:root {
  color-scheme: light;
  --bg: #f5f7fb;
  --bg-soft: #ffffff;
  --surface: #ffffff;
  --surface-strong: #eef3f8;
  --text: #17202a;
  --muted: #5b6675;
  --border: #d8e0ea;
  --brand: #16697a;
  --brand-strong: #0d3f4a;
  --brand-soft: #e3f3f5;
  --accent: #9a5b13;
  --accent-soft: #fff1da;
  --danger: #b42318;
  --shadow: 0 18px 42px rgba(23, 32, 42, 0.1);
  --radius: 8px;
  --max: 1180px;
  --space-1: 8px;
  --space-2: 12px;
  --space-3: 16px;
  --space-4: 20px;
  --space-5: 24px;
}

[data-theme="dark"] {
  color-scheme: dark;
  --bg: #101418;
  --bg-soft: #161b22;
  --surface: #1b222b;
  --surface-strong: #222b35;
  --text: #f3f7fb;
  --muted: #b7c1cc;
  --border: #334150;
  --brand: #5fc9d8;
  --brand-strong: #b8eef5;
  --brand-soft: #183840;
  --accent: #f0b35a;
  --accent-soft: #3b2c18;
  --danger: #ff9d9d;
  --shadow: 0 18px 42px rgba(0, 0, 0, 0.28);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  background: linear-gradient(180deg, var(--bg-soft), var(--bg));
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
  line-height: 1.65;
  overflow-x: hidden;
}

a {
  color: inherit;
}

img,
svg {
  max-width: 100%;
}

button,
input,
textarea,
select {
  font: inherit;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--surface) 92%, transparent);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(14px);
}

.container {
  width: min(100% - 40px, var(--max));
  margin: 0 auto;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  gap: var(--space-3);
}

.brand {
  display: inline-flex;
  flex-direction: column;
  text-decoration: none;
  min-width: 0;
}

.brand-name {
  color: var(--brand-strong);
  font-size: clamp(1.05rem, 2vw, 1.45rem);
  font-weight: 800;
  line-height: 1.15;
}

.brand-note {
  color: var(--muted);
  font-size: 0.85rem;
  white-space: nowrap;
}

.nav-wrap {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.main-nav a {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  border-radius: var(--radius);
  padding: 0 var(--space-2);
  color: var(--muted);
  text-decoration: none;
  font-weight: 700;
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--brand-strong);
  background: var(--brand-soft);
}

.icon-btn,
.menu-toggle {
  min-width: 44px;
  height: 44px;
  display: inline-grid;
  place-items: center;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  padding: 0 var(--space-2);
  font-weight: 800;
}

.icon-btn:hover,
.menu-toggle:hover {
  border-color: var(--brand);
  color: var(--brand-strong);
}

.menu-toggle {
  display: none;
}

.hero {
  padding: 38px 0 var(--space-4);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
h4 {
  line-height: 1.2;
  color: var(--brand-strong);
}

h1 {
  margin: 0;
  max-width: 880px;
  font-size: clamp(2rem, 5vw, 3.9rem);
}

.hero-lead {
  max-width: 820px;
  margin: 14px 0 0;
  color: var(--muted);
  font-size: clamp(1rem, 2vw, 1.2rem);
}

.mini-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  margin-top: var(--space-4);
}

.mini-links a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0 14px;
  background: var(--surface);
  color: var(--muted);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 700;
}

.tool-shell,
.content-card,
.page-card {
  background: color-mix(in srgb, var(--surface) 96%, transparent);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.tool-shell {
  display: grid;
  gap: var(--space-4);
  margin: var(--space-4) auto 44px;
  padding: clamp(18px, 2.5vw, 28px);
}

.tool-header {
  display: flex;
  justify-content: space-between;
  gap: var(--space-3);
  align-items: flex-start;
  margin-bottom: 0;
}

.tool-header h2 {
  margin: 0 0 4px;
  font-size: clamp(1.4rem, 3vw, 2rem);
}

.tool-header p {
  margin: 0;
  color: var(--muted);
}

.badge {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  border-radius: 999px;
  padding: 0 var(--space-2);
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 800;
  white-space: nowrap;
}

.toolbar {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-3);
  margin-bottom: 0;
  align-items: end;
}

.options-bottom {
  border-top: 1px solid var(--border);
  padding-top: var(--space-4);
}

.toolbar > div {
  display: grid;
  min-width: 0;
  gap: var(--space-1);
}

.style-tabs,
.options-row,
.shortcut-row,
.action-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.options-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  align-items: end;
}

.options-row > .select-field {
  align-self: end;
}

.style-tab,
.shortcut-btn,
.action-btn,
.option-btn {
  min-height: 44px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  font-weight: 800;
  padding: 0 var(--space-3);
  text-align: center;
}

.style-tab[aria-pressed="true"],
.option-btn[aria-pressed="true"] {
  background: var(--brand);
  border-color: var(--brand);
  color: #fffaf0;
}

.style-tab:hover,
.shortcut-btn:hover,
.action-btn:hover,
.option-btn:hover {
  border-color: var(--brand);
}

.select-field {
  width: 100%;
  min-height: 44px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  padding: 0 var(--space-2);
  font-weight: 700;
}

.control-label,
.select-block {
  display: grid;
  gap: var(--space-1);
  color: var(--brand-strong);
  font-size: 0.92rem;
  font-weight: 800;
}

.select-block {
  min-width: 0;
}

.translator-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  gap: var(--space-3);
  align-items: stretch;
}

.panel {
  display: flex;
  min-width: 0;
  flex-direction: column;
  height: 100%;
}

.panel-head {
  display: flex;
  justify-content: space-between;
  gap: var(--space-2);
  align-items: center;
  margin-bottom: var(--space-1);
}

.panel-head label,
.panel-head span {
  font-size: 0.92rem;
  font-weight: 800;
}

.panel-head span {
  color: var(--muted);
  white-space: nowrap;
}

textarea {
  width: 100%;
  min-height: 300px;
  height: 100%;
  resize: vertical;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  padding: var(--space-3);
  outline: none;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.25);
}

textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 18%, transparent);
}

#outputText {
  background: var(--surface-strong);
}

.swap-column {
  display: flex;
  align-items: center;
  justify-content: center;
  padding-top: 32px;
}

.swap-btn {
  width: 48px;
  height: 48px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--brand);
  color: #fffaf0;
  cursor: pointer;
  font-size: 1.1rem;
  font-weight: 900;
}

.action-area {
  display: flex;
  justify-content: space-between;
  gap: var(--space-3);
  align-items: center;
  margin-top: 0;
}

.action-row {
  align-items: center;
}

.primary-btn {
  min-height: 48px;
  border: 1px solid var(--brand);
  border-radius: var(--radius);
  background: var(--brand);
  color: #fffaf0;
  cursor: pointer;
  font-weight: 900;
  padding: 0 var(--space-5);
}

.primary-btn:hover,
.swap-btn:hover {
  background: var(--brand-strong);
}

.status {
  min-height: 24px;
  color: var(--muted);
  font-size: 0.92rem;
  font-weight: 700;
  text-align: right;
}

.shortcuts {
  margin-top: 0;
  border-top: 1px solid var(--border);
  padding-top: var(--space-4);
}

.translator-links {
  margin-top: 0;
  border-top: 1px solid var(--border);
  padding-top: var(--space-4);
}

.shortcuts h3,
.translator-links h3,
.history-panel h3,
.grammar-box h3 {
  margin: 0 0 10px;
  font-size: 1.05rem;
}

.grammar-box {
  margin-top: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface-strong);
  padding: var(--space-3);
  line-height: 1.55;
}

.inline-faqs {
  display: grid;
  gap: var(--space-1);
  margin: 0 0 var(--space-4);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  padding: var(--space-3);
}

.inline-faqs h3 {
  margin: 0;
  color: var(--brand-strong);
  font-size: 1rem;
}

.inline-faqs details {
  border-top: 1px solid var(--border);
  padding-top: var(--space-1);
}

.inline-faqs summary {
  cursor: pointer;
  color: var(--text);
  font-weight: 800;
}

.inline-faqs p {
  margin: var(--space-1) 0 0;
  color: var(--muted);
}

.grammar-box p {
  margin: 0;
}

.grammar-box ul {
  margin: 0;
  padding-left: 1.2rem;
}

.warning-box {
  margin-top: 12px;
  border-left: 4px solid var(--danger);
  padding: 10px 12px;
  background: color-mix(in srgb, var(--danger) 10%, transparent);
}

.small-note {
  margin-top: 12px !important;
  color: var(--muted);
  font-size: 0.92rem;
}

.history-panel {
  display: none;
  margin-top: 0;
  border-top: 1px solid var(--border);
  padding-top: var(--space-4);
}

.history-panel.open {
  display: block;
}

.history-list {
  display: grid;
  gap: var(--space-2);
}

.history-item {
  display: grid;
  gap: var(--space-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  padding: var(--space-3);
}

.history-item p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.history-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.content-section {
  padding: 16px 0 58px;
}

.content-card {
  padding: clamp(18px, 4vw, 44px);
}

.content-card > h2 {
  margin-top: 0;
  font-size: clamp(1.7rem, 4vw, 2.6rem);
}

.seo-content {
  max-width: 920px;
}

.seo-content h2 {
  margin-top: 2.3rem;
  font-size: clamp(1.45rem, 3vw, 2rem);
}

.seo-content h3 {
  margin-top: 1.6rem;
  font-size: 1.25rem;
}

.seo-content p,
.seo-content li {
  color: var(--text);
}

.seo-content p {
  margin: 0 0 1rem;
}

.seo-content ul,
.seo-content ol {
  padding-left: 1.2rem;
}

.example-table {
  width: 100%;
  border-collapse: collapse;
  margin: 18px 0;
  overflow: hidden;
  border-radius: var(--radius);
}

.example-table th,
.example-table td {
  border: 1px solid var(--border);
  padding: 12px;
  vertical-align: top;
}

.example-table th {
  background: var(--brand-soft);
  color: var(--brand-strong);
  text-align: left;
}

.page-main {
  padding: 34px 0 64px;
}

.page-card {
  padding: clamp(20px, 4vw, 46px);
}

.page-card h1 {
  font-size: clamp(2rem, 5vw, 3.4rem);
}

.page-card p {
  max-width: 900px;
}

.contact-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 420px);
  gap: 22px;
  align-items: start;
}

.contact-form {
  display: grid;
  gap: 12px;
}

.contact-form label {
  display: grid;
  gap: 6px;
  font-weight: 800;
}

.contact-form input,
.contact-form textarea {
  min-height: 44px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  padding: 10px 12px;
}

.site-footer {
  border-top: 1px solid var(--border);
  background: var(--surface);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 24px 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.footer-inner nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-inner a {
  color: var(--muted);
  font-weight: 700;
  text-decoration: none;
}

.footer-inner a:hover {
  color: var(--brand-strong);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

@media (max-width: 767px) {
  .container {
    width: min(100% - 24px, var(--max));
  }

  .header-inner {
    min-height: 64px;
  }

  .brand-note {
    display: none;
  }

  .menu-toggle {
    display: inline-grid;
  }

  .main-nav {
    position: absolute;
    left: 12px;
    right: 12px;
    top: 68px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--surface);
    box-shadow: var(--shadow);
    padding: 8px;
  }

  .main-nav.open {
    display: flex;
  }

  .main-nav a {
    width: 100%;
  }

  .hero {
    padding: var(--space-5) 0 var(--space-3);
  }

  .mini-links {
    display: grid;
    grid-template-columns: 1fr;
  }

  .tool-header,
  .action-area,
  .footer-inner {
    flex-direction: column;
    align-items: stretch;
  }

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

  .style-tabs,
  .options-row,
  .shortcut-row,
  .action-row {
    display: grid;
    grid-template-columns: 1fr;
  }

  .style-tab,
  .shortcut-btn,
  .action-btn,
  .option-btn,
  .primary-btn,
  .select-field {
    width: 100%;
  }

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

  .swap-column {
    min-height: 48px;
    padding-top: 0;
  }

  .swap-btn {
    transform: rotate(90deg);
  }

  textarea {
    min-height: 220px;
    height: auto;
  }

  .panel-head {
    align-items: flex-start;
    flex-direction: column;
  }

  .status {
    text-align: left;
  }

  .badge {
    justify-content: center;
    width: 100%;
  }

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

  .example-table {
    display: block;
    overflow-x: auto;
    white-space: nowrap;
  }
}

@media (min-width: 768px) and (max-width: 1024px) {
  .translator-grid {
    grid-template-columns: 1fr;
  }

  .swap-column {
    padding-top: 0;
  }

  .swap-btn {
    transform: rotate(90deg);
  }
}