@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+KR:wght@400;500;700&family=Noto+Sans+JP:wght@400;500;700&family=DM+Sans:wght@400;500;600;700&display=swap');

:root {
  --primary: #FF5722;
  --primary-light: #FF7043;
  --primary-dark: #E64A19;
  --primary-bg: #FFF3EF;
  --accent: #FF8A65;
  --bg: #F8F9FA;
  --card: #FFFFFF;
  --border: #E8EAED;
  --border-light: #F1F3F4;
  --text: #202124;
  --text-sub: #5F6368;
  --text-light: #9AA0A6;
  --nav-bg: #FFFFFF;
  --input-bg: #F8F9FA;
  --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.10);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);
  --radius: 12px;
  --radius-sm: 8px;
  --radius-lg: 16px;
  --transition: all 0.2s ease;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: 'DM Sans', 'Noto Sans KR', 'Noto Sans JP', sans-serif;
  background: var(--bg);
  color: var(--text);
  font-size: 15px;
  line-height: 1.6;
  min-height: 100vh;
}

/* ── HEADER ── */
header {
  background: var(--nav-bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow);
}
.header-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: var(--text);
  font-weight: 700;
  font-size: 18px;
  flex-shrink: 0;
}
.logo-icon {
  width: 32px;
  height: 32px;
  background: var(--primary);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 16px;
}
.logo-text span { color: var(--primary); }

.lang-selector {
  display: flex;
  align-items: center;
  gap: 4px;
  flex-shrink: 0;
}
.lang-btn {
  padding: 4px 8px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: transparent;
  cursor: pointer;
  font-size: 12px;
  font-weight: 500;
  color: var(--text-sub);
  transition: var(--transition);
  white-space: nowrap;
}
.lang-btn:hover { background: var(--primary-bg); color: var(--primary); border-color: var(--primary); }
.lang-btn.active { background: var(--primary); color: white; border-color: var(--primary); }

/* ── CATEGORY NAV ── */
.cat-nav {
  background: var(--card);
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
  scrollbar-width: none;
}
.cat-nav::-webkit-scrollbar { display: none; }
.cat-nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  gap: 0;
}
.cat-btn {
  padding: 12px 16px;
  border: none;
  background: transparent;
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-sub);
  border-bottom: 2px solid transparent;
  transition: var(--transition);
  white-space: nowrap;
  text-decoration: none;
  display: block;
}
.cat-btn:hover { color: var(--primary); }
.cat-btn.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
  font-weight: 600;
}

/* ── MAIN LAYOUT ── */
.main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 24px 20px;
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 24px;
  align-items: start;
}
@media (max-width: 768px) {
  .main { grid-template-columns: 1fr; }
  .sidebar { order: 2; }
}

/* ── PAGE HERO ── */
.page-hero {
  margin-bottom: 20px;
}
.page-hero h1 {
  font-size: 24px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 4px;
}
.page-hero p {
  font-size: 14px;
  color: var(--text-sub);
}

/* ── CONVERTER CARD ── */
.converter-card {
  background: var(--card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  overflow: hidden;
  border: 1px solid var(--border);
}

/* Pair selector */
.pair-selector {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-light);
  display: flex;
  align-items: center;
  gap: 12px;
}
.unit-select-wrap {
  flex: 1;
  position: relative;
}
.unit-select {
  width: 100%;
  padding: 10px 36px 10px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--input-bg);
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  appearance: none;
  cursor: pointer;
  transition: var(--transition);
}
.unit-select:focus {
  outline: none;
  border-color: var(--primary);
  background: white;
}
.select-arrow {
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--primary);
  pointer-events: none;
  font-size: 12px;
}
.swap-btn {
  width: 36px;
  height: 36px;
  border: 1px solid var(--border);
  border-radius: 50%;
  background: white;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  font-size: 16px;
  transition: var(--transition);
  flex-shrink: 0;
}
.swap-btn:hover {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
  transform: rotate(180deg);
}

/* Input area */
.input-area {
  padding: 20px;
  border-bottom: 1px solid var(--border-light);
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 12px;
}
.input-group { display: flex; flex-direction: column; gap: 6px; }
.input-label { font-size: 12px; color: var(--text-sub); font-weight: 500; text-transform: uppercase; letter-spacing: 0.5px; }
.value-input {
  width: 100%;
  padding: 12px 14px;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 20px;
  font-weight: 600;
  color: var(--text);
  background: var(--input-bg);
  transition: var(--transition);
}
.value-input:focus {
  outline: none;
  border-color: var(--primary);
  background: white;
}
.value-input.result-input {
  color: var(--primary);
  background: var(--primary-bg);
  border-color: transparent;
  cursor: default;
}
.equals-sign {
  font-size: 24px;
  font-weight: 300;
  color: var(--text-light);
  text-align: center;
  padding-top: 24px;
}
.input-unit-badge {
  font-size: 12px;
  color: var(--text-sub);
  font-weight: 500;
  text-align: right;
  padding-right: 2px;
}

/* Action buttons */
.action-bar {
  padding: 12px 20px;
  display: flex;
  gap: 8px;
  border-bottom: 1px solid var(--border-light);
}
.action-btn {
  padding: 7px 14px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: white;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  color: var(--text-sub);
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 5px;
}
.action-btn:hover { background: var(--primary-bg); color: var(--primary); border-color: var(--primary); }
.action-btn.copy-btn.success { background: #E8F5E9; color: #2E7D32; border-color: #2E7D32; }

/* All units table */
.all-units {
  padding: 20px;
}
.all-units-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}
.all-units-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-sub);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.search-input {
  padding: 6px 12px;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 13px;
  background: var(--input-bg);
  color: var(--text);
  width: 160px;
  transition: var(--transition);
}
.search-input:focus { outline: none; border-color: var(--primary); background: white; width: 200px; }

.units-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 6px;
}
@media (max-width: 600px) { .units-grid { grid-template-columns: repeat(2, 1fr); } }

.unit-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  border: 1px solid transparent;
}
.unit-item:hover { background: var(--primary-bg); border-color: var(--primary); }
.unit-item.active { background: var(--primary-bg); border-color: var(--primary); }
.unit-name { font-size: 13px; color: var(--text); line-height: 1.3; }
.unit-value { font-size: 13px; font-weight: 600; color: var(--primary); text-align: right; }
.unit-symbol { font-size: 11px; color: var(--text-light); }

/* ── AD SLOTS ── */
.ad-slot {
  background: var(--card);
  border: 1px dashed var(--border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-light);
  font-size: 12px;
  text-align: center;
}
.ad-slot-top { height: 90px; margin-bottom: 20px; }
.ad-slot-sidebar { min-height: 250px; margin-bottom: 20px; }
.ad-slot-bottom { height: 90px; margin-top: 20px; }

/* ── SIDEBAR ── */
.sidebar {}
.sidebar-card {
  background: var(--card);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  overflow: hidden;
  margin-bottom: 16px;
}
.sidebar-card-title {
  padding: 14px 16px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-sub);
  border-bottom: 1px solid var(--border-light);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.cat-list { padding: 8px; }
.cat-list-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 10px;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--text);
  font-size: 14px;
  font-weight: 500;
  transition: var(--transition);
  cursor: pointer;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
}
.cat-list-item:hover { background: var(--primary-bg); color: var(--primary); }
.cat-list-item.active { background: var(--primary-bg); color: var(--primary); font-weight: 600; }
.cat-icon { font-size: 16px; width: 20px; text-align: center; }

/* ── HOME GRID ── */
.home-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 16px;
  margin-bottom: 24px;
}
.home-card {
  background: var(--card);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  padding: 20px;
  text-decoration: none;
  color: var(--text);
  display: flex;
  flex-direction: column;
  gap: 8px;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow);
}
.home-card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
  transform: translateY(-2px);
}
.home-card-icon { font-size: 28px; }
.home-card-title { font-size: 15px; font-weight: 700; }
.home-card-sub { font-size: 12px; color: var(--text-sub); }

/* ── FOOTER ── */
footer {
  background: var(--card);
  border-top: 1px solid var(--border);
  padding: 24px 20px;
  margin-top: 40px;
}
.footer-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}
.footer-copy { font-size: 13px; color: var(--text-sub); }
.footer-links { display: flex; gap: 16px; }
.footer-links a { font-size: 13px; color: var(--text-sub); text-decoration: none; }
.footer-links a:hover { color: var(--primary); }

/* ── BREADCRUMB ── */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--text-sub);
  margin-bottom: 16px;
}
.breadcrumb a { color: var(--primary); text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb-sep { color: var(--text-light); }

/* ── UTILITY ── */
.hidden { display: none !important; }
@media (max-width: 480px) {
  .pair-selector { flex-wrap: wrap; }
  .input-area { grid-template-columns: 1fr; }
  .equals-sign { display: none; }
  .units-grid { grid-template-columns: 1fr 1fr; }
  .home-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ── FAQ ── */
.faq-section {
  margin-top: 28px;
  background: var(--card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  overflow: hidden;
  margin-bottom: 20px;
}
.faq-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-light);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.faq-item {
  border-bottom: 1px solid var(--border-light);
}
.faq-item:last-child { border-bottom: none; }
.faq-q {
  width: 100%;
  text-align: left;
  padding: 14px 20px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  background: none;
  border: none;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  transition: var(--transition);
  line-height: 1.4;
}
.faq-q:hover { background: var(--primary-bg); color: var(--primary); }
.faq-arrow { font-size: 12px; color: var(--primary); flex-shrink: 0; transition: var(--transition); }
.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.7;
}
.faq-a.open {
  max-height: 300px;
  padding: 0 20px 16px;
}

/* ── FAQ ── */
.faq-section {
  margin-top: 28px;
  background: var(--card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  overflow: hidden;
  margin-bottom: 20px;
}
.faq-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--text);
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-light);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.faq-item {
  border-bottom: 1px solid var(--border-light);
}
.faq-item:last-child { border-bottom: none; }
.faq-q {
  width: 100%;
  text-align: left;
  padding: 14px 20px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  background: none;
  border: none;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  transition: var(--transition);
  line-height: 1.4;
}
.faq-q:hover { background: var(--primary-bg); color: var(--primary); }
.faq-arrow { font-size: 12px; color: var(--primary); flex-shrink: 0; transition: var(--transition); }
.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.7;
}
.faq-a.open {
  max-height: 300px;
  padding: 0 20px 16px;
}