:root{font-family:"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;color:#172f32;background:#f5f8f7;--accent:#086b61;--muted:#536a6c;--border:#d8e3df}*{box-sizing:border-box}body{margin:0;min-height:100dvh;display:flex;flex-direction:column}header{max-width:1100px;width:100%;margin:0 auto;padding:28px 40px;display:flex;justify-content:space-between;align-items:center}.brand{font-weight:750;font-size:19px;color:inherit;text-decoration:none}.domain{font-size:13px;color:var(--muted);font-family:Consolas,monospace}main{max-width:880px;width:100%;margin:36px auto 48px;padding:0 40px;flex:1}.eyebrow{font-size:14px;color:var(--accent);margin:0 0 12px;font-weight:600}h1{font-size:clamp(30px,4vw,44px);letter-spacing:-1px;line-height:1.25;margin:0 0 15px;font-weight:750}.subtitle{color:var(--muted);font-size:16px;line-height:1.8;margin:0 0 32px}.receiver{border:1px solid var(--border);background:white;border-radius:14px;overflow:hidden;box-shadow:0 8px 32px #16392c06}.toolbar{display:flex;justify-content:space-between;gap:20px;align-items:center;padding:19px 24px;border-bottom:1px solid #edf1ef;color:var(--muted);font-size:13px}#state{font-weight:600;color:var(--accent)}textarea{display:block;width:100%;min-height:300px;max-height:60vh;border:0;resize:vertical;background:white;padding:24px;font:16px/1.85 "Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;color:#172f32;tab-size:4}textarea::placeholder{color:#657d7a}textarea:focus{outline:2px solid var(--accent);outline-offset:-3px}.actions{padding:16px 24px;display:flex;gap:20px;justify-content:space-between;align-items:center;border-top:1px solid #edf1ef}.actions span{font-size:12px;color:var(--muted);line-height:1.6}button{border:0;border-radius:8px;background:var(--accent);color:white;padding:13px 26px;font-family:inherit;font-size:14px;font-weight:600;line-height:1.4;white-space:nowrap;cursor:pointer;min-height:46px;transition:background .15s}button:hover{background:#054e47}button:disabled{background:#e4eae7;color:#5b6e66;cursor:default}button:focus-visible,a:focus-visible{outline:3px solid #318c80;outline-offset:4px}.below{display:flex;gap:12px;justify-content:space-between;align-items:center;margin-top:14px}#feedback{font-size:13px;color:var(--muted);line-height:1.6;margin:0}.text-button{padding:10px 0;background:transparent;color:var(--accent);min-height:44px}.text-button:hover{background:transparent;text-decoration:underline}.notice{color:var(--muted);font-size:12px;line-height:1.7;margin-top:28px}footer{max-width:1100px;width:100%;margin:0 auto;padding:20px 40px 30px;font-size:12px;color:var(--muted)}.sr-only{position:absolute;width:1px;height:1px;padding:0;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}@media(max-width:600px){header{padding:24px}.domain{font-size:11px}main{padding:0 24px;margin-top:24px}.subtitle{font-size:14px}.toolbar,.actions{padding:16px}textarea{padding:20px 16px;min-height:320px;font-size:16px}button{padding:13px 20px}.actions{gap:12px}footer{padding:20px 24px}.notice{margin-top:24px}}