:root {
  --primary: #0d6e3d;
  --primary-dark: #0a5530;
  --bg: #ffffff;
  --bg-secondary: #e8f5ee;
  --card: #ffffff;
  --text: #0f172a;
  --text-secondary: #64748b;
  --border: #e2e8f0;
  --shadow: 0 1px 3px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 40px rgba(13,110,61,0.12);
  --radius: 16px;
  --gradient: radial-gradient(circle at top right, #0d6e3d, #0a5530, #064224);
}
[data-theme="dark"] {
  --primary: #34d399;
  --primary-dark: #10b981;
  --bg: #0f172a;
  --bg-secondary: #022c22;
  --card: #1e293b;
  --text: #f1f5f9;
  --text-secondary: #94a3b8;
  --border: #334155;
  --shadow: 0 1px 3px rgba(0,0,0,0.4);
  --shadow-lg: 0 10px 40px rgba(0,0,0,0.4);
}
*, *::before, *::after { margin:0; padding:0; box-sizing:border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  transition: background 0.3s, color 0.3s;
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* Header */
.header {
  background: rgba(255,255,255,0.8);
  border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 100;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}
[data-theme="dark"] .header { background: rgba(15,23,42,0.8); }
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 0; gap: 20px;
}
.logo { font-size: 1.6rem; font-weight: 800; color: var(--primary); letter-spacing: -0.5px; }
.logo span { color: var(--text); }
.search-box {
  flex: 1; max-width: 400px; position: relative;
}
.search-box input {
  width: 100%; padding: 10px 16px 10px 40px;
  border: 1px solid var(--border); border-radius: 8px;
  background: var(--bg-secondary); color: var(--text);
  font-size: 0.9rem;
}
.search-box input:focus { outline: none; border-color: var(--primary); }
.search-icon { position: absolute; left: 12px; top: 50%; transform: translateY(-50%); color: var(--text-secondary); }
.theme-toggle {
  background: none; border: 1px solid var(--border);
  padding: 10px 14px; border-radius: 8px; cursor: pointer;
  color: var(--text); font-size: 1.2rem;
  min-width: 44px; min-height: 44px; display: flex; align-items: center; justify-content: center;
}
.nav-menu { display: flex; align-items: center; gap: 6px; }
.nav-menu a {
  padding: 8px 14px; border-radius: 8px; font-size: 0.9rem;
  font-weight: 500; color: var(--text-secondary); transition: all 0.2s;
}
.nav-menu a:hover { background: var(--bg-secondary); color: var(--primary); text-decoration: none; }
@media (max-width: 768px) {
  .nav-menu { display: none; }
  .nav-menu.open { display: flex; flex-direction: column; position: absolute; top: 100%; left: 0; right: 0;
    background: var(--bg); border-bottom: 1px solid var(--border); padding: 12px; gap: 4px; }
  .nav-toggle { display: block !important; }
}
.nav-toggle { display: none; background: none; border: 1px solid var(--border);
  padding: 10px 14px; border-radius: 8px; cursor: pointer; color: var(--text); font-size: 1.2rem;
  min-width: 44px; min-height: 44px; display: flex; align-items: center; justify-content: center; }

/* Categories */
.categories-bar {
  display: flex; gap: 8px; overflow-x: auto; padding: 16px 0;
  -webkit-overflow-scrolling: touch;
}
.cat-btn {
  white-space: nowrap; padding: 10px 20px;
  background: var(--bg-secondary); border: 1px solid var(--border);
  border-radius: 20px; color: var(--text-secondary); cursor: pointer;
  font-weight: 500; transition: all 0.2s; font-size: 0.9rem;
  min-height: 44px; display: inline-flex; align-items: center;
}
.cat-btn:hover, .cat-btn.active { background: var(--primary); color: #fff; border-color: var(--primary); }

/* Hero */
.hero {
  text-align: center; padding: 70px 0 30px;
  background: var(--gradient); -webkit-background-clip: text;
  -webkit-text-fill-color: transparent; background-clip: text;
}
.hero h1 { font-size: 3rem; font-weight: 900; margin-bottom: 16px; line-height: 1.1; }
.hero h1 span { -webkit-text-fill-color: transparent; }
.hero p { color: var(--text-secondary); font-size: 1.15rem; max-width: 600px; margin: 0 auto; -webkit-text-fill-color: initial; }

/* Stats bar */
.stats-bar {
  display: flex; justify-content: center; align-items: center; gap: 24px;
  padding: 20px 0; margin-bottom: 24px; flex-wrap: wrap;
}
.stat-item { text-align: center; }
.stat-num { display: block; font-size: 1.5rem; font-weight: 800; color: var(--primary); }
.stat-text { font-size: 0.8rem; color: var(--text-secondary); text-transform: uppercase; letter-spacing: 0.5px; }
.stat-divider { width: 1px; height: 32px; background: var(--border); }
@media (max-width: 480px) {
  .stats-bar { gap: 16px; }
  .stat-num { font-size: 1.2rem; }
}

/* Tools Grid */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px; padding-bottom: 60px;
}
.tool-card {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 28px;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1); cursor: pointer;
  box-shadow: var(--shadow); position: relative; overflow: hidden;
}
.tool-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: var(--gradient); transform: scaleX(0); transition: transform 0.3s;
  transform-origin: left;
}
.tool-card:hover {
  transform: translateY(-4px); box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}
.tool-card:hover::before { transform: scaleX(1); }
.tool-icon { font-size: 2.2rem; margin-bottom: 14px; display: inline-block; transition: transform 0.3s; }
.tool-card:hover .tool-icon { transform: scale(1.15) rotate(-5deg); }
.tool-card h3 { font-size: 1.1rem; margin-bottom: 6px; font-weight: 700; }
.tool-card p { color: var(--text-secondary); font-size: 0.875rem; line-height: 1.5; }
.favorite-btn { position: absolute; top: 12px; right: 12px; background: none; border: none;
  font-size: 1.3rem; cursor: pointer; opacity: 0.3; transition: all 0.2s; padding: 8px;
  min-width: 44px; min-height: 44px; display: flex; align-items: center; justify-content: center; }
.favorite-btn:hover { opacity: 1; transform: scale(1.2); }
.favorite-btn.active { opacity: 1; }

/* Tool Page */
.tool-page { padding: 32px 0 60px; }
.tool-header { margin-bottom: 28px; }
.tool-header h1 { font-size: 2.2rem; font-weight: 800; margin-bottom: 8px; background: var(--gradient);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.tool-header p { color: var(--text-secondary); font-size: 1.05rem; }
.tool-box {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 36px;
  box-shadow: var(--shadow-lg); max-width: 650px; margin-bottom: 32px;
  transition: box-shadow 0.3s;
}
.tool-box:hover { box-shadow: 0 12px 48px rgba(13,110,61,0.15); }
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-weight: 600; margin-bottom: 6px; font-size: 0.9rem; }
.form-group input, .form-group select, .form-group textarea {
  width: 100%; padding: 10px 14px;
  border: 1px solid var(--border); border-radius: 8px;
  background: var(--bg); color: var(--text); font-size: 1rem;
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
  outline: none; border-color: var(--primary);
}
.form-group textarea { min-height: 100px; resize: vertical; font-family: monospace; }
.btn {
  padding: 12px 28px; background: var(--gradient); color: #fff;
  border: none; border-radius: 10px; cursor: pointer; font-weight: 600;
  font-size: 1rem; transition: all 0.3s;   box-shadow: 0 4px 15px rgba(13,110,61,0.3);
}
.btn:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(13,110,61,0.4); }
.btn-secondary { background: var(--bg-secondary); color: var(--text); box-shadow: none; border: 1px solid var(--border); }
.btn-secondary:hover { border-color: var(--primary); color: var(--primary); }
.btn-group { display: flex; gap: 10px; flex-wrap: wrap; }
.btn-block { width: 100%; }
.result-box {
  background: var(--bg-secondary); border: 1px solid var(--border);
  border-radius: 8px; padding: 16px; margin-top: 16px;
  font-size: 1.1rem; font-weight: 600; text-align: center;
}
.result-box .value { color: var(--primary); font-size: 1.5rem; }
.result-box .label { color: var(--text-secondary); font-size: 0.85rem; font-weight: 400; }
.result-box .desc { font-size: 0.9rem; font-weight: 400; color: var(--text-secondary); margin-top: 4px; }

/* Article / SEO */
.article { max-width: 800px; margin: 40px auto; }
.article h2 { font-size: 1.5rem; margin: 24px 0 12px; }
.article p { color: var(--text-secondary); margin-bottom: 12px; }
.article ul { color: var(--text-secondary); padding-left: 20px; margin-bottom: 12px; }
.article ul li { margin-bottom: 6px; }

/* Footer */
.footer {
  border-top: 1px solid var(--border); padding: 32px 0;
  text-align: center; color: var(--text-secondary); font-size: 0.85rem;
}
.footer-links {
  display: flex; justify-content: center; gap: 24px; margin-bottom: 12px;
  flex-wrap: wrap;
}
.footer-links a {
  color: var(--text-secondary); font-size: 0.875rem;
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--primary); }
.partner-links {
  display: flex; justify-content: center; align-items: center; gap: 16px;
  margin-bottom: 16px; flex-wrap: wrap; font-size: 0.8rem;
}
.partner-links span { color: var(--text-secondary); }
.partner-links a {
  color: var(--text-secondary); padding: 4px 12px;
  border: 1px solid var(--border); border-radius: 16px;
  transition: all 0.2s;
}
.partner-links a:hover {
  color: var(--primary); border-color: var(--primary);
  background: rgba(13,110,61,0.05);
}

/* Breadcrumb */
.breadcrumb { display: flex; gap: 8px; margin-bottom: 16px; font-size: 0.85rem; color: var(--text-secondary); }
.breadcrumb a { color: var(--text-secondary); }
.breadcrumb a:hover { color: var(--primary); }

/* Responsive */
@media (max-width: 768px) {
  .hero h1 { font-size: 1.8rem; }
  .hero p { font-size: 1rem; }
  .tools-grid { grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); }
  .tool-box { padding: 20px; }
  .header-inner { flex-wrap: wrap; }
  .search-box { order: 3; flex: 100%; max-width: 100%; }
}
@media (max-width: 480px) {
  .tools-grid { grid-template-columns: 1fr; }
  .row .form-group { min-width: 100%; }
}

/* Safe area for notch phones */
@supports (padding: env(safe-area-inset-top)) {
  .header { padding-top: env(safe-area-inset-top); }
  .footer { padding-bottom: env(safe-area-inset-bottom); }
}

/* Prevent horizontal overflow */
html { overflow-x: hidden; }

/* Smooth iOS scrolling */
.output-box, .ping-log, .kb-wrap {
  -webkit-overflow-scrolling: touch;
}

/* Row for multi-column forms */
.row { display: flex; gap: 12px; flex-wrap: wrap; }
.row .form-group { flex: 1; min-width: 200px; }

/* Copy button */
.copy-btn {
  background: var(--bg-secondary); border: 1px solid var(--border);
  padding: 10px 20px; border-radius: 8px; cursor: pointer;
  color: var(--text); font-size: 0.875rem; margin-top: 12px;
  transition: all 0.2s; min-height: 44px; display: inline-flex; align-items: center;
}
.copy-btn:hover { border-color: var(--primary); color: var(--primary); transform: translateY(-1px); }

/* Output area */
.output-box {
  background: var(--bg-secondary); border: 1px solid var(--border);
  border-radius: 8px; padding: 16px; margin-top: 16px;
  font-family: monospace; white-space: pre-wrap; word-break: break-all;
  font-size: 0.9rem; min-height: 50px;
}

/* Tool page description */
.tool-desc { margin-bottom: 24px; color: var(--text-secondary); }

/* Filter / sort */
.filter-bar { display: flex; gap: 8px; margin-bottom: 24px; flex-wrap: wrap; }
.filter-btn {
  padding: 10px 18px; border: 1px solid var(--border);
  border-radius: 16px; background: var(--bg); color: var(--text-secondary);
  cursor: pointer; font-size: 0.85rem; transition: all 0.2s;
  min-height: 44px; display: inline-flex; align-items: center;
}
.filter-btn:hover, .filter-btn.active { background: var(--primary); color: #fff; border-color: var(--primary); }

/* Ad placeholder */
.ad-placeholder {
  background: var(--bg-secondary); border: 1px solid var(--border);
  border-radius: 8px; padding: 60px 20px; text-align: center;
  color: var(--text-secondary); font-size: 0.85rem; margin: 16px 0;
}

/* Skip link */
.skip-link {
  position: absolute; left: -9999px; z-index: 999;
  padding: 8px 16px; background: var(--primary); color: #fff;
  font-weight: 600; border-radius: 4px;
}
.skip-link:focus { left: 10px; top: 10px; }

/* Error box */
.error-box {
  background: #fef2f2; border: 1px solid #fecaca; border-radius: 8px;
  padding: 12px 16px; margin-top: 12px; color: #dc2626; font-size: 0.9rem;
}
[data-theme="dark"] .error-box { background: #450a0a; border-color: #7f1d1d; color: #fca5a5; }

/* Text helpers */
.text-success { color: #22c55e; }
.text-error { color: #ef4444; }

/* Form focus animation */
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
  outline: none; border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(13,110,61,0.15);
}

/* Color preview */
.color-preview {
  width: 100%; height: 80px; border-radius: 12px; margin-bottom: 20px;
  border: 2px solid var(--border); transition: background 0.3s;
}

/* Contact grid */
.contact-grid {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px; margin-bottom: 20px;
}
.contact-item {
  text-align: center; padding: 28px 20px;
  background: var(--bg-secondary); border-radius: 12px;
  border: 1px solid var(--border); transition: all 0.3s;
}
.contact-item:hover {
  border-color: var(--primary); transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(13,110,61,0.15);
}
.contact-icon { font-size: 2.5rem; margin-bottom: 12px; }
.contact-item h3 { font-size: 1.1rem; margin-bottom: 6px; }
.contact-item p { color: var(--text-secondary); font-size: 0.875rem; margin-bottom: 10px; }

/* Related Tools */
.related-tools { margin-top: 40px; padding-top: 32px; border-top: 1px solid var(--border); }
.related-tools h2 { font-size: 1.3rem; font-weight: 700; margin-bottom: 16px; color: var(--text); }
.related-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 12px; }
.related-card { display: flex; align-items: center; gap: 12px; padding: 14px 16px; background: var(--bg-secondary); border: 1px solid var(--border); border-radius: 10px; text-decoration: none; color: var(--text); transition: all 0.2s; }
.related-card:hover { border-color: var(--primary); background: var(--card); text-decoration: none; transform: translateY(-2px); box-shadow: var(--shadow); }
.related-card .icon { font-size: 1.5rem; flex-shrink: 0; }
.related-card .info h3 { font-size: 0.9rem; font-weight: 600; margin-bottom: 2px; }
.related-card .info p { font-size: 0.75rem; color: var(--text-secondary); margin: 0; }
@media (max-width: 480px) { .related-grid { grid-template-columns: 1fr; } }