:root {
  --font-sans: "Source Sans 3", "Segoe UI", -apple-system, BlinkMacSystemFont, sans-serif;
  --bg: #f4f8f8;
  --panel: #ffffff;
  --panel-soft: #f9fcfc;
  --text: #17313a;
  --muted: #5d737d;
  --border: #d7e3e4;
  --border-strong: #bdd0d3;
  --accent: #0f766e;
  --accent-strong: #115e59;
  --accent-soft: #e2f4f1;
  --danger: #b42318;
  --shadow-soft: 0 8px 22px rgba(18, 42, 47, 0.05);
  color-scheme: light;
}

:root[data-theme="dark"] {
  --bg: #0f1a1e;
  --panel: #132127;
  --panel-soft: #182a31;
  --text: #eef7f7;
  --muted: #9fb2b8;
  --border: #24353c;
  --border-strong: #31515a;
  --accent: #5cc3bc;
  --accent-strong: #78d6cf;
  --accent-soft: rgba(92, 195, 188, 0.14);
  --danger: #ff8f7e;
  --shadow-soft: 0 8px 22px rgba(0, 0, 0, 0.2);
  color-scheme: dark;
}

* {
  box-sizing: border-box;
}

html {
  min-height: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-sans);
  color: var(--text);
  background:
    radial-gradient(circle at top right, rgba(92, 195, 188, 0.14), transparent 30%),
    radial-gradient(circle at bottom left, rgba(15, 118, 110, 0.08), transparent 26%),
    var(--bg);
}

p {
  margin: 0;
}

a {
  color: inherit;
}

button,
input,
select {
  font: inherit;
}

button {
  cursor: pointer;
}

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

.site-shell {
  width: min(1080px, calc(100% - 2rem));
  margin: 0 auto;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.2rem 0 0;
}

.brand {
  text-decoration: none;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.4rem;
  height: 2.4rem;
  border-radius: 0.85rem;
  background: var(--accent-soft);
  color: var(--accent-strong);
  font-weight: 700;
  letter-spacing: 0.02em;
}

.brand-row {
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

.brand-copy {
  display: flex;
  flex-direction: column;
  gap: 0.05rem;
}

.brand-title {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.brand-subtitle {
  color: var(--muted);
  font-size: 0.95rem;
}

.brand-subtitle-page {
  color: var(--text);
  font-weight: 600;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.page-main {
  padding: 2.2rem 0 3rem;
}

.hero {
  display: grid;
  gap: 0.85rem;
  margin-bottom: 1.5rem;
}

.eyebrow {
  display: inline-flex;
  width: fit-content;
  align-items: center;
  gap: 0.45rem;
  padding: 0.38rem 0.72rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.42);
  color: var(--muted);
  font-size: 0.9rem;
}

.page-title {
  margin: 0;
  font-size: clamp(2rem, 4vw, 3.15rem);
  line-height: 1.05;
  letter-spacing: -0.035em;
}

.page-lead {
  margin: 0;
  max-width: 44rem;
  color: var(--muted);
  font-size: 1.07rem;
  line-height: 1.6;
}

.card,
.app-card,
.result-card,
.note-card {
  border: 1px solid var(--border);
  border-radius: 1.1rem;
  background: var(--panel);
  box-shadow: var(--shadow-soft);
}

.card,
.result-card,
.note-card {
  padding: 1.2rem;
}

.directory-grid,
.tool-grid,
.stats-grid,
.pair-grid {
  display: grid;
  gap: 1rem;
}

.directory-grid {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.stats-grid {
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
}

.pair-grid {
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 0.75rem;
}

.tool-grid {
  grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.9fr);
  grid-template-areas:
    "form result"
    "form details";
  align-items: start;
}

.tool-form-card {
  grid-area: form;
}

.tool-result-card {
  grid-area: result;
}

.tool-details {
  grid-area: details;
}

.app-card {
  display: grid;
  gap: 0.9rem;
  padding: 1.25rem;
}

.app-card h2,
.card h2,
.result-card h2,
.note-card h2 {
  margin: 0;
  font-size: 1.28rem;
  letter-spacing: -0.02em;
}

.muted {
  color: var(--muted);
}

.button,
.button-secondary,
.theme-toggle,
.swap-button,
.quick-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.45rem;
  border-radius: 0.9rem;
  border: 1px solid transparent;
  text-decoration: none;
  transition:
    background-color 160ms ease,
    border-color 160ms ease,
    color 160ms ease,
    transform 160ms ease,
    box-shadow 160ms ease;
}

.button,
.button-secondary,
.theme-toggle,
.swap-button {
  min-height: 2.9rem;
  padding: 0.78rem 1rem;
}

.button {
  background: var(--accent);
  color: #f7ffff;
  box-shadow: 0 10px 22px rgba(15, 118, 110, 0.18);
}

.button:hover,
.button:focus-visible {
  background: var(--accent-strong);
}

.button-secondary,
.theme-toggle,
.quick-button {
  background: var(--panel-soft);
  border-color: var(--border);
  color: var(--text);
}

.swap-button-utility {
  background: var(--accent-soft);
  border-color: var(--border-strong);
  color: var(--accent-strong);
  font-weight: 600;
  box-shadow: inset 0 0 0 1px rgba(15, 118, 110, 0.06);
}

.button-secondary:hover,
.button-secondary:focus-visible,
.theme-toggle:hover,
.theme-toggle:focus-visible,
.quick-button:hover,
.quick-button:focus-visible {
  border-color: var(--border-strong);
  background: var(--accent-soft);
}

.swap-button-utility:hover,
.swap-button-utility:focus-visible {
  border-color: var(--accent);
  background: rgba(15, 118, 110, 0.12);
}

.button:focus-visible,
.button-secondary:focus-visible,
.theme-toggle:focus-visible,
.swap-button:focus-visible,
.quick-button:focus-visible,
.input:focus-visible,
.select:focus-visible {
  outline: 3px solid rgba(15, 118, 110, 0.18);
  outline-offset: 2px;
}

.stack {
  display: grid;
  gap: 1rem;
}

.cluster {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-items: center;
}

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

.field {
  display: grid;
  gap: 0.45rem;
}

.label-row {
  display: flex;
  justify-content: space-between;
  gap: 0.75rem;
  align-items: baseline;
}

.label {
  font-weight: 600;
}

.hint {
  color: var(--muted);
  font-size: 0.94rem;
}

.input,
.select {
  width: 100%;
  min-height: 3rem;
  border-radius: 0.9rem;
  border: 1px solid var(--border);
  background: var(--panel-soft);
  color: var(--text);
  padding: 0.8rem 0.95rem;
}

.input[type="number"] {
  appearance: textfield;
}

.input::-webkit-outer-spin-button,
.input::-webkit-inner-spin-button {
  appearance: none;
  margin: 0;
}

.quick-button {
  min-height: 2.6rem;
  padding: 0.65rem 0.85rem;
}

.swap-row {
  display: flex;
  justify-content: center;
}

.swap-button {
  min-width: 3rem;
}

.result-number {
  margin: 0;
  font-size: clamp(2rem, 5vw, 3rem);
  line-height: 1;
  letter-spacing: -0.04em;
}

.result-meta {
  margin: 0;
  color: var(--muted);
  line-height: 1.55;
}

.status {
  min-height: 1.4rem;
  margin: 0;
  color: var(--muted);
}

.status[data-state="error"] {
  color: var(--danger);
}

.stat {
  display: grid;
  gap: 0.2rem;
  padding: 0.95rem 1rem;
  border-radius: 0.95rem;
  border: 1px solid var(--border);
  background: var(--panel-soft);
}

.stat-label {
  color: var(--muted);
  font-size: 0.95rem;
}

.stat-value {
  font-size: 1.08rem;
  font-weight: 600;
}

.inline-link {
  color: var(--accent-strong);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.15em;
}

.site-footer {
  padding: 0 0 2.2rem;
  color: var(--muted);
  font-size: 0.96rem;
}

.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: 820px) {
  .tool-grid {
    grid-template-columns: 1fr;
    grid-template-areas:
      "result"
      "form"
      "details";
  }
}

@media (max-width: 640px) {
  .site-shell {
    width: min(100% - 1rem, 100%);
  }

  .site-header {
    padding-top: 0.8rem;
  }

  .brand-row {
    align-items: flex-start;
  }

  .brand-subtitle {
    display: none;
  }

  .brand-subtitle-page {
    display: block;
    font-size: 0.86rem;
    color: var(--muted);
  }

  .page-main {
    padding-top: 1.4rem;
  }

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