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

:root {
  --bg: #f8f9fa;
  --surface: #ffffff;
  --border: #e2e8f0;
  --accent: #3b6ff0;
  --accent-dark: #2d5cd4;
  --accent-light: #eef2fd;
  --text: #1a202c;
  --text-muted: #5a6474;
  --code-bg: #edf2f7;
  --code-text: #2d3748;
  --radius: 6px;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.07);
  --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

body {
  font-family:
    system-ui,
    -apple-system,
    'Segoe UI',
    Helvetica,
    Arial,
    sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  font-size: 16px;
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ─── NAV ─────────────────────────────────────────────────────────────────── */

.nav {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 20;
}

.nav-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  font-family: 'JetBrains Mono', 'Fira Code', 'Courier New', monospace;
  font-size: 17px;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-brand-dot {
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 50%;
  display: inline-block;
}

.nav-links {
  display: flex;
  gap: 24px;
  align-items: center;
}

.nav-links a {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-muted);
  text-decoration: none;
}

.nav-links a:hover {
  color: var(--text);
}

/* ─── HERO ────────────────────────────────────────────────────────────────── */

.hero {
  padding: 72px 0 80px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}

.hero .container {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: 64px;
  align-items: center;
}

.hero-logo {
  margin-bottom: 20px;
}

.hero h1 {
  font-size: 54px;
  font-weight: 700;
  line-height: 1.16;
  letter-spacing: -1.5px;
  color: var(--text);
  margin-bottom: 22px;
}

.hero-sub {
  font-size: 17px;
  color: var(--text-muted);
  line-height: 1.72;
  margin-bottom: 32px;
  max-width: 480px;
}

.hero-ctas {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  padding: 10px 22px;
  background: var(--accent);
  color: #fff;
  text-decoration: none;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 600;
  transition: background 0.15s;
}

.btn-primary:hover {
  background: var(--accent-dark);
  text-decoration: none;
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  padding: 10px 20px;
  background: transparent;
  color: var(--text);
  text-decoration: none;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 500;
  border: 1px solid var(--border);
  transition:
    border-color 0.15s,
    background 0.15s;
}

.btn-secondary:hover {
  background: var(--bg);
  border-color: #b8c4d8;
  text-decoration: none;
}

/* ─── ANIMATION SVG ───────────────────────────────────────────────────────── */

.hero-diagram {
  display: flex;
  justify-content: center;
  align-items: center;
}

#storage-svg {
  width: 100%;
  max-width: 680px;
  height: auto;
  overflow: visible;
}

#pfs-box,
#mount-box {
  transition:
    stroke 0.12s ease,
    stroke-width 0.12s ease;
}

/* ─── SECTION COMMON ──────────────────────────────────────────────────────── */

.section-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 10px;
}

.section-title {
  font-size: 26px;
  font-weight: 700;
  letter-spacing: -0.4px;
  margin-bottom: 36px;
  color: var(--text);
}

/* ─── FEATURES ────────────────────────────────────────────────────────────── */

.features {
  padding: 72px 0;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.feature-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 26px 22px;
  box-shadow: var(--shadow-sm);
}

.feature-icon {
  width: 34px;
  height: 34px;
  background: var(--accent-light);
  border-radius: 7px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 14px;
  font-size: 15px;
  color: var(--accent);
}

.feature-card h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text);
}

.feature-card p {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.65;
}

.feature-card code {
  font-family: 'JetBrains Mono', 'Fira Code', monospace;
  font-size: 12px;
  background: var(--code-bg);
  color: var(--code-text);
  padding: 1px 5px;
  border-radius: 3px;
}

/* ─── HOW IT WORKS ────────────────────────────────────────────────────────── */

.how-it-works {
  padding: 72px 0;
  background: var(--surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  position: relative;
}

.steps::before {
  content: '';
  position: absolute;
  top: 19px;
  left: calc(12.5% + 0px);
  right: calc(12.5% + 0px);
  height: 1px;
  background: var(--border);
  z-index: 0;
}

.step {
  text-align: center;
  padding: 0 14px;
  position: relative;
  z-index: 1;
}

.step-num {
  width: 38px;
  height: 38px;
  background: var(--surface);
  border: 2px solid var(--accent);
  color: var(--accent);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 700;
  margin: 0 auto 14px;
  font-family: 'JetBrains Mono', monospace;
}

.step h4 {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text);
}

.step p {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.55;
}

/* ─── COMPARISON ──────────────────────────────────────────────────────────── */

.comparison {
  padding: 72px 0;
}

.comparison-intro {
  max-width: 600px;
  color: var(--text-muted);
  font-size: 15px;
  line-height: 1.72;
  margin-bottom: 32px;
}

.comparison-table-wrap {
  overflow-x: auto;
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  background: var(--surface);
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}

.comparison-table th {
  background: var(--code-bg);
  padding: 11px 16px;
  text-align: left;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
  border-bottom: 1px solid var(--border);
}

.comparison-table th:not(:first-child) {
  text-align: center;
  width: 22%;
}
.comparison-table th:first-child {
  width: 56%;
}

.comparison-table td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--border);
  color: var(--text);
  vertical-align: middle;
}

.comparison-table td:not(:first-child) {
  text-align: center;
}
.comparison-table tr:last-child td {
  border-bottom: none;
}
.comparison-table tr:hover td {
  background: #f9fafc;
}

.check {
  color: #2d7a3a;
  font-weight: 700;
  font-size: 15px;
}
.partial {
  color: #92400e;
  font-size: 13px;
}
.cross {
  color: #9ca3af;
  font-size: 15px;
}

.comparison-caption {
  margin-top: 14px;
  font-size: 13px;
  color: var(--text-muted);
  font-style: italic;
}

/* ─── CONFIG SNIPPET ──────────────────────────────────────────────────────── */

.config-snippet {
  padding: 72px 0;
  background: var(--surface);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.snippet-wrap {
  max-width: 560px;
}

pre {
  background: #1e2433;
  color: #cdd6f4;
  border-radius: 8px;
  padding: 22px 26px;
  overflow-x: auto;
  font-size: 13px;
  line-height: 1.75;
  font-family: 'JetBrains Mono', 'Fira Code', 'Courier New', monospace;
  box-shadow: var(--shadow);
  margin-top: 16px;
}

.y-key {
  color: #89b4fa;
}
.y-str {
  color: #a6e3a1;
}
.y-num {
  color: #fab387;
}
.y-bool {
  color: #cba6f7;
}
.y-comment {
  color: #6c7086;
  font-style: italic;
}
.y-punct {
  color: #6c7086;
}

/* ─── INSTALL CTA ─────────────────────────────────────────────────────────── */

.install-cta {
  padding: 52px 0;
  background: var(--accent-light);
  border-top: 1px solid #c8d8f7;
  border-bottom: 1px solid #c8d8f7;
}

.install-cta .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  flex-wrap: wrap;
}

.install-cta h2 {
  font-size: 21px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 5px;
}

.install-cta p {
  font-size: 14px;
  color: var(--text-muted);
}

.install-cmd {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.install-cmd code {
  display: inline-block;
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--code-text);
  font-family: 'JetBrains Mono', monospace;
  font-size: 14px;
  padding: 8px 16px;
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
}

/* ─── FOOTER ──────────────────────────────────────────────────────────────── */

footer {
  padding: 36px 0;
  background: var(--surface);
  border-top: 1px solid var(--border);
}

footer .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-brand {
  font-family: 'JetBrains Mono', monospace;
  font-weight: 700;
  color: var(--text);
  text-decoration: none;
  font-size: 15px;
}

.footer-links {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  align-items: center;
}

.footer-links a {
  font-size: 13px;
  color: var(--text-muted);
  text-decoration: none;
}

.footer-links a:hover {
  color: var(--text);
}

.footer-copy {
  font-size: 12px;
  color: #9ca3af;
}

/* ─── RESPONSIVE ──────────────────────────────────────────────────────────── */

@media (max-width: 900px) {
  .hero .container {
    grid-template-columns: 1fr;
    gap: 44px;
  }

  .hero h1 {
    font-size: 38px;
  }
  .hero-sub {
    max-width: 100%;
  }

  #storage-svg {
    max-width: 560px;
  }

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

  .steps {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }

  .steps::before {
    display: none;
  }
}

@media (max-width: 520px) {
  .hero h1 {
    font-size: 30px;
  }
  .steps {
    grid-template-columns: 1fr;
  }

  .install-cta .container {
    flex-direction: column;
    align-items: flex-start;
  }

  footer .container {
    flex-direction: column;
    align-items: flex-start;
  }
}

/* ═══════════════════════════════════════════════════════════════════════════
   THEME TOGGLE BUTTON
═══════════════════════════════════════════════════════════════════════════ */

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  color: var(--text-muted);
  padding: 0;
  flex-shrink: 0;
  transition:
    border-color 0.15s,
    background-color 0.15s,
    color 0.15s;
}

.theme-toggle:hover {
  background: var(--bg);
  color: var(--text);
  border-color: #8a9ab8;
}

/* ═══════════════════════════════════════════════════════════════════════════
   DARK THEME
═══════════════════════════════════════════════════════════════════════════ */

/* tell the browser which native color scheme to use */
:root {
  color-scheme: light;
}
[data-theme='dark'] {
  color-scheme: dark;
}

[data-theme='dark'] {
  --bg: #0f1117;
  --surface: #161b27;
  --border: #252d3d;
  --accent-light: #1a2a4a;
  --text: #e2e8f0;
  --text-muted: #8a9ab8;
  --code-bg: #1e2433;
  --code-text: #cdd6f4;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.35);
  --shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
}

/* ── smooth transitions when switching themes ── */
body,
.nav,
.nav-links a,
.hero,
section,
.feature-card,
.step-num,
.comparison-table,
.comparison-table th,
.comparison-table td,
.install-cmd code,
footer {
  transition:
    background-color 0.18s ease,
    color 0.18s ease,
    border-color 0.18s ease;
}

/* ── hardcoded borders inside install-cta ── */
[data-theme='dark'] .install-cta {
  border-top-color: #1e3060;
  border-bottom-color: #1e3060;
}

/* ── table row hover ── */
[data-theme='dark'] .comparison-table tr:hover td {
  background: #1c2234;
}

/* ── secondary button ── */
[data-theme='dark'] .btn-secondary {
  color: var(--text);
}
[data-theme='dark'] .btn-secondary:hover {
  background: var(--surface);
}

/* ─────────────────────────────────────────────────────────────────────────
   Dark mode: inline SVG color overrides
   (CSS rules override SVG presentation attributes)
───────────────────────────────────────────────────────────────────────── */

/* ── hero logo icon (above H1) ── */
[data-theme='dark'] .hero-logo svg path[stroke='#dde3ed'] {
  stroke: #252d3d;
}
[data-theme='dark'] .hero-logo svg circle[fill='#94a3b8'] {
  fill: #5a6a84;
}

/* ── nav wordmark ── */
[data-theme='dark'] .nav-brand svg text {
  fill: var(--text);
}
[data-theme='dark'] .nav-brand svg path[stroke='#dde3ed'] {
  stroke: #252d3d;
}
[data-theme='dark'] .nav-brand svg circle[fill='#94a3b8'] {
  fill: #5a6a84;
}

/* ── footer wordmark ── */
[data-theme='dark'] .footer-brand svg text {
  fill: var(--text-muted);
}
[data-theme='dark'] .footer-brand svg path[stroke='#dde3ed'] {
  stroke: #252d3d;
}
[data-theme='dark'] .footer-brand svg circle[fill='#94a3b8'] {
  fill: #5a6a84;
}

/* ── animation diagram (#storage-svg) ── */

/* connector guide lines */
[data-theme='dark'] #storage-svg path[stroke='#dde3ed'] {
  stroke: #252d3d;
}

/* SSD group label */
[data-theme='dark'] #storage-svg text[fill='#2d7a3a'] {
  fill: #48bb78;
}

/* SSD boxes */
[data-theme='dark'] #storage-svg rect[fill='#edf7f1'] {
  fill: #182e22;
  stroke: #3d8a5a;
}

/* SSD text labels */
[data-theme='dark'] #storage-svg text[fill='#1f6333'] {
  fill: #48bb78;
}

/* HDD group label */
[data-theme='dark'] #storage-svg text[fill='#4a5568'] {
  fill: #6b7a94;
}

/* HDD boxes */
[data-theme='dark'] #storage-svg rect[fill='#edf0f7'] {
  fill: #1a2035;
  stroke: #5a7090;
}

/* HDD text labels + mount text */
[data-theme='dark'] #storage-svg text[fill='#2d3748'] {
  fill: #8a9ab8;
}

/* pfs daemon box background */
[data-theme='dark'] #storage-svg rect[fill='#ffffff'] {
  fill: #161b27;
}

/* pfs daemon detail labels */
[data-theme='dark'] #storage-svg text[fill='#6b7a94'] {
  fill: #7a8fa8;
}

/* unified mount box */
[data-theme='dark'] #storage-svg rect[fill='#f0f4ff'] {
  fill: #1a2544;
}