:root{font-family:Inter,-apple-system,BlinkMacSystemFont,'PingFang SC','Microsoft YaHei',sans-serif;color:#203b37;background:#f7faf9;font-synthesis:none;--green:#087e70;--muted:#81938f;--line:#e6eeeb;--mint:#e9f5ef}*{box-sizing:border-box}body{margin:0}button,input,textarea{font:inherit}button,a{touch-action:manipulation}button{cursor:pointer}button{border:0;background:none;color:inherit}button:disabled{cursor:not-allowed;opacity:.45}a{color:inherit;text-decoration:none}button:focus-visible,a:focus-visible{outline:3px solid #70cbb0;outline-offset:3px}svg{vertical-align:middle}.app-layout{min-height:100dvh;display:grid;grid-template-columns:252px 1fr}.sidebar{padding:34px 22px 20px;background:#edf4f0;border-right:1px solid #e0eae5;display:flex;flex-direction:column;gap:28px}.brand{display:flex;align-items:center;gap:12px}.brand-mark{display:grid;place-items:center;background:var(--green);color:white;border-radius:13px;width:42px;height:42px;font-weight:700;font-size:23px}.brand strong{font-size:22px;letter-spacing:2px}.brand small{display:block;color:var(--muted);font-size:11px;letter-spacing:2px;margin-top:4px}.new-chat{background:var(--green);color:white;padding:13px 20px;border-radius:10px;text-align:left;font-size:15px}.side-label{font-size:12px;color:#8a9e95;padding:0 10px;letter-spacing:1px}.side-nav{display:grid;gap:7px}.side-nav a,.side-nav button{padding:13px;border-radius:9px;text-align:left;display:flex;align-items:center;gap:11px;font-size:14px}.side-nav .active{background:#dbeae3;color:#146e58;font-weight:600}.sidebar-bottom{margin-top:auto;border-top:1px solid #d9e5df;padding-top:18px;font-size:12px;color:#82928c}.sidebar-bottom a{display:block;margin-top:17px}.student-main{min-width:0;position:relative;display:flex;flex-direction:column;min-height:100dvh}.student-top{height:85px;display:flex;align-items:center;justify-content:space-between;padding:0 44px;border-bottom:1px solid 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var(--line);border-radius:14px;padding:22px 17px;text-align:left;transition:.2s}.quick-card:hover{transform:translateY(-3px);border-color:#a7cec0;box-shadow:0 10px 30px #0c70440b}.quick-card .quick-icon{background:#edf7f1;color:#48846f;width:36px;height:36px;border-radius:10px;display:grid;place-items:center;margin-bottom:20px}.quick-card b{font-size:15px;display:block;margin-bottom:9px}.quick-card small{font-size:12px;color:#90a098;line-height:1.6;display:block}.chat-footer{width:100%;max-width:860px;margin:0 auto;padding:0 40px 20px}.composer{border:1px solid #dce7e1;box-shadow:0 8px 32px #124f3606;background:white;border-radius:18px;padding:16px 18px}.composer textarea{border:0;outline:0;resize:none;background:transparent;width:100%;height:56px;color:#29463b;font-size:15px;line-height:1.6}.composer 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h1{font-size:27px}.welcome>p{font-size:14px;line-height:1.8}.hello-emblem{width:52px;height:52px;margin-bottom:22px}.quick-grid{grid-template-columns:1fr;gap:9px}.quick-card{display:grid;grid-template-columns:38px 1fr;gap:0 12px;padding:14px}.quick-card .quick-icon{grid-row:1/3;margin:0}.quick-card b{font-size:14px;margin-bottom:4px}.quick-card small{font-size:12px}.chat-footer{padding:0 16px max(18px,env(safe-area-inset-bottom))}.student-main{min-height:100dvh}.welcome{margin:auto}.mobile-only{display:initial}.campus-label{font-size:13px}.campus-label span{display:none}.footer-note{font-size:10px}.trust-line{font-size:11px;margin-top:18px}}