:root{--bg-color:#fff;--text-main:#333;--nav-border:#eee;--footer-text:#999}html.dark{--bg-color:#1a1a1a;--text-main:#dcdcdc;--nav-border:#333;--footer-text:#777}body,html{background-color:var(--bg-color);color:var(--text-main);margin:0;padding:0;transition:background-color .3s ease,color .3s ease}.app-layout{display:flex;flex-direction:column;font-family:sans-serif;margin:0 auto;max-width:900px;min-height:100vh;padding:20px}.main-header{border-bottom:1px solid var(--nav-border);margin-bottom:20px;padding-bottom:20px}.nav-container{align-items:center;display:flex;justify-content:space-between}.nav-item{color:inherit;font-weight:700;margin-right:15px;text-decoration:none}.theme-toggle{background:var(--nav-border);border:1px solid transparent;border-radius:20px;cursor:pointer;font-size:1.1rem;padding:5px 12px;transition:transform .2s}.theme-toggle:hover{transform:scale(1.1)}.page-body{flex:1}.main-footer{color:var(--footer-text);font-size:.8rem;margin-top:50px;padding-bottom:20px;text-align:center}.footer-records{display:flex;flex-wrap:wrap;gap:14px;justify-content:center;margin-top:8px}.footer-record{align-items:center;color:var(--footer-text);display:inline-flex;font-size:.75rem;gap:6px;text-decoration:none}.footer-record img{height:14px;opacity:.85;width:14px}.footer-record:hover{text-decoration:underline}