/* ============================================
   KnowNewTech Tools – Design System
   Fonts: DM Serif Display + Outfit
   Palette: Sky Blue + Orange Accent
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=DM+Serif+Display:ital@0;1&family=Outfit:wght@300;400;500;600;700;800&display=swap');

/* ─── CSS Variables ─── */
:root {
  --primary:       #0284C7;
  --primary-dark:  #0369A1;
  --primary-light: #E0F2FE;
  --accent:        #F97316;
  --accent-dark:   #EA580C;
  --accent-light:  #FFF7ED;
  --dark:          #0C1A2E;
  --mid:           #475569;
  --muted:         #94A3B8;
  --border:        #E2E8F0;
  --surface:       #F8FBFF;
  --white:         #FFFFFF;
  --success:       #10B981;
  --error:         #EF4444;
  --warning:       #F59E0B;

  --radius-sm:     6px;
  --radius:        12px;
  --radius-lg:     20px;
  --radius-xl:     28px;

  --shadow-sm:     0 1px 3px rgba(0,0,0,.07), 0 1px 2px rgba(0,0,0,.04);
  --shadow:        0 4px 16px rgba(0,0,0,.08), 0 1px 4px rgba(0,0,0,.05);
  --shadow-lg:     0 12px 40px rgba(0,0,0,.12), 0 4px 12px rgba(0,0,0,.06);
  --shadow-primary:0 8px 24px rgba(2,132,199,.28);

  --transition:    all .22s cubic-bezier(.4,0,.2,1);
  --font-display:  'DM Serif Display', Georgia, serif;
  --font-body:     'Outfit', system-ui, sans-serif;
}

/* ─── Reset & Base ─── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: var(--font-body);
  background: var(--white);
  color: var(--dark);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul { list-style: none; }
button { cursor: pointer; font-family: inherit; }
input, textarea, select { font-family: inherit; }

/* ─── Container ─── */
.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}
.container-sm { max-width: 900px; margin: 0 auto; padding: 0 24px; }

/* ─── NAV ─── */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  height: 64px;
}
.navbar .container {
  display: flex;
  align-items: center;
  gap: 32px;
  height: 100%;
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--dark);
  white-space: nowrap;
}
.nav-logo .logo-icon {
  width: 36px; height: 36px;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  color: white; font-size: 18px;
}
.nav-logo span b { color: var(--primary); }

.nav-search {
  flex: 1;
  max-width: 420px;
  position: relative;
}
.nav-search input {
  width: 100%;
  padding: 9px 16px 9px 42px;
  border: 1.5px solid var(--border);
  border-radius: 50px;
  background: var(--surface);
  font-size: .9rem;
  color: var(--dark);
  transition: var(--transition);
}
.nav-search input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-light);
}
.nav-search .search-icon {
  position: absolute;
  left: 14px; top: 50%;
  transform: translateY(-50%);
  color: var(--muted);
  font-size: 16px;
  pointer-events: none;
}
.nav-links {
  display: flex;
  gap: 4px;
  margin-left: auto;
}
.nav-links a {
  padding: 7px 14px;
  border-radius: 8px;
  font-size: .875rem;
  font-weight: 500;
  color: var(--mid);
  transition: var(--transition);
}
.nav-links a:hover { background: var(--surface); color: var(--dark); }
.nav-links a.active { color: var(--primary); font-weight: 600; }

.nav-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 22px;
  color: var(--dark);
  margin-left: auto;
}

/* ─── HERO ─── */
.hero {
  background: var(--dark);
  position: relative;
  overflow: hidden;
  padding: 80px 0 70px;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.04) 1px, transparent 1px);
  background-size: 48px 48px;
}
.hero::after {
  content: '';
  position: absolute;
  top: -200px; right: -100px;
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(2,132,199,.3) 0%, transparent 65%);
  pointer-events: none;
}
.hero .container { position: relative; z-index: 2; text-align: center; }

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255,255,255,.08);
  border: 1px solid rgba(255,255,255,.15);
  color: rgba(255,255,255,.8);
  padding: 6px 16px;
  border-radius: 50px;
  font-size: .8rem;
  font-weight: 500;
  margin-bottom: 24px;
  letter-spacing: .03em;
}
.hero-badge span { color: var(--accent); }

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 5vw, 3.8rem);
  color: var(--white);
  line-height: 1.1;
  margin-bottom: 18px;
}
.hero h1 em { font-style: italic; color: #7DD3FC; }

.hero p {
  font-size: 1.1rem;
  color: rgba(255,255,255,.65);
  max-width: 540px;
  margin: 0 auto 36px;
}

.hero-search {
  display: flex;
  max-width: 580px;
  margin: 0 auto 20px;
  background: white;
  border-radius: 50px;
  padding: 6px 6px 6px 22px;
  box-shadow: var(--shadow-lg);
  gap: 8px;
}
.hero-search input {
  flex: 1;
  border: none;
  outline: none;
  font-size: 1rem;
  color: var(--dark);
  background: transparent;
}
.hero-search input::placeholder { color: var(--muted); }
.hero-search button {
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 50px;
  padding: 10px 24px;
  font-size: .9rem;
  font-weight: 600;
  transition: var(--transition);
  white-space: nowrap;
}
.hero-search button:hover { background: var(--primary-dark); transform: translateX(1px); }

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 32px;
  margin-top: 40px;
}
.hero-stat { text-align: center; }
.hero-stat strong {
  display: block;
  font-size: 1.6rem;
  font-weight: 800;
  color: white;
}
.hero-stat span {
  font-size: .8rem;
  color: rgba(255,255,255,.5);
  text-transform: uppercase;
  letter-spacing: .08em;
}

/* ─── SEARCH RESULTS DROPDOWN ─── */
.search-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  left: 0; right: 0;
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  z-index: 200;
  overflow: hidden;
  display: none;
}
.search-dropdown.open { display: block; }
.search-result-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  cursor: pointer;
  transition: var(--transition);
  border-bottom: 1px solid var(--border);
}
.search-result-item:last-child { border-bottom: none; }
.search-result-item:hover { background: var(--surface); }
.search-result-item .icon {
  width: 36px; height: 36px;
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 18px;
  flex-shrink: 0;
}
.search-result-item .info strong { display: block; font-size: .9rem; font-weight: 600; }
.search-result-item .info span { font-size: .78rem; color: var(--muted); }

/* ─── SECTION HEADERS ─── */
.section { padding: 72px 0; }
.section-sm { padding: 48px 0; }

.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  margin-bottom: 36px;
  gap: 16px;
}
.section-header h2 {
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  line-height: 1.2;
}
.section-header h2 span { color: var(--primary); }
.section-header p { color: var(--mid); margin-top: 6px; font-size: .95rem; }
.section-header a {
  color: var(--primary);
  font-size: .875rem;
  font-weight: 600;
  white-space: nowrap;
  display: flex; align-items: center; gap: 4px;
}
.section-header a:hover { color: var(--primary-dark); }

/* ─── CATEGORY CHIPS ─── */
.category-chips {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}
.chip {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 9px 18px;
  border-radius: 50px;
  border: 1.5px solid var(--border);
  background: white;
  font-size: .875rem;
  font-weight: 500;
  color: var(--mid);
  cursor: pointer;
  transition: var(--transition);
  user-select: none;
}
.chip .chip-icon { font-size: 16px; }
.chip:hover { border-color: var(--primary); color: var(--primary); background: var(--primary-light); }
.chip.active {
  background: var(--primary);
  border-color: var(--primary);
  color: white;
  box-shadow: var(--shadow-primary);
}

/* ─── CATEGORY HERO CARDS ─── */
.categories-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
}
.category-card {
  display: block;
  padding: 28px 24px;
  border-radius: var(--radius-lg);
  border: 1.5px solid transparent;
  background: var(--surface);
  cursor: pointer;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}
.category-card::before {
  content: '';
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity .22s;
}
.category-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
  border-color: var(--border);
}
.category-card:hover::before { opacity: 1; }

.cat-icon {
  width: 52px; height: 52px;
  border-radius: 14px;
  display: flex; align-items: center; justify-content: center;
  font-size: 24px;
  margin-bottom: 16px;
}
.category-card h3 { font-size: 1.05rem; font-weight: 700; margin-bottom: 6px; }
.category-card p { font-size: .82rem; color: var(--mid); line-height: 1.5; }
.category-card .tool-count {
  display: inline-block;
  margin-top: 14px;
  font-size: .78rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 50px;
}

/* Category colors */
.cat-finance  { --cat: #0284C7; --cat-bg: #E0F2FE; }
.cat-student  { --cat: #8B5CF6; --cat-bg: #EDE9FE; }
.cat-developer{ --cat: #0D9488; --cat-bg: #CCFBF1; }
.cat-text     { --cat: #DB2777; --cat-bg: #FCE7F3; }
.cat-converter{ --cat: #D97706; --cat-bg: #FEF3C7; }
.cat-math     { --cat: #059669; --cat-bg: #D1FAE5; }
.cat-health   { --cat: #DC2626; --cat-bg: #FEE2E2; }
.cat-utility  { --cat: #7C3AED; --cat-bg: #EDE9FE; }

.category-card .cat-icon {
  background: var(--cat-bg);
  color: var(--cat);
}
.category-card .tool-count {
  background: var(--cat-bg);
  color: var(--cat);
}
.category-card:hover { border-color: var(--cat); }

/* ─── TOOL CARDS GRID ─── */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(270px, 1fr));
  gap: 16px;
}
.tool-card {
  background: white;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 20px;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  gap: 10px;
  position: relative;
  overflow: hidden;
}
.tool-card::after {
  content: '';
  position: absolute;
  bottom: 0; left: 0;
  height: 3px; width: 0;
  background: var(--primary);
  transition: width .25s ease;
}
.tool-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
  border-color: var(--primary);
}
.tool-card:hover::after { width: 100%; }

.tool-card-icon {
  width: 44px; height: 44px;
  border-radius: 12px;
  background: var(--primary-light);
  display: flex; align-items: center; justify-content: center;
  font-size: 22px;
}
.tool-card h3 { font-size: .95rem; font-weight: 700; color: var(--dark); }
.tool-card p  { font-size: .8rem; color: var(--mid); line-height: 1.5; flex: 1; }
.tool-card .cat-badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: .72rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 50px;
  margin-top: auto;
  width: fit-content;
}
.tool-card .try-btn {
  display: flex;
  align-items: center;
  gap: 5px;
  color: var(--primary);
  font-size: .82rem;
  font-weight: 600;
  margin-top: 4px;
}

/* ─── TOOL PAGE ─── */
.tool-layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 28px;
  align-items: start;
}
.tool-main {
  background: white;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.tool-header {
  background: linear-gradient(135deg, var(--dark) 0%, #1E3A5F 100%);
  padding: 32px;
  display: flex;
  gap: 20px;
  align-items: flex-start;
}
.tool-header-icon {
  width: 60px; height: 60px;
  border-radius: 16px;
  background: rgba(255,255,255,.12);
  border: 1px solid rgba(255,255,255,.2);
  display: flex; align-items: center; justify-content: center;
  font-size: 28px;
  flex-shrink: 0;
}
.tool-header h1 {
  font-family: var(--font-display);
  font-size: 1.7rem;
  color: white;
  line-height: 1.2;
  margin-bottom: 6px;
}
.tool-header p { font-size: .9rem; color: rgba(255,255,255,.65); }
.tool-header .badge {
  display: inline-block;
  background: rgba(255,255,255,.15);
  color: rgba(255,255,255,.9);
  font-size: .72rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 50px;
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: .06em;
}

.tool-body { padding: 32px; }

/* ─── FORM ELEMENTS ─── */
.form-group { margin-bottom: 20px; }
.form-group label {
  display: block;
  font-size: .85rem;
  font-weight: 600;
  color: var(--dark);
  margin-bottom: 7px;
}
.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 11px 16px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  font-size: .95rem;
  color: var(--dark);
  background: white;
  transition: var(--transition);
  line-height: 1.5;
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-light);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: 50px;
  border: none;
  font-size: .9rem;
  font-weight: 600;
  transition: var(--transition);
  cursor: pointer;
}
.btn-primary {
  background: var(--primary);
  color: white;
  box-shadow: var(--shadow-primary);
}
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-1px); box-shadow: 0 12px 28px rgba(2,132,199,.35); }
.btn-outline {
  background: white;
  color: var(--primary);
  border: 1.5px solid var(--primary);
}
.btn-outline:hover { background: var(--primary-light); }
.btn-accent { background: var(--accent); color: white; }
.btn-accent:hover { background: var(--accent-dark); transform: translateY(-1px); }
.btn-danger { background: var(--error); color: white; }
.btn-sm { padding: 8px 18px; font-size: .82rem; }
.btn-full { width: 100%; }
.btn-group { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 8px; }

/* ─── RESULT BOX ─── */
.result-box {
  margin-top: 24px;
  background: linear-gradient(135deg, var(--dark) 0%, #1E3A5F 100%);
  border-radius: var(--radius);
  padding: 24px 28px;
  display: none;
}
.result-box.show { display: block; animation: slideUp .3s ease; }
.result-label { font-size: .75rem; font-weight: 600; color: rgba(255,255,255,.5); text-transform: uppercase; letter-spacing: .08em; margin-bottom: 6px; }
.result-value { font-size: 2.4rem; font-weight: 800; color: white; line-height: 1; }
.result-value span { font-size: 1rem; font-weight: 500; color: rgba(255,255,255,.6); }
.result-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 16px; }
.result-item { text-align: center; }
.result-item .r-label { font-size: .72rem; color: rgba(255,255,255,.5); margin-bottom: 4px; }
.result-item .r-val { font-size: 1.3rem; font-weight: 700; color: white; }

/* Textarea result */
.result-textarea {
  width: 100%;
  min-height: 160px;
  padding: 14px 16px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  font-size: .9rem;
  resize: vertical;
  background: var(--surface);
  color: var(--dark);
  font-family: 'Courier New', monospace;
  line-height: 1.6;
}

/* ─── BREADCRUMB ─── */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: .82rem;
  color: var(--muted);
  padding: 20px 0 0;
}
.breadcrumb a { color: var(--primary); font-weight: 500; }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb .sep { color: var(--border); }

/* ─── SIDEBAR ─── */
.tool-sidebar { display: flex; flex-direction: column; gap: 20px; }

.sidebar-card {
  background: white;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
}
.sidebar-card h4 {
  font-size: .9rem;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--dark);
}
.related-tool-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px;
  border-radius: 8px;
  cursor: pointer;
  transition: var(--transition);
  font-size: .85rem;
  font-weight: 500;
  color: var(--dark);
}
.related-tool-link:hover { background: var(--surface); color: var(--primary); }
.related-tool-link .icon {
  width: 32px; height: 32px;
  border-radius: 8px;
  background: var(--primary-light);
  display: flex; align-items: center; justify-content: center;
  font-size: 16px;
  flex-shrink: 0;
}

/* ─── AD SLOTS ─── */
.ad-slot {
  background: var(--surface);
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  font-size: .8rem;
  text-align: center;
  padding: 12px;
  letter-spacing: .03em;
}
.ad-slot-728 { height: 90px; }
.ad-slot-300 { height: 250px; }
.ad-slot-320 { height: 100px; }

/* ─── CATEGORY PAGE HERO ─── */
.cat-page-hero {
  background: var(--dark);
  padding: 52px 0;
  position: relative;
  overflow: hidden;
}
.cat-page-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.03) 1px, transparent 1px);
  background-size: 40px 40px;
}
.cat-page-hero .container { position: relative; z-index: 2; }
.cat-hero-icon {
  width: 64px; height: 64px;
  border-radius: 18px;
  display: flex; align-items: center; justify-content: center;
  font-size: 30px;
  margin-bottom: 16px;
}
.cat-page-hero h1 {
  font-family: var(--font-display);
  font-size: 2.2rem;
  color: white;
  margin-bottom: 10px;
}
.cat-page-hero p { color: rgba(255,255,255,.65); max-width: 500px; }

/* ─── FILTER BAR ─── */
.filter-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 20px 0;
  flex-wrap: wrap;
}
.filter-bar label { font-size: .85rem; font-weight: 600; color: var(--mid); }
.filter-search {
  flex: 1; min-width: 200px; max-width: 320px;
  padding: 9px 14px;
  border: 1.5px solid var(--border);
  border-radius: 50px;
  font-size: .875rem;
  background: white;
}
.filter-search:focus { outline: none; border-color: var(--primary); }

/* ─── INFO CARDS ─── */
.info-strip {
  background: var(--primary-light);
  border-radius: var(--radius);
  padding: 18px 22px;
  display: flex;
  gap: 12px;
  align-items: flex-start;
  margin-bottom: 24px;
}
.info-strip .icon { font-size: 20px; flex-shrink: 0; margin-top: 2px; }
.info-strip p { font-size: .875rem; color: var(--primary-dark); line-height: 1.6; }

/* ─── SCIENTIFIC CALC ─── */
.sci-calc {
  background: var(--dark);
  border-radius: var(--radius);
  padding: 20px;
  max-width: 360px;
}
.sci-display {
  background: rgba(255,255,255,.06);
  border-radius: 10px;
  padding: 16px 20px;
  margin-bottom: 16px;
  text-align: right;
}
.sci-display .expr { font-size: .85rem; color: rgba(255,255,255,.4); min-height: 20px; }
.sci-display .val { font-size: 2.2rem; font-weight: 700; color: white; font-family: 'Courier New', monospace; }
.sci-keys { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; }
.sci-key {
  padding: 12px 6px;
  border: none;
  border-radius: 8px;
  font-size: .82rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  background: rgba(255,255,255,.08);
  color: rgba(255,255,255,.85);
}
.sci-key:hover { background: rgba(255,255,255,.16); transform: scale(1.04); }
.sci-key.op { background: rgba(2,132,199,.25); color: #7DD3FC; }
.sci-key.eq { background: var(--primary); color: white; grid-column: span 2; }
.sci-key.fn { background: rgba(249,115,22,.2); color: #FDBA74; font-size: .75rem; }
.sci-key.zero { grid-column: span 2; }

/* ─── STOPWATCH / TIMER ─── */
.timer-display {
  text-align: center;
  padding: 32px;
  background: var(--dark);
  border-radius: var(--radius);
  margin-bottom: 20px;
}
.timer-time {
  font-size: 4rem;
  font-weight: 800;
  color: white;
  font-family: 'Courier New', monospace;
  letter-spacing: -.02em;
}
.timer-ms { font-size: 2rem; color: rgba(255,255,255,.4); }

/* ─── FOOTER ─── */
footer {
  background: var(--dark);
  color: rgba(255,255,255,.7);
  padding: 60px 0 0;
  margin-top: 80px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 48px;
}
.footer-brand .logo { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.footer-brand .logo-icon {
  width: 36px; height: 36px;
  background: linear-gradient(135deg, var(--primary), #0EA5E9);
  border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  font-size: 18px;
}
.footer-brand .logo strong { color: white; font-size: 1.1rem; }
.footer-brand p { font-size: .875rem; line-height: 1.7; max-width: 260px; }

.footer-col h5 { color: white; font-size: .9rem; font-weight: 700; margin-bottom: 14px; }
.footer-col ul { display: flex; flex-direction: column; gap: 8px; }
.footer-col ul a {
  font-size: .83rem;
  color: rgba(255,255,255,.55);
  transition: color .18s;
}
.footer-col ul a:hover { color: white; }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.08);
  padding: 20px 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: .8rem;
  color: rgba(255,255,255,.35);
  gap: 16px;
  flex-wrap: wrap;
}
.footer-bottom a { color: rgba(255,255,255,.5); }
.footer-bottom a:hover { color: white; }

/* ─── MOBILE MENU ─── */
.mobile-nav {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 999;
  background: white;
  padding: 24px;
  flex-direction: column;
  gap: 12px;
}
.mobile-nav.open { display: flex; }
.mobile-nav-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; }
.mobile-nav a {
  display: block;
  padding: 13px 16px;
  border-radius: var(--radius);
  font-size: 1rem;
  font-weight: 500;
  color: var(--dark);
  background: var(--surface);
  transition: var(--transition);
}
.mobile-nav a:hover { background: var(--primary-light); color: var(--primary); }

/* ─── ANIMATIONS ─── */
@keyframes slideUp {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to   { opacity: 1; }
}
.animate-up { animation: slideUp .35s ease both; }
.animate-fade { animation: fadeIn .3s ease both; }

/* Stagger cards */
.tools-grid .tool-card:nth-child(1)  { animation-delay: .05s; }
.tools-grid .tool-card:nth-child(2)  { animation-delay: .1s;  }
.tools-grid .tool-card:nth-child(3)  { animation-delay: .15s; }
.tools-grid .tool-card:nth-child(4)  { animation-delay: .2s;  }
.tools-grid .tool-card:nth-child(5)  { animation-delay: .25s; }
.tools-grid .tool-card:nth-child(6)  { animation-delay: .3s;  }

/* ─── UTILITY ─── */
.text-center { text-align: center; }
.text-muted   { color: var(--muted); }
.mt-4  { margin-top: 16px; }
.mt-6  { margin-top: 24px; }
.mt-8  { margin-top: 32px; }
.mb-4  { margin-bottom: 16px; }
.mb-6  { margin-bottom: 24px; }
.divider { height: 1px; background: var(--border); margin: 24px 0; }
.tag-list { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.tag { padding: 4px 12px; border-radius: 50px; background: var(--surface); border: 1px solid var(--border); font-size: .78rem; color: var(--mid); }

/* empty state */
.empty-state { text-align: center; padding: 60px 24px; }
.empty-state .icon { font-size: 48px; margin-bottom: 16px; }
.empty-state h3 { font-size: 1.2rem; margin-bottom: 8px; }
.empty-state p  { color: var(--mid); }

/* ─── RESPONSIVE ─── */
@media (max-width: 1024px) {
  .tool-layout { grid-template-columns: 1fr; }
  .tool-sidebar { display: grid; grid-template-columns: 1fr 1fr; }
  .footer-grid  { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .nav-links, .nav-search { display: none; }
  .nav-menu-btn { display: block; }
  .hero { padding: 60px 0 50px; }
  .hero-stats { gap: 20px; flex-wrap: wrap; }
  .form-row { grid-template-columns: 1fr; }
  .tool-sidebar { grid-template-columns: 1fr; }
  .footer-grid  { grid-template-columns: 1fr; gap: 28px; }
  .section { padding: 48px 0; }
  .section-header { flex-direction: column; align-items: flex-start; }
  .sci-keys { grid-template-columns: repeat(4,1fr); }
  .timer-time { font-size: 3rem; }
  .categories-grid { grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); }
}
@media (max-width: 480px) {
  .container { padding: 0 16px; }
  .hero-search { padding: 5px 5px 5px 16px; }
  .hero-search button { padding: 10px 16px; font-size: .82rem; }
  .tools-grid { grid-template-columns: 1fr; }
  .result-grid { grid-template-columns: 1fr 1fr; }
}

/* ─── PRINT ─── */
@media print {
  .navbar, footer, .ad-slot, .tool-sidebar { display: none; }
  .tool-layout { grid-template-columns: 1fr; }
}