-task-prompt{color:#4b6079;margin-top:14px}.question-hints{margin-top:15px;border-top:1px dashed #e1e8f1;padding-top:12px}.question-hints summary{list-style:none;display:flex;align-items:center;justify-content:space-between;padding:0;color:#7192b9;font-size:11px;font-weight:400;cursor:pointer}.question-hints summary::-webkit-details-marker{display:none}.question-hints summary span{font-size:17px;line-height:1}.question-hints[open] summary span{transform:rotate(180deg)}.question-hints-content{padding:5px 0 0}.question-hints-content p{font-size:10px;color:#8394a9;line-height:1.9;white-space:pre-wrap;margin:9px 0}.question-hints-content a{color:#4e89ce;text-decoration:none;border-bottom:1px solid #cbdcef;overflow-wrap:anywhere}.question-hints-content .question-tags{margin:10px 0}.oral-task{margin-top:18px;padding:19px 20px 17px;background:#fff;border:1px solid #e6edf4;border-radius:12px}.oral-task-heading{display:flex;align-items:center;gap:11px;flex-wrap:wrap}.oral-task-heading h2{margin:0;font-size:13px;font-weight:550;color:#49607b}.oral-task-heading>span{font-size:9px;color:#6e9b8f;background:#eff7f3;border-radius:4px;padding:3px 6px}.oral-task-intro{font-size:11px;line-height:1.85;color:#8996a7;margin:10px 0 15px}.reading-timer{display:flex;align-items:center;justify-content:space-between;background:#f7f9fc;border-radius:8px;padding:11px 13px;gap:10px}.reading-timer>div{display:flex;align-items:center;gap:13px}.timer-label{font-size:10px;color:#8a9cb2}.reading-timer strong{font-family:Consolas,"SFMono-Regular",monospace;font-size:21px;color:#5a84b7;font-weight:500;font-variant-numeric:tabular-nums;letter-spacing:1px}.timer-actions button{font-size:10px;padding:6px 10px;border-radius:5px;color:#6f8db0;background:white;border:1px solid #e2eaf4}.timer-actions button:first-child{color:#387fcb;border-color:#dbe9f9}.timer-actions button:hover{background:#eef5ff}.reading-timer .timer-actions{gap:7px}.timer-status{font-size:9px;color:#a0acba;line-height:1.7;margin:7px 0 13px}.oral-task-list{margin:0;padding-left:20px;display:grid;grid-template-columns:1fr 1fr;gap:8px 24px;font-size:11px;line-height:1.75;color:#71859f}.oral-task-list li::marker{color:#9ab2ce;font-size:10px}.oral-task-scaffold{font-size:10px;line-height:1.9;color:#91a0b2;padding:11px 12px;margin:15px 0 0;background:#fafbfd;border-radius:6px}.oral-task-scaffold strong{font-weight:500;color:#8093ab}.oral-task-note{font-size:9px;color:#a0abba;line-height:1.8;margin:9px 0 0}.question-content p.source-note{margin-top:9px;margin-bottom:0}
@media(max-width:700px){.question-card-heading{padding:14px 16px}.question-card-heading strong{font-size:12px}.question-content p.question-paper-heading{font-size:12px;line-height:1.9}.oral-task{padding:16px;margin-top:16px}.oral-task-list{grid-template-columns:1fr;gap:7px;font-size:11px}.oral-task-heading h2{font-size:12px}.oral-task-intro{font-size:10px}.reading-timer{padding:10px;gap:5px}.reading-timer>div{gap:8px}.reading-timer strong{font-size:20px}.timer-label{font-size:9px}.timer-actions button{padding:6px 8px;font-size:9px}.reading-timer .timer-actions{gap:5px}}
/* Grid children must shrink so the conversation, rather than the whole shell, scrolls. */
html,body{height:100%;overflow:hidden}.main-panel{min-height:0;overflow:hidden}.settings-panel{min-height:0}
@media(max-width:390px){.mode-badge{display:inline-block;font-size:8px;padding:3px 4px}.topbar-actions{gap:0}.page-title strong{font-size:12px}}

.practice-mode{display:flex;align-items:center;gap:12px;flex-wrap:wrap;margin:0 2px 17px;font-size:10px;color:#95a3b5}.practice-mode>div{display:flex;gap:2px;padding:3px;background:#f1f5fa;border-radius:7px}.practice-mode button{padding:6px 10px;font-size:10px;color:#8c9bb0;border-radius:5px}.practice-mode button.selected{color:#4b86c9;background:white;box-shadow:0 1px 4px #324e7110}.practice-mode small{font-size:9px;color:#a2aebd;line-height:1.6}@media(max-width:700px){.practice-mode{gap:8px;margin-bottom:14px}.practice-mode small{flex-basis:100%;font-size:9px}}