*{margin:0;padding:0;box-sizing:border-box}
:root{--bg:#f7f8fa;--card:#fff;--primary:#2563eb;--primary-hover:#1d4ed8;--secondary:#6b7280;--secondary-hover:#4b5563;--border:#e5e7eb;--text:#1f2937;--heading:#111827;--muted:#6b7280;--error:#dc2626;--success:#16a34a;--code-bg:#fafbfc}
html{font-size:16px}
body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;background:var(--bg);color:var(--text);line-height:1.65}
.container{max-width:1100px;margin:0 auto;padding:24px 20px 60px}
.brand-header{display:flex;align-items:center;margin:12px 0 24px}
.brand-header a{font-size:18px;font-weight:700;color:var(--primary);text-decoration:none}
.brand-header a:hover{text-decoration:underline}
.brand-header .brand-desc{color:#666;margin-left:8px}
.back-link{display:inline-block;margin-bottom:20px;color:var(--primary);text-decoration:none;font-size:14px;font-weight:500}
.back-link:hover{text-decoration:underline}
h1{font-size:28px;line-height:1.2;margin-bottom:12px;color:var(--heading);font-weight:700}
h2{font-size:20px;line-height:1.3;margin:28px 0 12px;color:var(--heading);font-weight:600}
h3{font-size:16px;margin-bottom:6px;color:var(--heading)}
p{margin-bottom:12px}
.desc{color:var(--muted);margin-bottom:24px;font-size:15px}
.privacy-badge{display:inline-block;background:#ecfdf5;color:#065f46;font-size:12px;padding:2px 10px;border-radius:12px;font-weight:500;margin-left:8px;vertical-align:middle}
.tool-area{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-bottom:16px}
.tool-area.single{grid-template-columns:1fr}
.pane{background:var(--card);border:1px solid var(--border);border-radius:8px;padding:14px;box-shadow:0 1px 2px rgba(0,0,0,.04);transition:box-shadow .15s}
.pane:hover{box-shadow:0 2px 6px rgba(0,0,0,.06)}
.pane label{display:block;font-size:13px;font-weight:600;margin-bottom:8px;color:var(--secondary);text-transform:uppercase;letter-spacing:.03em}
textarea,.expr-input{width:100%;min-height:280px;font-family:'Consolas','Monaco','Courier New',monospace;font-size:13px;line-height:1.5;padding:10px;border:1px solid var(--border);border-radius:6px;resize:vertical;background:var(--code-bg);color:var(--text);outline:none;transition:border-color .15s}
textarea:focus,.expr-input:focus{border-color:var(--primary)}
.expr-input{min-height:48px;resize:none}
#output{background:var(--code-bg);color:#0f172a}
.tree-output{min-height:280px;max-height:480px;overflow:auto;padding:10px;background:var(--code-bg);border:1px solid var(--border);border-radius:6px;font-family:'Consolas','Monaco','Courier New',monospace;font-size:13px;line-height:1.6}
.tree-output details{margin-left:8px}
.tree-output details>summary{cursor:pointer;padding:1px 0;user-select:none}
.tree-output ul,.tree-output ol{list-style:none;margin-left:12px;padding-left:8px;border-left:1px dashed var(--border)}
.tree-output .key{color:#7c3aed;font-weight:600}
.tree-output .string{color:#16a34a}
.tree-output .number{color:#2563eb}
.tree-output .boolean{color:#ea580c}
.tree-output .null{color:#9ca3af}
.tree-output .object,.tree-output .array{color:var(--muted);font-size:12px;margin-left:4px}
.buttons{display:flex;gap:12px;align-items:center;margin-bottom:16px;flex-wrap:wrap}
button{padding:10px 24px;border:none;border-radius:6px;font-size:14px;font-weight:600;cursor:pointer;transition:background .15s;font-family:inherit}
.btn-primary{background:var(--primary);color:#fff}
.btn-primary:hover{background:var(--primary-hover)}
.btn-secondary{background:var(--secondary);color:#fff}
.btn-secondary:hover{background:var(--secondary-hover)}
#status{font-size:13px;margin-left:8px;font-weight:500}
.status-ok{color:var(--success)}
.status-error{color:var(--error)}
.related{display:flex;flex-wrap:wrap;gap:10px;margin-top:8px}
.related a{display:inline-block;padding:8px 14px;background:#fff;border:1px solid var(--border);border-radius:6px;color:var(--primary);text-decoration:none;font-size:13px;font-weight:500;transition:box-shadow .15s,border-color .15s}
.related a:hover{box-shadow:0 2px 6px rgba(0,0,0,.08);border-color:var(--primary)}
.tools-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:16px;margin-top:24px}
.tool-card{display:block;padding:20px;background:#fff;border:1px solid var(--border);border-radius:8px;text-decoration:none;color:var(--text);transition:box-shadow .15s,transform .15s,border-color .15s}
.tool-card:hover{box-shadow:0 4px 12px rgba(0,0,0,.08);transform:translateY(-2px);border-color:var(--primary)}
.tool-card h3{color:var(--primary);margin-bottom:6px;font-size:16px;font-weight:600}
.tool-card p{font-size:13px;color:var(--muted);margin:0;line-height:1.5}
.feature-list{padding-left:20px}
.feature-list li{margin-bottom:6px}
.feature-list li::marker{color:var(--primary)}
code{background:var(--code-bg);padding:2px 6px;border-radius:4px;font-size:13px;font-family:'Consolas','Monaco',monospace;border:1px solid var(--border)}
pre{background:var(--code-bg);padding:12px;border-radius:6px;overflow-x:auto;border:1px solid var(--border);margin-bottom:12px}
pre code{background:none;border:none;padding:0}
footer{margin-top:40px;padding-top:20px;border-top:1px solid var(--border);color:var(--muted);font-size:13px;text-align:center}
@media (max-width:768px){.tool-area{grid-template-columns:1fr}h1{font-size:24px}h2{font-size:18px}.container{padding:16px 12px 40px}textarea,.expr-input{min-height:200px}.tree-output{max-height:320px}.tools-grid{grid-template-columns:1fr}.buttons{flex-direction:column;align-items:stretch}button{width:100%}}

.ad-slot{min-height:15px;margin-top:40px;margin-bottom:32px}

/* ===== Floating topbar + language dropdown ===== */
.topbar{position:sticky;top:0;z-index:100;display:flex;align-items:center;gap:10px;flex-wrap:wrap;padding:10px 16px;background:#fff;border-bottom:1px solid #e4e8f0;box-shadow:0 1px 4px rgba(20,30,60,.05);}
.topbar a{color:#3b82f6;text-decoration:none;font-size:13px;font-weight:600;}
.topbar a:hover{text-decoration:underline;}
.topbar .divider{color:#d7deea;font-size:13px;}
.topbar .brand-name{font-weight:700;font-size:15px;color:#1f2430;letter-spacing:.3px;text-decoration:none;}
.topbar .brand-name span{color:#3b82f6;}
.spacer{flex:1;}
.lang-dropdown{position:relative;}
.lang-dropdown summary{list-style:none;cursor:pointer;font-size:13px;font-weight:600;color:#39435a;background:#fff;border:1px solid #dde3ee;border-radius:9px;padding:7px 12px;display:inline-flex;align-items:center;gap:6px;}
.lang-dropdown summary::-webkit-details-marker{display:none;}
.lang-dropdown summary::after{content:'\25BE';font-size:10px;color:#8b93a7;margin-left:2px;}
.lang-menu{position:absolute;right:0;top:calc(100% + 6px);background:#fff;border:1px solid #e4e8f0;border-radius:9px;box-shadow:0 6px 18px rgba(20,30,60,.12);overflow:hidden;min-width:140px;z-index:200;display:flex;flex-direction:column;}
.lang-menu a{display:block;padding:9px 14px;color:#39435a;text-decoration:none;font-size:13px;font-weight:500;}
.lang-menu a:hover{background:#f4f7fd;color:#3b82f6;}
.lang-menu a[aria-current="true"]{background:#eef4ff;color:#2563eb;font-weight:700;}
@media(max-width:768px){.topbar{padding:8px 12px;}.topbar .brand-name{font-size:14px;}}

/* Legal links (footer) */
.legal-links{margin-top:6px;font-size:12px}
.legal-links a{margin:0 5px}