:root {
  --bg: #0f1210;
  --surface: #171b18;
  --surface-2: #1e241f;
  --border: #2a322c;
  --text: #e8ece8;
  --muted: #98a39a;
  --accent: #6cc04a;
  --accent-ink: #0c1a07;
  --accent-soft: rgba(108, 192, 74, 0.12);
  --warn: #e0b341;
  --error: #ef6b5b;
  --radius: 14px;
  color-scheme: dark;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #f6f7f4;
    --surface: #ffffff;
    --surface-2: #f0f2ee;
    --border: #dde2da;
    --text: #18201a;
    --muted: #5d685f;
    --accent: #3f8f22;
    --accent-ink: #ffffff;
    --accent-soft: rgba(63, 143, 34, 0.1);
    --warn: #9a6b00;
    --error: #c23b2b;
    color-scheme: light;
  }
}

* { box-sizing: border-box; }

[hidden] { display: none !important; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 Inter, system-ui, sans-serif;
  -webkit-font-smoothing: antialiased;
}

.mono, code { font-family: "JetBrains Mono", ui-monospace, monospace; }
code { font-size: 0.9em; background: var(--surface-2); padding: 0.1em 0.35em; border-radius: 5px; }

a { color: inherit; }

.wrap { width: 100%; max-width: 1160px; margin: 0 auto; padding: 0 20px; }

/* Header */
.top { border-bottom: 1px solid var(--border); position: sticky; top: 0; background: color-mix(in srgb, var(--bg) 85%, transparent); backdrop-filter: blur(10px); z-index: 10; }
.top-inner { display: flex; align-items: center; justify-content: space-between; height: 60px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 700; text-decoration: none; letter-spacing: -0.01em; }
.logo-block {
  width: 18px; height: 18px; border-radius: 3px;
  background: linear-gradient(var(--accent) 0 35%, #7a5534 35% 100%);
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.25);
}
nav { display: flex; gap: 22px; }
nav a { color: var(--muted); text-decoration: none; font-size: 15px; }
nav a:hover { color: var(--text); }

/* Layout: one column — intro, converter, features, footer. */
.layout { padding-top: 56px; }
.intro { padding-bottom: 32px; }

/* Hero */
.eyebrow { color: var(--accent); font-size: 13px; margin: 0 0 16px; }
h1 { font-size: clamp(34px, 5vw, 54px); line-height: 1.08; letter-spacing: -0.03em; margin: 0 0 20px; }
.lead { color: var(--muted); font-size: 18px; margin: 0; }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  height: 44px; padding: 0 20px; border-radius: 10px;
  font: 600 15px/1 Inter, system-ui, sans-serif; text-decoration: none;
  border: 1px solid transparent; cursor: pointer;
  transition: transform 0.12s ease, background-color 0.15s ease, opacity 0.15s ease;
}
.btn:active:not(:disabled) { transform: scale(0.98); }
.btn.primary { background: var(--accent); color: var(--accent-ink); }
.btn.primary:hover:not(:disabled) { background: color-mix(in srgb, var(--accent) 88%, white); }
.btn:disabled { opacity: 0.55; cursor: not-allowed; }
.btn.wide { width: 100%; }
.btn:focus-visible, select:focus-visible, .mode-btn:focus-visible, .drop:focus-within { outline: 2px solid var(--accent); outline-offset: 2px; }

/* Tool */
.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); }
.tool { padding: 24px; display: grid; gap: 18px; }

.mode { display: grid; grid-template-columns: 1fr 1fr; padding: 4px; background: var(--surface-2); border-radius: 10px; }
.mode-btn {
  border: 0; background: transparent; color: var(--muted);
  font: 600 15px/1 Inter, system-ui, sans-serif; padding: 12px 16px; border-radius: 7px; cursor: pointer;
}
.mode-btn[aria-selected="true"] { background: var(--surface); color: var(--text); box-shadow: 0 1px 2px rgba(0, 0, 0, 0.2); }

.drop {
  display: grid; justify-items: center; gap: 6px; text-align: center;
  padding: 36px 16px; border: 1.5px dashed var(--border); border-radius: 12px;
  cursor: pointer; transition: border-color 0.15s ease, background-color 0.15s ease;
}
.drop:hover, .drop.over { border-color: var(--accent); background: var(--accent-soft); }
.drop.has-file { border-style: solid; border-color: var(--accent); }
.drop-icon {
  width: 34px; height: 34px; margin-bottom: 6px; border-radius: 6px;
  background: linear-gradient(var(--accent) 0 35%, #7a5534 35% 100%);
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.25);
}
.drop-title { font-weight: 600; word-break: break-all; }
.drop-hint { color: var(--muted); font-size: 14px; }

.fields { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.fields label { display: grid; gap: 6px; font-size: 14px; color: var(--muted); }
select {
  width: 100%; min-width: 0;
  height: 44px; padding: 0 12px; border-radius: 10px; border: 1px solid var(--border);
  background: var(--surface-2); color: var(--text); font: 15px Inter, system-ui, sans-serif;
}
.mode-note { margin: 0; color: var(--muted); font-size: 14px; }
.note { margin: 0; padding-left: 12px; border-left: 2px solid var(--warn); color: var(--muted); font-size: 13px; line-height: 1.5; }
.note strong { color: var(--text); font-weight: 600; }

.status { font-size: 14px; color: var(--muted); min-height: 1.6em; }
.status:empty { display: none; }
.status.error { color: var(--error); }
.status.busy::before {
  content: ""; display: inline-block; width: 12px; height: 12px; margin-right: 8px; vertical-align: -1px;
  border: 2px solid var(--border); border-top-color: var(--accent); border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.result { border-top: 1px solid var(--border); padding-top: 18px; display: grid; gap: 10px; }
.result-head { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
.result-title { margin: 0; font-weight: 600; }
.result-meta { margin: 2px 0 0; font-size: 13px; color: var(--muted); }
details { background: var(--surface-2); border-radius: 10px; padding: 10px 14px; }
summary { cursor: pointer; font-weight: 600; font-size: 14px; }
.count { color: var(--muted); font-weight: 400; }
#warnings-box summary { color: var(--warn); }
.list { margin: 10px 0 2px; padding-left: 18px; font-size: 13px; color: var(--muted); max-height: 260px; overflow: auto; }
.list li + li { margin-top: 4px; }

/* Features */
.features { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; padding-top: 48px; padding-bottom: 24px; }
.features article { padding: 20px; border: 1px solid var(--border); border-radius: var(--radius); }
.features h3 { margin: 0 0 6px; font-size: 16px; }
.features p { margin: 0; color: var(--muted); font-size: 14px; }

.foot {
  display: flex; justify-content: space-between; align-items: baseline; gap: 8px 24px; flex-wrap: wrap;
  margin-top: 24px; border-top: 1px solid var(--border); padding: 16px 0 24px; color: var(--muted); font-size: 13px;
}
.foot p { margin: 0; }
.foot p:last-child { white-space: nowrap; }

@media (max-width: 900px) {
  .layout { padding-top: 32px; }
  .features { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 560px) {
  .features { grid-template-columns: 1fr; }
  .fields { grid-template-columns: 1fr; }
  .lead { font-size: 16px; }
  .tool { padding: 18px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn, .drop { transition: none; }
  .status.busy::before { animation-duration: 2.4s; }
}