@import url("https://fonts.googleapis.com/css2?family=Playfair+Display:wght@600;700&family=Inter:wght@400;500;600;700&display=swap");

:root {
  --bg-page: #f7f5f0;
  --bg-card: #ffffff;
  --bg-card-alt: #f0ece2;
  --border: rgba(15, 30, 51, 0.12);
  --text-heading: #16293f;
  --text-body: #33465c;
  --text-muted: #6b7889;
  --accent: #1f8f80;
  --accent-strong: #167568;
  --on-accent: #ffffff;
  --radius-lg: 20px;
  --radius-md: 14px;
  --radius-sm: 9px;
  --shadow: 0 20px 50px -25px rgba(15, 30, 51, 0.35);
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg-page: #0f1e33;
    --bg-card: #182a44;
    --bg-card-alt: #1f3350;
    --border: rgba(255, 255, 255, 0.1);
    --text-heading: #f4efe3;
    --text-body: #d7dee8;
    --text-muted: #8b96aa;
    --accent: #46b8a8;
    --accent-strong: #5fcab9;
    --on-accent: #082621;
    --shadow: 0 20px 50px -20px rgba(0, 0, 0, 0.6);
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg-page);
  color: var(--text-body);
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 {
  font-family: "Playfair Display", Georgia, serif;
  color: var(--text-heading);
  margin: 0 0 0.4em;
  line-height: 1.15;
}

p { margin: 0 0 1em; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

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

.container {
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ---- Nav ---- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--bg-page) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.site-nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 14px;
  padding-bottom: 14px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: "Playfair Display", Georgia, serif;
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--text-heading);
}
.brand img { width: 32px; height: 32px; border-radius: 8px; }
.nav-links { display: flex; align-items: center; gap: 24px; }
.nav-links a { color: var(--text-body); font-weight: 500; font-size: 0.95rem; }
.nav-links a:hover { color: var(--accent); text-decoration: none; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid transparent;
  cursor: pointer;
}
.btn-primary { background: var(--accent); color: var(--on-accent); }
.btn-primary:hover { background: var(--accent-strong); text-decoration: none; }
.btn-ghost { background: transparent; border-color: var(--border); color: var(--text-heading); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }

/* ---- Hero ---- */
.hero {
  padding: 72px 0 48px;
  text-align: center;
}
.hero .eyebrow {
  display: inline-block;
  font-weight: 600;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 14px;
}
.hero h1 { font-size: clamp(2.1rem, 5vw, 3.4rem); }
.hero .lede {
  max-width: 640px;
  margin: 18px auto 30px;
  font-size: 1.1rem;
  color: var(--text-body);
}
.hero .cta-row {
  display: flex;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
}

.coming-soon {
  max-width: 560px;
  margin: 34px auto 0;
  padding: 14px 20px;
  border: 1px dashed var(--border);
  border-radius: var(--radius-md);
  color: var(--text-muted);
  font-size: 0.92rem;
}

/* ---- Sections ---- */
section { padding: 56px 0; }
.section-head { text-align: center; max-width: 640px; margin: 0 auto 40px; }
.section-head h2 { font-size: clamp(1.6rem, 3.4vw, 2.2rem); }
.section-head p { color: var(--text-muted); }

/* ---- Feature grid ---- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 20px;
}
.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 26px;
  box-shadow: var(--shadow);
}
.feature-card .icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: color-mix(in srgb, var(--accent) 16%, transparent);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  margin-bottom: 14px;
}
.feature-card h3 { font-size: 1.1rem; margin-bottom: 8px; }
.feature-card p { color: var(--text-muted); font-size: 0.95rem; margin: 0; }

/* ---- Mode showcase (screenshot strip) ---- */
.mode-showcase {
  display: flex;
  flex-direction: column;
  gap: 64px;
}
.mode-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
  align-items: center;
}
.mode-row:nth-child(even) .mode-copy { order: 2; }
.mode-row .eyebrow {
  display: block;
  font-weight: 600;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 10px;
}
.mode-row h3 { font-size: 1.6rem; margin-bottom: 12px; }
.mode-row p { color: var(--text-body); }
.mode-row .shot {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
  justify-self: center;
  max-width: 320px;
}

@media (max-width: 760px) {
  .mode-row { grid-template-columns: 1fr; }
  .mode-row:nth-child(even) .mode-copy { order: 0; }
  .mode-row .shot { order: -1; }
}

/* ---- FAQ ---- */
.faq { max-width: 720px; margin: 0 auto; }
.faq details {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  margin-bottom: 12px;
  background: var(--bg-card);
}
.faq summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--text-heading);
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; float: right; color: var(--accent); font-weight: 700; }
.faq details[open] summary::after { content: "\2212"; }
.faq details p { margin-top: 12px; color: var(--text-body); }

/* ---- Footer ---- */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 32px 0;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.88rem;
}

/* ================= convert.html ================= */

.tool-header { padding: 40px 0 8px; text-align: center; }
.tool-header h1 { font-size: clamp(1.8rem, 4vw, 2.4rem); }
.tool-header p { color: var(--text-muted); max-width: 560px; margin: 0 auto; }

.tool-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: 26px;
  margin-bottom: 22px;
}
.tool-card h2 {
  font-family: "Inter", sans-serif;
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  font-weight: 600;
  margin-bottom: 16px;
}

.field-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
  margin-bottom: 14px;
}
.field { display: flex; flex-direction: column; gap: 6px; }
.field label { font-size: 0.85rem; font-weight: 600; color: var(--text-heading); }
.field input, .field select {
  font: inherit;
  padding: 11px 13px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--bg-card-alt);
  color: var(--text-heading);
}
.field input:focus, .field select:focus { outline: 2px solid var(--accent); outline-offset: 1px; }

.hidden { display: none !important; }

.note {
  font-size: 0.86rem;
  color: var(--text-muted);
  background: var(--bg-card-alt);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  margin-bottom: 16px;
}

.mode-tabs {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 10px;
  margin-bottom: 20px;
}
.mode-tab {
  font: inherit;
  font-weight: 600;
  font-size: 0.85rem;
  padding: 14px 8px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg-card-alt);
  color: var(--text-body);
  cursor: pointer;
  text-align: center;
}
.mode-tab.active { background: var(--accent); color: var(--on-accent); border-color: var(--accent); }
@media (max-width: 700px) {
  .mode-tabs { grid-template-columns: repeat(3, 1fr); }
}

.calc-record { border-top: 1px solid var(--border); padding-top: 14px; margin-top: 14px; }
.calc-record h3 { font-family: "Inter", sans-serif; font-size: 0.9rem; margin: 0 0 10px; color: var(--text-heading); }
.calc-op-row { display: flex; gap: 10px; align-items: center; margin: 14px 0; }
.calc-op {
  font: inherit;
  font-weight: 700;
  width: 44px;
  height: 44px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--bg-card-alt);
  color: var(--text-body);
  cursor: pointer;
}
.calc-op.active { background: var(--accent); color: var(--on-accent); border-color: var(--accent); }

.result-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
  padding: 12px 4px;
  border-bottom: 1px solid var(--border);
}
.result-row:last-child { border-bottom: none; }
.result-row.is-active .result-label { color: var(--accent); font-weight: 700; }
.result-row.is-dim { opacity: 0.45; }
.result-label { font-weight: 600; color: var(--text-heading); }
.result-detail { display: block; font-weight: 400; font-size: 0.78rem; color: var(--text-muted); margin-top: 2px; }
.result-value { font-variant-numeric: tabular-nums; font-weight: 600; color: var(--text-heading); white-space: nowrap; }

.reference-row {
  display: grid;
  grid-template-columns: minmax(120px, 220px) 1fr;
  gap: 14px;
  padding: 10px 4px;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
}
.reference-row:last-child { border-bottom: none; }
.reference-label { font-weight: 600; color: var(--text-heading); }
.reference-value { color: var(--text-body); }

.caution-note {
  white-space: pre-line;
  font-size: 0.86rem;
  color: var(--text-muted);
}

.footer-note {
  font-size: 0.82rem;
  color: var(--text-muted);
  text-align: center;
  max-width: 720px;
  margin: 0 auto;
}