:root {
  color-scheme: light;
  --bg: #f5f7f8;
  --panel: #ffffff;
  --panel-soft: #eef3f1;
  --ink: #1d2528;
  --muted: #667176;
  --line: #dbe3e0;
  --accent: #0f766e;
  --accent-dark: #115e59;
  --accent-soft: #d8f1ed;
  --warn: #b45309;
  --shadow: 0 16px 40px rgba(31, 41, 55, 0.08);
  --field-bg: #ffffff;
  --sidebar-bg: #fbfcfc;
}

[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0f1417;
  --panel: #171d21;
  --panel-soft: #1f272b;
  --ink: #e8edef;
  --muted: #9aa6ab;
  --line: #2a353a;
  --accent: #2dd4bf;
  --accent-dark: #99f6e4;
  --accent-soft: #123733;
  --warn: #fbbf24;
  --shadow: 0 16px 40px rgba(0, 0, 0, 0.45);
  --field-bg: #10161a;
  --sidebar-bg: #12181b;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--ink);
  font-family: Inter, "Segoe UI", "Apple SD Gothic Neo", "Noto Sans KR", Arial, sans-serif;
}

button,
input,
select {
  font: inherit;
}

button {
  cursor: pointer;
}

.app-shell {
  display: grid;
  grid-template-columns: 320px minmax(0, 1fr);
  min-height: 100vh;
}

.sidebar {
  display: flex;
  flex-direction: column;
  gap: 22px;
  padding: 28px 22px;
  border-right: 1px solid var(--line);
  background: var(--sidebar-bg);
}

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

.brand-mark {
  display: grid;
  place-items: center;
  width: 56px;
  height: 56px;
  border-radius: 8px;
  background: var(--accent);
  color: #ffffff;
  font-weight: 800;
}

.brand h1,
.brand p,
.topbar h2,
.topbar p,
.side-section h2,
.result-panel p {
  margin: 0;
}

.brand h1 {
  font-size: 25px;
  line-height: 1;
}

.brand p,
.eyebrow,
.result-label,
.result-detail,
.helper {
  color: var(--muted);
}

.search {
  display: grid;
  gap: 8px;
  font-size: 13px;
  font-weight: 700;
  color: var(--muted);
}

.search input,
.field input,
.field select {
  width: 100%;
  min-height: 44px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--field-bg);
  color: var(--ink);
  padding: 10px 12px;
  outline: none;
}

.search input:focus,
.field input:focus,
.field select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.sidebar-banner {
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.sidebar-banner img {
  display: block;
  width: 100%;
  height: auto;
}

.category-tabs {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.category-tabs button,
.category-tabs a.category-tab-link,
.tool-chip,
.mini-list button,
.action-button,
.keypad button,
.icon-button {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  color: var(--ink);
}

.category-tabs button,
.category-tabs a.category-tab-link {
  min-height: 40px;
  font-weight: 700;
}

.category-tabs a.category-tab-link {
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  color: var(--ink);
}

.category-tabs button.active,
.tool-chip.active {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent-dark);
}

.side-section {
  display: grid;
  gap: 10px;
}

.side-section h2 {
  font-size: 13px;
  color: var(--muted);
}

.mini-list {
  display: grid;
  gap: 8px;
}

.mini-list.empty {
  min-height: 38px;
  align-content: center;
  color: var(--muted);
  font-size: 14px;
}

.mini-list button {
  min-height: 38px;
  text-align: left;
  padding: 8px 10px;
}

.workspace {
  min-width: 0;
  padding: 28px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 20px;
}

.eyebrow {
  font-size: 13px;
  font-weight: 800;
  text-transform: uppercase;
}

.topbar h2 {
  margin-top: 4px;
  font-size: 32px;
}

.topbar-actions {
  display: flex;
  gap: 10px;
}

.icon-button {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  font-size: 22px;
}

.icon-button.active {
  border-color: var(--warn);
  background: #fff7ed;
  color: var(--warn);
}

.tool-strip {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 12px;
  margin-bottom: 10px;
}

.tool-chip {
  flex: 0 0 auto;
  min-height: 38px;
  padding: 8px 12px;
  font-weight: 700;
}

.calculator-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 340px;
  gap: 18px;
  align-items: start;
}

.tool-panel,
.result-panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.tool-panel {
  padding: 22px;
}

.result-panel {
  position: sticky;
  top: 24px;
  display: grid;
  gap: 8px;
  padding: 22px;
}

.result-label {
  font-size: 13px;
  font-weight: 800;
}

.result-value {
  overflow-wrap: anywhere;
  font-size: 34px;
  font-weight: 850;
}

.result-detail {
  line-height: 1.5;
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.field {
  display: grid;
  gap: 7px;
}

.field.full {
  grid-column: 1 / -1;
}

.field label {
  font-size: 13px;
  font-weight: 800;
  color: var(--muted);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 16px;
}

.action-button {
  min-height: 42px;
  padding: 9px 14px;
  font-weight: 800;
}

.action-button.primary {
  border-color: var(--accent);
  background: var(--accent);
  color: white;
}

.display {
  display: grid;
  gap: 10px;
}

.display input {
  width: 100%;
  min-height: 72px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--field-bg);
  color: var(--ink);
  padding: 12px;
  text-align: right;
  font-size: 30px;
  font-weight: 800;
}

.keypad {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  margin-top: 16px;
}

.keypad button {
  min-height: 56px;
  font-size: 20px;
  font-weight: 800;
}

.keypad .operator {
  background: var(--panel-soft);
}

.keypad .equals {
  border-color: var(--accent);
  background: var(--accent);
  color: white;
}

.helper {
  margin: 12px 0 0;
  line-height: 1.5;
}

.qr-box {
  display: flex;
  justify-content: center;
  margin-top: 16px;
}

.qr-box img {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
  padding: 8px;
}

@media (max-width: 980px) {
  .app-shell {
    grid-template-columns: 1fr;
  }

  .sidebar {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .calculator-layout {
    grid-template-columns: 1fr;
  }

  .result-panel {
    position: static;
  }
}

@media (max-width: 640px) {
  .workspace,
  .sidebar {
    padding: 20px 16px;
  }

  .topbar h2 {
    font-size: 25px;
  }

  .form-grid {
    grid-template-columns: 1fr;
  }

  .result-value {
    font-size: 28px;
  }
}

.site-footer {
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  display: grid;
  gap: 10px;
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
}

.site-footer a {
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
  font-weight: 700;
}

.site-footer a:hover,
.site-footer a[aria-current="page"] {
  color: var(--accent-dark);
}

.site-footer p {
  margin: 0;
  color: var(--muted);
  font-size: 13px;
}

.ad-slot {
  display: none;
  min-height: 90px;
  margin-top: 18px;
  border: 1px dashed var(--line);
  border-radius: 8px;
  background: var(--panel-soft);
}

.ad-slot[data-ads-ready="true"] {
  display: block;
}

.page-shell {
  max-width: 760px;
  margin: 0 auto;
  min-height: 100vh;
  padding: 24px 20px 32px;
}

.page-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 28px;
}

.page-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--ink);
  text-decoration: none;
  font-size: 22px;
  font-weight: 800;
}

.page-brand .brand-mark {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border-radius: 8px;
  background: var(--accent);
  color: #ffffff;
  font-size: 14px;
  font-weight: 800;
}

.page-content {
  display: grid;
  gap: 24px;
}

.page-content h1 {
  margin: 0;
  font-size: 34px;
}

.page-lead,
.page-meta {
  margin: -8px 0 0;
  color: var(--muted);
  line-height: 1.6;
}

.page-content section {
  display: grid;
  gap: 10px;
}

.page-content h2 {
  margin: 0;
  font-size: 20px;
}

.page-content p,
.page-content li,
.page-content dd {
  margin: 0;
  line-height: 1.7;
  color: var(--ink);
}

.page-content ul,
.page-content dl {
  margin: 0;
  padding-left: 20px;
}

.page-content code {
  padding: 2px 6px;
  border-radius: 4px;
  background: var(--panel-soft);
  font-size: 0.92em;
}

.page-content a {
  color: var(--accent-dark);
}

.blog-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.blog-list-item {
  display: grid;
  gap: 6px;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
}

.blog-list-item a {
  display: grid;
  gap: 4px;
  text-decoration: none;
  color: var(--ink);
}

.blog-list-title {
  font-size: 18px;
  font-weight: 800;
}

.blog-list-meta {
  font-size: 13px;
  color: var(--muted);
}

.blog-list-excerpt {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--muted);
}

.blog-post {
  display: grid;
  gap: 20px;
}

.blog-post-header h1 {
  margin: 0;
}

.blog-body {
  display: grid;
  gap: 14px;
  line-height: 1.75;
}

.blog-body h2 {
  margin: 8px 0 0;
  font-size: 20px;
}

.blog-body p,
.blog-body li {
  margin: 0;
}

.blog-body ul {
  margin: 0;
  padding-left: 20px;
}

.blog-body table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.blog-body th,
.blog-body td {
  border: 1px solid var(--line);
  padding: 8px 10px;
  text-align: left;
}

.blog-back {
  margin: 0;
  padding-top: 8px;
  border-top: 1px solid var(--line);
}

.preview-banner {
  margin: 0;
  padding: 12px 14px;
  border: 1px solid #f59e0b;
  border-radius: 8px;
  background: #fffbeb;
  color: #92400e;
  font-size: 14px;
  font-weight: 700;
  line-height: 1.5;
}

[data-theme="dark"] .preview-banner {
  border-color: #b45309;
  background: #422006;
  color: #fcd34d;
}

.faq-list {
  display: grid;
  gap: 16px;
}

.faq-list dt {
  font-weight: 800;
}

.faq-list dd {
  margin-top: 4px;
  color: var(--muted);
}