*{box-sizing:border-box}body{margin:0;font-family:Arial,Noto Sans JP,sans-serif;background:#f6f7f9;color:#17202a}a{text-decoration:none;color:inherit}button,input,textarea{font:inherit}.shell{max-width:1180px;margin:auto;display:grid;grid-template-columns:220px minmax(0,640px) 280px;gap:18px}.card{background:#fff;border:1px solid #e5e7eb;border-radius:14px;padding:16px}.nav{position:sticky;top:0;height:100vh;padding:24px 8px}.nav a{display:block;padding:12px;border-radius:10px}.nav a.active{font-weight:700;background:#eef2ff}.feed{padding:18px 0}.composer textarea{width:100%;min-height:90px;border:0;resize:vertical;outline:0}.tweet{margin-top:12px}.meta{color:#667085;font-size:13px}.actions{display:flex;gap:18px;margin-top:12px}.right{padding-top:18px}.auth{max-width:440px;margin:8vh auto}.auth input,.auth textarea{width:100%;padding:12px;margin:7px 0;border:1px solid #ddd;border-radius:9px}.primary{border:0;border-radius:999px;padding:10px 18px;background:#111827;color:#fff;cursor:pointer}@media(max-width:900px){.shell{grid-template-columns:70px 1fr}.right,.nav .label{display:none}}@media(max-width:650px){.shell{display:block}.nav{position:fixed;z-index:3;bottom:0;top:auto;width:100%;height:auto;background:#fff;display:flex;justify-content:space-around;border-top:1px solid #ddd}.nav a{display:inline-block}.feed{padding:10px 10px 80px}}.nav-button{display:block;width:100%;text-align:left;padding:12px;border:0;background:transparent;border-radius:10px;cursor:pointer}.tweet img,.tweet video{max-width:48%;border-radius:12px;margin:2px}.list-row{padding:12px 0;border-bottom:1px solid #eee}.error{color:#b42318}.card input{padding:10px;border:1px solid #ddd;border-radius:9px;max-width:100%}