/* ===== CSS Reset & Base ===== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{--primary:#2563eb;--primary-dark:#1d4ed8;--secondary:#0ea5e9;--bg:#f8fafc;--white:#fff;--text:#1e293b;--text-light:#64748b;--border:#e2e8f0;--radius:12px;--shadow:0 1px 3px rgba(0,0,0,.1);--shadow-md:0 4px 12px rgba(0,0,0,.08);--max-w:1200px;--nav-h:64px}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'Helvetica Neue',Arial,sans-serif;color:var(--text);background:var(--bg);line-height:1.7;font-size:16px}
a{color:var(--primary);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;height:auto;display:block}
ul,ol{padding-left:1.5rem}

/* ===== Utilities ===== */
.container{max-width:var(--max-w);margin:0 auto;padding:0 1rem}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);border:0}

/* ===== Navbar ===== */
.navbar{position:sticky;top:0;z-index:1000;background:var(--white);border-bottom:1px solid var(--border);box-shadow:var(--shadow)}
.nav-inner{max-width:var(--max-w);margin:0 auto;display:flex;align-items:center;justify-content:space-between;height:var(--nav-h);padding:0 1rem}
.nav-logo{font-size:1.4rem;font-weight:800;color:var(--primary);text-decoration:none;display:flex;align-items:center;gap:.4rem}
.nav-logo span{color:var(--secondary)}
.nav-links{display:flex;gap:.25rem;align-items:center}
.nav-links a{padding:.5rem .75rem;border-radius:8px;font-size:.9rem;font-weight:500;color:var(--text);text-decoration:none;transition:background .2s}
.nav-links a:hover,.nav-links a.active{background:#eff6ff;color:var(--primary)}
.hamburger{display:none;background:none;border:none;font-size:1.5rem;cursor:pointer;color:var(--text);padding:.25rem}

/* Mobile nav */
@media(max-width:768px){
  .hamburger{display:block}
  .nav-links{position:fixed;top:var(--nav-h);left:0;right:0;bottom:0;background:var(--white);flex-direction:column;padding:1.5rem;gap:.5rem;transform:translateX(100%);transition:transform .3s ease;overflow-y:auto;z-index:999}
  .nav-links.open{transform:translateX(0)}
  .nav-links a{font-size:1.1rem;padding:.75rem 1rem;width:100%;border-radius:10px}
}

/* ===== Hero ===== */
.hero{background:linear-gradient(135deg,#1e3a8a 0%,#2563eb 50%,#0ea5e9 100%);color:var(--white);padding:4rem 1rem;text-align:center}
.hero h1{font-size:2.5rem;font-weight:800;margin-bottom:.75rem}
.hero p{font-size:1.15rem;opacity:.9;max-width:600px;margin:0 auto 2rem}
.hero-btn{display:inline-block;background:var(--white);color:var(--primary);padding:.75rem 2rem;border-radius:50px;font-weight:700;font-size:1rem;transition:transform .2s,box-shadow .2s}
.hero-btn:hover{text-decoration:none;transform:translateY(-2px);box-shadow:0 4px 20px rgba(0,0,0,.2)}
@media(max-width:600px){.hero h1{font-size:1.8rem}.hero{padding:2.5rem 1rem}}

/* ===== Section ===== */
.section{padding:3rem 0}
.section-title{font-size:1.8rem;font-weight:700;margin-bottom:.5rem;text-align:center}
.section-sub{text-align:center;color:var(--text-light);margin-bottom:2rem;max-width:600px;margin-left:auto;margin-right:auto}

/* ===== Tool Grid ===== */
.tool-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:1.25rem}
.tool-card{background:var(--white);border:1px solid var(--border);border-radius:var(--radius);padding:1.5rem;transition:transform .2s,box-shadow .2s}
.tool-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-md)}
.tool-card h3{font-size:1.1rem;margin-bottom:.5rem}
.tool-card p{font-size:.88rem;color:var(--text-light);margin-bottom:.75rem}
.tool-card .card-link{font-size:.88rem;font-weight:600;color:var(--primary)}
.tool-icon{width:44px;height:44px;border-radius:10px;display:flex;align-items:center;justify-content:center;font-size:1.4rem;margin-bottom:.75rem}
.tool-icon.blue{background:#dbeafe;color:#2563eb}
.tool-icon.green{background:#dcfce7;color:#16a34a}
.tool-icon.orange{background:#ffedd5;color:#ea580c}
.tool-icon.purple{background:#f3e8ff;color:#9333ea}
.tool-icon.pink{background:#fce7f3;color:#db2777}
.tool-icon.cyan{background:#cffafe;color:#0891b2}
.tool-category{margin-bottom:2rem}
.tool-category h2{font-size:1.3rem;font-weight:700;margin-bottom:1rem;padding-bottom:.5rem;border-bottom:2px solid var(--border)}

/* ===== Article Grid ===== */
.article-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:1.5rem}
.article-card{background:var(--white);border:1px solid var(--border);border-radius:var(--radius);overflow:hidden;transition:transform .2s,box-shadow .2s}
.article-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-md)}
.article-card img{width:100%;height:180px;object-fit:cover}
.article-card .card-body{padding:1.25rem}
.article-card h3{font-size:1.05rem;margin-bottom:.4rem;line-height:1.4}
.article-card p{font-size:.85rem;color:var(--text-light);margin-bottom:.75rem;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}
.article-card .meta{font-size:.78rem;color:var(--text-light)}

/* ===== Tool Page ===== */
.tool-page{padding:2rem 0 3rem}
.tool-page h1{font-size:2rem;margin-bottom:.5rem}
.tool-desc{color:var(--text-light);margin-bottom:1.5rem;max-width:700px}
.tool-container{background:var(--white);border:1px solid var(--border);border-radius:var(--radius);padding:2rem;max-width:700px}
.tool-container label{display:block;font-weight:600;margin-bottom:.3rem;font-size:.9rem}
.tool-container input,.tool-container select{width:100%;padding:.6rem .75rem;border:1px solid var(--border);border-radius:8px;font-size:1rem;margin-bottom:1rem;transition:border-color .2s}
.tool-container input:focus,.tool-container select:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px rgba(37,99,235,.1)}
.tool-container .btn{background:var(--primary);color:var(--white);border:none;padding:.65rem 1.5rem;border-radius:8px;font-size:.95rem;font-weight:600;cursor:pointer;transition:background .2s}
.tool-container .btn:hover{background:var(--primary-dark)}
.tool-container .result{margin-top:1rem;padding:1rem;background:#f0f9ff;border:1px solid #bae6fd;border-radius:8px;font-size:1rem;display:none}
.tool-container .result.show{display:block}
.tool-container .result strong{color:var(--primary)}
.related-tools{margin-top:2.5rem}
.related-tools h3{font-size:1.2rem;margin-bottom:1rem}
.related-tools a{display:inline-block;margin:.25rem;padding:.4rem .9rem;background:var(--white);border:1px solid var(--border);border-radius:20px;font-size:.85rem}
.related-tools a:hover{background:#eff6ff;border-color:var(--primary)}
.breadcrumb{font-size:.85rem;color:var(--text-light);margin-bottom:1.5rem}
.breadcrumb a{color:var(--text-light)}
.breadcrumb a:hover{color:var(--primary)}

/* ===== Article Page ===== */
.article-page{padding:2rem 0 3rem}
.article-content{max-width:780px;margin:0 auto;background:var(--white);border-radius:var(--radius);padding:2rem;border:1px solid var(--border)}
.article-content h1{font-size:2rem;line-height:1.3;margin-bottom:.5rem}
.article-content .article-meta{color:var(--text-light);font-size:.9rem;margin-bottom:2rem;padding-bottom:1rem;border-bottom:1px solid var(--border)}
.article-content h2{font-size:1.5rem;margin-top:2rem;margin-bottom:.75rem}
.article-content h3{font-size:1.2rem;margin-top:1.5rem;margin-bottom:.5rem}
.article-content p{margin-bottom:1rem;line-height:1.8}
.article-content img{border-radius:8px;margin:1.5rem 0}
.article-content ul,.article-content ol{margin-bottom:1rem}
.article-content li{margin-bottom:.4rem}
.article-content a.tool-mention{background:#eff6ff;padding:.1rem .4rem;border-radius:4px;font-weight:500}
@media(max-width:600px){.article-content{padding:1.25rem}.article-content h1{font-size:1.5rem}}

/* ===== Static Pages ===== */
.static-page{padding:2rem 0 3rem}
.static-content{max-width:780px;margin:0 auto;background:var(--white);border-radius:var(--radius);padding:2rem;border:1px solid var(--border)}
.static-content h1{font-size:2rem;margin-bottom:1rem}
.static-content h2{font-size:1.4rem;margin-top:1.5rem;margin-bottom:.75rem}
.static-content p{margin-bottom:1rem;line-height:1.8}
.static-content ul,.static-content ol{margin-bottom:1rem}
.static-content li{margin-bottom:.3rem}

/* Contact form */
.contact-form input,.contact-form textarea,.contact-form select{width:100%;padding:.65rem .75rem;border:1px solid var(--border);border-radius:8px;font-size:1rem;margin-bottom:1rem;font-family:inherit}
.contact-form input:focus,.contact-form textarea:focus{outline:none;border-color:var(--primary);box-shadow:0 0 0 3px rgba(37,99,235,.1)}
.contact-form textarea{min-height:150px;resize:vertical}
.contact-form .btn{background:var(--primary);color:var(--white);border:none;padding:.7rem 2rem;border-radius:8px;font-size:1rem;font-weight:600;cursor:pointer}

/* ===== Footer ===== */
.footer{background:#1e293b;color:#cbd5e1;padding:2.5rem 0 1.5rem;margin-top:3rem}
.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:2rem;margin-bottom:2rem}
.footer h4{color:var(--white);font-size:1rem;margin-bottom:.75rem}
.footer p{font-size:.88rem;line-height:1.7}
.footer a{color:#94a3b8;font-size:.88rem;display:block;margin-bottom:.3rem}
.footer a:hover{color:var(--white)}
.footer-bottom{border-top:1px solid #334155;padding-top:1rem;font-size:.8rem;text-align:center;color:#64748b}
@media(max-width:600px){.footer-grid{grid-template-columns:1fr;gap:1.5rem}}

/* ===== 404 ===== */
.error-page{text-align:center;padding:4rem 1rem}
.error-page h1{font-size:5rem;color:var(--primary);font-weight:800}
.error-page h2{font-size:1.5rem;margin:1rem 0}
.error-page p{color:var(--text-light);margin-bottom:1.5rem}