:root{--bg:#fbfcfe;--muted:#44566b;--accent:#0b78b6;--accent2:#7c3aed;--card:#ffffff;--finance:#0f6cc9;--health:#ff6b35;--text:#6c5ce7;--dev:#00b894}
*{box-sizing:border-box}
body{margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Inter,Arial;background:var(--bg);color:#0b2633}
.wrap{max-width:980px;margin:20px auto;padding:18px}
body.sidebar-open{margin-left:280px}
.site-header{background:#fff;border-bottom:1px solid #eef3f7;position:sticky;top:0;z-index:1000;width:100%}
.header-top{display:flex;align-items:center;justify-content:space-between;padding:14px 18px;max-width:100%;margin:0 auto;position:fixed;}
.brand{font-weight:700;color:var(--accent);text-decoration:none;font-size:15px;white-space:nowrap}
.menu-toggle{background:none;border:none;cursor:pointer;display:flex;flex-direction:column;gap:5px;padding:8px;border-radius:6px;transition:all 0.3s}
.menu-toggle span{width:24px;height:2px;background:var(--accent);border-radius:2px;transition:all 0.3s}
.menu-toggle.active span:nth-child(1){transform:rotate(45deg) translate(10px,10px)}
.menu-toggle.active span:nth-child(2){opacity:0}
.menu-toggle.active span:nth-child(3){transform:rotate(-45deg) translate(7px,-7px)}
h1{font-size:22px;margin-top:10px}
.lede{color:var(--muted);margin-bottom:16px}
.cards{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}
.card{background:var(--card);border-radius:10px;padding:16px;border:1px solid #eef3f7}
.card h2{margin:0 0 8px}
.btn{display:inline-block;padding:10px 12px;border-radius:8px;background:linear-gradient(90deg,var(--accent),var(--accent2));color:#fff;text-decoration:none;border:none;cursor:pointer}
.content-card{padding:18px;background:#fff;border-radius:10px;border:1px solid #eef3f7;margin-top:18px}
.form-row{margin-top:12px}
.form-row.two{display:flex;gap:12px}
label{display:block;color:var(--muted);font-size:14px}
input[type=number], input[type=date], select{width:100%;padding:10px;border-radius:8px;border:1px solid #e6eef3;margin-top:8px}
.actions{margin-top:12px;display:flex;gap:8px}
.btn.alt{background:#203a44}
.result{margin-top:12px;padding:12px;border-radius:8px;background:#f4f8fb;border:1px solid #eaf3f8}
.chart-wrap{height:260px;margin-top:12px}
.tool-card h1{margin:0}
.howto{margin-top:18px;color:var(--muted)}
.site-footer{border-top:1px solid #eef3f7;margin-top:24px;background:#fff}
.site-footer .wrap{padding:12px;text-align:center}
.two-column{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:12px 0}
.code-editor{width:100%;padding:10px;border-radius:8px;border:1px solid #e6eef3;font-family:'Courier New',monospace;font-size:13px;resize:vertical;min-height:150px}
.small{font-size:12px;opacity:0.8}
ul{margin:8px 0;padding-left:20px}
ul li{margin:6px 0}
.sidebar-menu{position:fixed;left:0;top:0;width:265px;height:100vh;border-right:1px solid #eef3f7;transform:translateX(0);transition:transform 0.3s ease;z-index:999;overflow:auto}
.sidebar-menu.active{transform:translateX(0)}
.sidebar-close{position:absolute;top:12px;right:18px;background:none;border:none;cursor:pointer;font-size:24px;color:#44566b;transition:color 0.2s}
.sidebar-close:hover{color:var(--accent)}
.menu-category{padding:16px 0;border-bottom:1px solid #eef3f7}
.menu-category:first-child{border-top:1px solid #eef3f7}
.menu-category-title{font-weight:700;font-size:12px;text-transform:uppercase;color:#44566b;padding:8px 18px;display:flex;align-items:center;gap:8px}
.menu-category-icon{font-size:16px}
.menu-category a{display:block;padding:10px 28px;color:#1b4b62;text-decoration:none;font-size:14px;transition:all 0.2s}
.menu-category a:hover{background:rgba(11,120,182,0.08);color:var(--accent);border-left:3px solid var(--accent);padding-left:25px}
.sidebar-overlay{position:fixed;left:0;top:0;right:0;bottom:0;background:rgba(0,0,0,0.5);opacity:0;visibility:hidden;transition:all 0.3s;z-index:998}
.sidebar-overlay.active{opacity:1;visibility:visible}
@media(max-width:768px){
  .menu-toggle{display:flex;padding:5px 8px}
}
@media(max-width:780px){
  .cards{grid-template-columns:1fr}
  .form-row.two{flex-direction:column}
  .two-column{grid-template-columns:1fr}
}
@media(max-width:480px){
  .wrap{padding:12px;margin:10px auto}
}