:root {
  --bg: #0a0e16;
  --bg-soft: #0f1522;
  --surface: #141b2b;
  --surface-2: #1a2235;
  --border: #243049;
  --border-soft: #1c263b;
  --text: #e6ecf5;
  --text-dim: #8b97ad;
  --text-faint: #5b6680;
  --accent: #00d9ff;
  --accent-glow: rgba(0, 217, 255, 0.15);

  --cat-web: #00d9ff;
  --cat-forensics: #a855f7;
  --cat-crypto: #f59e0b;
  --cat-pwn: #f43f5e;

  --d1: #34d399;
  --d2: #fbbf24;
  --d3: #f43f5e;

  --radius: 14px;
  --radius-sm: 8px;
  --mono: 'JetBrains Mono', ui-monospace, 'SF Mono', Menlo, Consolas, monospace;
  --sans: 'Noto Sans JP', system-ui, -apple-system, sans-serif;
  --shadow: 0 8px 30px rgba(0, 0, 0, 0.4);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

.bg-grid {
  position: fixed;
  inset: 0;
  z-index: 0;
  background-image:
    linear-gradient(var(--border-soft) 1px, transparent 1px),
    linear-gradient(90deg, var(--border-soft) 1px, transparent 1px);
  background-size: 44px 44px;
  opacity: 0.25;
  mask-image: radial-gradient(ellipse 80% 60% at 50% 0%, #000 30%, transparent 80%);
  pointer-events: none;
}

.container {
  width: min(1180px, 92vw);
  margin-inline: auto;
  position: relative;
  z-index: 1;
}

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(10, 14, 22, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px 0;
  flex-wrap: wrap;
}

.brand { display: flex; align-items: center; gap: 14px; }

.brand-mark {
  font-family: var(--mono);
  font-weight: 700;
  font-size: 26px;
  color: var(--accent);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 6px 12px;
  box-shadow: 0 0 18px var(--accent-glow);
  animation: blink 2.4s steps(1) infinite;
}

@keyframes blink { 0%, 92% { opacity: 1; } 96%, 100% { opacity: 0.55; } }

.brand-text h1 {
  font-family: var(--mono);
  font-size: 21px;
  letter-spacing: 0.5px;
  font-weight: 700;
}
.brand-text p { font-size: 12.5px; color: var(--text-dim); }

.search-wrap {
  position: relative;
  flex: 1;
  min-width: 280px;
  max-width: 520px;
}
.search-icon {
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-faint);
}
#search {
  width: 100%;
  font-family: var(--sans);
  font-size: 14px;
  color: var(--text);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 12px 18px 12px 42px;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}
#search::placeholder { color: var(--text-faint); }
#search:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

/* ---------- Filters ---------- */
.filters {
  position: sticky;
  top: 73px;
  z-index: 15;
  background: rgba(10, 14, 22, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-soft);
  padding: 12px 0;
}
.tabs { display: flex; gap: 10px; flex-wrap: wrap; }

.tab {
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--text-dim);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 8px 16px;
  cursor: pointer;
  transition: all 0.18s ease;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.tab:hover { color: var(--text); border-color: var(--text-faint); }
.tab .dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--tab-color, var(--accent));
}
.tab .count {
  font-size: 11px;
  color: var(--text-faint);
  background: var(--bg);
  border-radius: 999px;
  padding: 1px 7px;
}
.tab.active {
  color: var(--bg);
  background: var(--tab-color, var(--accent));
  border-color: var(--tab-color, var(--accent));
}
.tab.active .count { background: rgba(0,0,0,0.25); color: rgba(0,0,0,0.7); }
.tab.active .dot { background: rgba(0,0,0,0.4); }

/* ---------- Meta bar ---------- */
.meta-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
  margin: 28px 0 18px;
}
.result-count { font-size: 13px; color: var(--text-dim); font-family: var(--mono); }
.result-count b { color: var(--accent); }
.legend { font-size: 12px; color: var(--text-faint); }
.legend .d1 { color: var(--d1); }
.legend .d2 { color: var(--d2); }
.legend .d3 { color: var(--d3); }

/* ---------- Grid & Cards ---------- */
.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(330px, 1fr));
  gap: 20px;
  padding-bottom: 60px;
}

.card {
  position: relative;
  background: linear-gradient(180deg, var(--surface), var(--bg-soft));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  outline: none;
  transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
  overflow: hidden;
}
.card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: var(--card-accent, var(--accent));
  opacity: 0.85;
}
.card:hover, .card:focus-visible {
  transform: translateY(-4px);
  border-color: var(--card-accent, var(--accent));
  box-shadow: 0 12px 36px rgba(0,0,0,0.45), 0 0 0 1px var(--card-accent, var(--accent));
}

.card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}
.tool-name {
  font-family: var(--mono);
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
  word-break: break-word;
}
.cat-badge {
  flex-shrink: 0;
  font-family: var(--mono);
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  padding: 4px 10px;
  border-radius: 999px;
  color: var(--card-accent, var(--accent));
  background: color-mix(in srgb, var(--card-accent, var(--accent)) 14%, transparent);
  border: 1px solid color-mix(in srgb, var(--card-accent, var(--accent)) 35%, transparent);
}

.difficulty { display: flex; gap: 5px; align-items: center; }
.difficulty .pip {
  width: 22px; height: 5px; border-radius: 3px;
  background: var(--border);
}
.difficulty .pip.on { background: var(--diff-color, var(--accent)); }
.difficulty .label {
  font-size: 11px; color: var(--text-faint);
  font-family: var(--mono); margin-left: 4px;
}

.tagline { font-size: 14px; color: var(--text); font-weight: 500; }

.section-label {
  display: inline-block;
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--text-faint);
  margin-bottom: 4px;
}
.when-text { font-size: 13px; color: var(--text-dim); }

.use-cases { list-style: none; display: flex; flex-wrap: wrap; gap: 6px; }
.use-cases li {
  font-size: 11.5px;
  color: var(--text-dim);
  background: var(--surface-2);
  border: 1px solid var(--border-soft);
  border-radius: var(--radius-sm);
  padding: 3px 9px;
}

.command-block {
  position: relative;
  background: #070a11;
  border: 1px solid var(--border-soft);
  border-radius: var(--radius-sm);
  padding: 12px 40px 12px 14px;
}
.cmd-label {
  position: absolute; top: -8px; left: 12px;
  font-family: var(--mono); font-size: 9.5px; letter-spacing: 1px;
  color: var(--text-faint); background: var(--bg-soft);
  padding: 0 6px; text-transform: uppercase;
}
.command {
  font-family: var(--mono);
  font-size: 12.5px;
  color: #9be8c4;
  white-space: pre-wrap;
  word-break: break-all;
  display: block;
}
.copy-btn {
  position: absolute; top: 8px; right: 8px;
  background: var(--surface-2); border: 1px solid var(--border);
  color: var(--text-dim); border-radius: 6px;
  width: 28px; height: 28px; cursor: pointer; font-size: 14px;
  transition: all 0.15s;
}
.copy-btn:hover { color: var(--accent); border-color: var(--accent); }
.copy-btn.copied { color: var(--d1); border-color: var(--d1); }

.ai-btn {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 500;
  color: var(--accent);
  background: transparent;
  border: 1px dashed color-mix(in srgb, var(--accent) 50%, transparent);
  border-radius: var(--radius-sm);
  padding: 10px;
  cursor: pointer;
  transition: all 0.18s;
  display: flex; align-items: center; justify-content: center; gap: 8px;
}
.ai-btn:hover:not(:disabled) {
  background: var(--accent-glow);
  border-style: solid;
}
.ai-btn:disabled { opacity: 0.6; cursor: progress; }
.ai-icon { animation: spin-pulse 3s ease-in-out infinite; }
@keyframes spin-pulse { 50% { transform: scale(1.25) rotate(180deg); } }

.ai-output {
  font-size: 13px;
  color: var(--text);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
  line-height: 1.8;
  white-space: pre-wrap;
}
.ai-output.error { border-left-color: var(--d3); color: #ffb4bd; }
.ai-output .ai-tag {
  display: block;
  font-family: var(--mono); font-size: 10px; letter-spacing: 1px;
  color: var(--text-faint); text-transform: uppercase; margin-bottom: 6px;
}
.typing::after {
  content: "▋"; color: var(--accent);
  animation: blink 1s steps(1) infinite;
}

.sources { display: flex; flex-wrap: wrap; gap: 8px; margin-top: auto; padding-top: 6px; }
.source-link {
  font-family: var(--mono);
  font-size: 11.5px;
  color: var(--text-dim);
  text-decoration: none;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 4px 11px;
  display: inline-flex; align-items: center; gap: 5px;
  transition: all 0.15s;
}
.source-link:hover { color: var(--accent); border-color: var(--accent); }
.source-link::before { content: "↗"; font-size: 11px; }

/* ---------- Empty & Footer ---------- */
.empty-state {
  text-align: center;
  padding: 80px 20px;
  color: var(--text-dim);
}
.ghost-btn {
  margin-top: 16px;
  font-family: var(--mono); font-size: 13px;
  color: var(--accent); background: transparent;
  border: 1px solid var(--accent); border-radius: 999px;
  padding: 8px 20px; cursor: pointer; transition: all 0.15s;
}
.ghost-btn:hover { background: var(--accent-glow); }

.site-footer {
  border-top: 1px solid var(--border);
  padding: 28px 0;
  margin-top: 40px;
}
.site-footer p { font-size: 12px; color: var(--text-faint); text-align: center; }

.skeleton {
  background: linear-gradient(90deg, var(--surface) 25%, var(--surface-2) 50%, var(--surface) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.4s infinite;
  border-radius: var(--radius);
  height: 360px;
}
@keyframes shimmer { to { background-position: -200% 0; } }

/* ---------- Responsive ---------- */
@media (max-width: 720px) {
  .header-inner { gap: 14px; }
  .brand-text p { display: none; }
  .search-wrap { max-width: none; order: 3; }
  .filters { top: 69px; }
  .tool-grid { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
  html { scroll-behavior: auto; }
}