:root{--red:#b51f2b;--red-dark:#8d1721;--ink:#25292d;--muted:#626b74;--line:#dce1e6;--paper:#f6f8fa;--panel:#f0f3f6;--white:#fff;--soft:#f9ecec;--green:#326454}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:70px}
body{margin:0;background:var(--paper);color:var(--ink);font:14px/1.75 "Segoe UI","PingFang SC","Microsoft YaHei",sans-serif}
button,textarea{font:inherit}button{cursor:pointer}a{color:inherit;text-underline-offset:3px}button,a,input{touch-action:manipulation}
button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #d65b4e;outline-offset:3px}
button:disabled{cursor:default;opacity:.4}[hidden]{display:none!important}
.skip{position:fixed;top:-100px;left:260px;z-index:100;background:white;padding:10px}.skip:focus{top:10px}
.sidebar{position:fixed;inset:0 auto 0 0;width:246px;z-index:30;background:var(--panel);border-right:1px solid var(--line);display:flex;flex-direction:column;padding:20px 14px 14px}
.brand{display:flex;align-items:center;gap:10px;text-decoration:none;font-size:19px;font-weight:700;padding:0 9px 16px}
.brand-mark{display:grid;place-items:center;width:34px;height:34px;border-radius:8px;background:var(--red);color:#fff;font:700 23px/1 serif}
.brand small{display:block;font-size:10px;letter-spacing:.05em;color:var(--muted);font-weight:400}
.nav-caption{display:flex;justify-content:space-between;font-size:11px;color:var(--muted);padding:11px 10px 4px;border-top:1px solid var(--line)}
#navigation{overflow-y:auto;flex:1;scrollbar-width:thin;padding-bottom:10px}
.nav-group{margin-bottom:8px}.nav-label{font-size:11px;color:#7a8188;padding:10px 10px 4px}
.nav-item{display:flex;align-items:center;gap:7px;padding:7px 9px;border-radius:7px;text-decoration:none;font-size:12px;line-height:1.5;min-height:33px;border:1px solid transparent;margin:1px 0}
.nav-num{font-size:10px;font-variant-numeric:tabular-nums;width:25px;flex:none;color:#7d848b}
.nav-item:hover{background:#fff}.nav-item[aria-current="step"]{background:#fff;border-color:var(--line);color:var(--red);font-weight:600}
.nav-item[aria-current="step"] .nav-num{color:var(--red)}.nav-done{margin-left:auto;color:var(--green)}
.sidebar-end{border-top:1px solid var(--line);padding:12px 8px 0;font-size:10px;color:#7c8389;line-height:1.8}
.sidebar-end small{display:block;font-size:10px;margin-left:11px}.status-dot{display:inline-block;width:4px;height:4px;background:#8d9c8f;border-radius:50%;margin-right:7px}
.workspace{margin-left:246px}.topbar{height:51px;display:flex;align-items:center;justify-content:space-between;padding:0 28px;border-bottom:1px solid var(--line);background:var(--paper);gap:12px}
.topbar>span{font-size:12px;color:#7a8289}.topbar strong{font-weight:500;color:#3a4249}.topbar>a{font-size:12px;text-decoration:none}.topbar>a:hover{color:var(--red)}.menu-button{display:none}
main{max-width:1100px;margin:auto;padding:20px 28px 0}.work-area{margin:0}.section-heading{display:flex;align-items:center;justify-content:space-between;gap:15px;font-size:12px;color:var(--muted);margin-bottom:10px}
.local-progress{font-size:11px;font-variant-numeric:tabular-nums;color:#7c848c}
#chapter{background:#fff;border:1px solid var(--line);border-radius:11px;overflow:hidden;outline:none}
.chapter-head{display:flex;align-items:flex-start;justify-content:space-between;gap:16px;padding:19px 22px 0}
.chapter-head h1{display:flex;align-items:center;flex-wrap:wrap;gap:10px;font-size:19px;line-height:1.5;font-weight:650;margin:0;min-width:0}
.chapter-index{display:inline-block;background:var(--red);color:#fff;border-radius:6px;font-size:11px;padding:2px 8px;white-space:nowrap;font-weight:600}
.checkpoint{display:flex;align-items:center;gap:6px;font-size:11px;white-space:nowrap;color:var(--muted);cursor:pointer;padding-top:4px}
.checkpoint input{width:14px;height:14px;margin:0;accent-color:var(--green);cursor:pointer}
.chapter-body{padding:8px 22px 19px}.action-copy{font-size:13px;color:var(--muted);margin:0 0 12px}
.outputs-box{display:flex;align-items:baseline;gap:11px;border:1px solid var(--line);background:var(--panel);border-radius:7px;padding:9px 12px;font-size:12px;margin-bottom:12px}
.outputs-box>b{color:var(--green);white-space:nowrap}.outputs{list-style:none;padding:0;margin:0;display:flex;flex-wrap:wrap;gap:2px 14px}.outputs li{position:relative;padding-left:10px}.outputs li:before{content:"·";position:absolute;left:0;color:#8a9299}
.version-note{font-size:11px;color:#867047;margin:0 0 12px;line-height:1.8}.version-note a{margin-left:6px;overflow-wrap:anywhere}
.prompt-box{border:1px solid var(--line);border-left:3px solid var(--red);border-radius:8px;background:var(--panel);overflow:hidden}
.prompt-top{display:flex;justify-content:space-between;align-items:center;gap:12px;padding:9px 13px 0}.prompt-top b{font-size:11px;font-weight:500;color:var(--muted)}
.copy-button{border:1px solid var(--line);background:#fff;color:var(--ink);border-radius:6px;padding:4px 11px;font-size:11px;white-space:nowrap}.copy-button:hover{border-color:var(--red);color:var(--red);background:#fcf4f4}
.prompt-text{font:13px/1.8 ui-monospace,SFMono-Regular,Consolas,"Microsoft YaHei",monospace;white-space:pre-wrap;overflow-wrap:anywhere;margin:0;padding:11px 14px 15px}
.quality{margin-top:16px}.quality h2{font-size:12px;font-weight:600;margin:0 0 5px}.quality ul{padding-left:18px;margin:0}.quality li{font-size:12px;color:var(--muted);margin:3px 0;line-height:1.8}
.chapter-footer{display:flex;justify-content:space-between;align-items:center;gap:16px;border-top:1px solid var(--line);padding:12px 22px}
.step-button{border:1px solid var(--line);border-radius:6px;padding:5px 10px;background:#fff;color:#626b74;font-size:11px}.step-button:hover:enabled{border-color:#b8a1a3;background:#fcf7f7}.step-next{color:var(--red)}
.page-footer{margin:17px 0 20px;font-size:10px;color:#899198}
#toast{position:fixed;left:calc(50% + 123px);bottom:22px;transform:translate(-50%,15px);padding:9px 17px;background:#2e3431;color:#fff;border-radius:8px;font-size:12px;opacity:0;pointer-events:none;transition:transform .15s,opacity .15s;z-index:80;max-width:90vw}#toast.show{opacity:1;transform:translate(-50%,0)}
@media(max-width:1100px){.sidebar{width:224px;padding:18px 11px 12px}.workspace{margin-left:224px}.topbar{padding:0 22px}main{padding:18px 22px 0}#toast{left:calc(50% + 112px)}}
@media(max-width:820px){.sidebar{transform:translateX(-100%);transition:transform .18s;width:258px;padding:22px 15px;z-index:60}.sidebar.open{transform:translateX(0)}.workspace{margin-left:0}.menu-button{display:block;border:1px solid var(--line);border-radius:6px;background:#fff;font-size:16px;line-height:1;padding:7px;color:#5b6269}.topbar{height:51px;padding:0 14px;position:sticky;top:0;z-index:20;background:var(--panel)}.topbar>span{margin-right:auto;font-size:11px}.topbar>a{font-size:11px}main{padding:16px 18px 0}#toast{left:50%}#menu-overlay{display:block;position:fixed;inset:0;background:#1e243966;z-index:50}.skip{left:14px}}
@media(max-width:540px){main{padding:13px 12px 0}.topbar{gap:8px;padding:0 11px}.topbar>span{font-size:10px}.topbar>a{font-size:10px}.section-heading{font-size:11px;margin-bottom:8px}.local-progress{font-size:10px}.chapter-head{padding:15px 15px 0;gap:8px}.chapter-head h1{font-size:17px;gap:7px}.chapter-index{font-size:10px;padding:2px 6px}.checkpoint{font-size:10px;padding-top:5px;gap:4px}.checkpoint input{width:13px;height:13px}.chapter-body{padding:8px 15px 16px}.action-copy{font-size:12px;margin-bottom:10px}.outputs-box{font-size:11px;padding:8px 10px;gap:8px}.outputs{display:block}.outputs li{margin:2px 0}.version-note{font-size:10px}.prompt-top{padding:8px 10px 0}.prompt-text{font-size:12px;line-height:1.8;padding:10px 11px 13px}.quality{margin-top:14px}.quality h2{font-size:11px}.quality li{font-size:11px;line-height:1.9}.chapter-footer{padding:10px 15px;gap:10px}.step-button{font-size:10px;padding:5px 8px;max-width:50%;white-space:normal;text-align:left}.step-next{text-align:right}.page-footer{font-size:9px;margin:13px 0 16px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important}}