/* ============================================================
   itotii Markdown Editor — global styles
   Brand: itotii  |  Primary: teal #0FB3A7
   ============================================================ */

:root {
  --brand: #0fb3a7;
  --brand-dark: #0a8e85;
  --brand-light: #e6f7f5;
  --brand-soft: #f3fbfa;
  --text: #1f2933;
  --text-soft: #52606d;
  --text-mut: #7b8794;
  --bg: #ffffff;
  --bg-soft: #f7fafb;
  --bg-elev: #ffffff;
  --border: #e4e9ed;
  --border-strong: #cfd8de;
  --code-bg: #f3f5f7;
  --shadow: 0 6px 24px rgba(15, 179, 167, 0.10);
  --shadow-sm: 0 2px 8px rgba(31, 41, 51, 0.06);
  --radius: 12px;
  --radius-sm: 8px;
  --maxw: 1200px;
  --header-h: 64px;
  --mono: "SFMono-Regular", "JetBrains Mono", Consolas, "Liberation Mono", Menlo, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans",
    "Microsoft YaHei", "Noto Sans CJK SC", "Noto Sans JP", Roboto, Helvetica, Arial, sans-serif;
}

html[data-theme="dark"] {
  --brand: #21c9bc;
  --brand-dark: #0fb3a7;
  --brand-light: #0d2b29;
  --brand-soft: #0a1f1e;
  --text: #e6edf0;
  --text-soft: #b3bfc7;
  --text-mut: #8493a0;
  --bg: #0f1418;
  --bg-soft: #141b20;
  --bg-elev: #18222a;
  --border: #243039;
  --border-strong: #32424d;
  --code-bg: #1b262e;
  --shadow: 0 6px 24px rgba(0, 0, 0, 0.4);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: var(--sans);
  color: var(--text);
  background: var(--bg-soft);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: var(--brand-dark); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; }
:focus-visible { outline: 2px solid var(--brand); outline-offset: 2px; }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 0 20px;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; color: var(--text); }
.brand:hover { text-decoration: none; }
.brand .logo {
  width: 34px; height: 34px; border-radius: 9px;
  background: linear-gradient(135deg, var(--brand), var(--brand-dark));
  display: grid; place-items: center; color: #fff; font-weight: 800; font-size: 16px;
  box-shadow: var(--shadow-sm);
}
.brand small { display: block; font-size: 11px; font-weight: 500; color: var(--text-mut); letter-spacing: .04em; }
.header-spacer { flex: 1; }
.header-actions { display: flex; align-items: center; gap: 8px; }

/* language switcher */
.lang-switch { position: relative; }
.lang-btn {
  display: inline-flex; align-items: center; gap: 6px;
  height: 36px; padding: 0 12px; border-radius: 999px;
  border: 1px solid var(--border-strong); background: var(--bg-elev);
  color: var(--text); font-size: 13px; cursor: pointer; font-family: inherit;
}
.lang-btn:hover { border-color: var(--brand); }
.lang-menu {
  position: absolute; right: 0; top: calc(100% + 6px); min-width: 168px; z-index: 60;
  background: var(--bg-elev); border: 1px solid var(--border);
  border-radius: var(--radius-sm); box-shadow: var(--shadow); padding: 6px; display: none;
}
.lang-menu.open { display: block; }
.lang-menu button {
  display: flex; width: 100%; align-items: center; justify-content: space-between;
  padding: 9px 12px; border: 0; background: none; color: var(--text);
  font-size: 13px; cursor: pointer; border-radius: 6px; font-family: inherit; text-align: left;
}
.lang-menu button:hover { background: var(--brand-soft); }
.lang-menu button.active { color: var(--brand-dark); font-weight: 600; }

.icon-btn {
  width: 36px; height: 36px; border-radius: 9px; border: 1px solid var(--border-strong);
  background: var(--bg-elev); color: var(--text); cursor: pointer; display: grid; place-items: center;
}
.icon-btn:hover { border-color: var(--brand); color: var(--brand-dark); }
.icon-btn svg { width: 18px; height: 18px; }

/* ---------- Hero ---------- */
.hero { max-width: var(--maxw); margin: 0 auto; padding: 38px 20px 8px; text-align: center; }
.hero h1 { font-size: clamp(26px, 4vw, 40px); margin: 0 0 10px; letter-spacing: -.01em; }
.hero p.sub { font-size: clamp(15px, 2vw, 18px); color: var(--text-soft); margin: 0 auto; max-width: 720px; }
.hero .badges { margin-top: 14px; display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; }
.badge {
  font-size: 12px; color: var(--brand-dark); background: var(--brand-light);
  border: 1px solid color-mix(in srgb, var(--brand) 30%, transparent);
  padding: 4px 12px; border-radius: 999px;
}

/* ---------- Editor ---------- */
.editor-wrap { max-width: var(--maxw); margin: 18px auto 0; padding: 0 20px; }
.editor-card {
  background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
}
.toolbar {
  display: flex; align-items: center; gap: 4px; flex-wrap: wrap;
  padding: 8px 10px; border-bottom: 1px solid var(--border); background: var(--bg-soft);
  position: sticky; top: var(--header-h); z-index: 15;
  border-top-left-radius: calc(var(--radius) - 1px); border-top-right-radius: calc(var(--radius) - 1px);
}
.toolbar .group { display: flex; gap: 2px; align-items: center; }
.toolbar .sep { width: 1px; height: 22px; background: var(--border-strong); margin: 0 6px; }
.tbtn {
  min-width: 32px; height: 32px; padding: 0 8px; border: 0; background: none; cursor: pointer;
  border-radius: 6px; color: var(--text-soft); font-size: 14px; font-family: var(--mono);
  display: inline-grid; place-items: center;
}
.tbtn:hover { background: var(--brand-soft); color: var(--brand-dark); }
.tbtn svg { width: 16px; height: 16px; }
.toolbar .spacer { flex: 1; }
.outline-toggle { font-size: 13px; }

.panes { display: grid; grid-template-columns: 1fr 1fr; min-height: 460px; }
.pane { display: flex; flex-direction: column; min-width: 0; }
.pane.editor { border-right: 1px solid var(--border); }
.pane-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 8px 14px; font-size: 12px; color: var(--text-mut); text-transform: uppercase; letter-spacing: .06em;
  border-bottom: 1px solid var(--border); background: var(--bg-soft);
}
#md-input {
  flex: 1; width: 100%; border: 0; resize: none; padding: 18px; font-family: var(--mono);
  font-size: 14.5px; line-height: 1.7; color: var(--text); background: var(--bg-elev); tab-size: 2;
}
#md-input:focus { outline: none; }
#preview {
  flex: 1; overflow: auto; padding: 20px 24px; background: var(--bg);
}
#preview.mark-body { font-size: 15px; }
#preview.mark-body h1, #preview.mark-body h2, #preview.mark-body h3 { line-height: 1.3; margin: 1.4em 0 .6em; }
#preview.mark-body h1 { font-size: 1.9em; border-bottom: 1px solid var(--border); padding-bottom: .25em; }
#preview.mark-body h2 { font-size: 1.5em; border-bottom: 1px solid var(--border); padding-bottom: .2em; }
#preview.mark-body code { background: var(--code-bg); padding: .15em .4em; border-radius: 5px; font-size: .9em; font-family: var(--mono); }
#preview.mark-body pre { background: var(--code-bg); padding: 14px 16px; border-radius: var(--radius-sm); overflow: auto; }
#preview.mark-body pre code { background: none; padding: 0; }
#preview.mark-body blockquote { border-left: 4px solid var(--brand); margin: 1em 0; padding: .2em 1em; color: var(--text-soft); background: var(--brand-soft); border-radius: 0 8px 8px 0; }
#preview.mark-body table { border-collapse: collapse; width: 100%; margin: 1em 0; }
#preview.mark-body th, #preview.mark-body td { border: 1px solid var(--border); padding: 8px 12px; }
#preview.mark-body th { background: var(--bg-soft); }
#preview.mark-body img { border-radius: 8px; }
#preview.mark-body a { word-break: break-word; }
#preview.mark-body hr { border: 0; border-top: 1px solid var(--border); margin: 2em 0; }

.statusbar {
  display: flex; align-items: center; gap: 16px; flex-wrap: wrap;
  padding: 8px 14px; border-top: 1px solid var(--border); background: var(--bg-soft);
  font-size: 12px; color: var(--text-mut);
  border-bottom-left-radius: calc(var(--radius) - 1px); border-bottom-right-radius: calc(var(--radius) - 1px);
}
.statusbar .save-state { margin-left: auto; display: inline-flex; align-items: center; gap: 6px; }
.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--brand); }

/* drag overlay */
.drop-overlay {
  position: fixed; inset: 0; z-index: 200; display: none;
  align-items: center; justify-content: center;
  background: color-mix(in srgb, var(--brand) 22%, transparent); backdrop-filter: blur(3px);
}
.drop-overlay.show { display: flex; }
.drop-overlay .box {
  border: 3px dashed var(--brand); border-radius: 18px; padding: 50px 70px;
  background: var(--bg-elev); color: var(--brand-dark); font-size: 20px; font-weight: 700; text-align: center;
}

/* outline drawer */
.outline {
  position: absolute; z-index: 30; right: 24px; top: 70px; width: 240px;
  background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius-sm);
  box-shadow: var(--shadow); padding: 10px 12px; display: none; max-height: 60vh; overflow: auto;
}
.outline.show { display: block; }
.outline a { display: block; padding: 5px 8px; border-radius: 6px; color: var(--text-soft); font-size: 13px; }
.outline a:hover { background: var(--brand-soft); color: var(--brand-dark); text-decoration: none; }
.outline a.lv2 { padding-left: 20px; }
.outline a.lv3 { padding-left: 34px; }

/* ---------- Features ---------- */
.section { max-width: var(--maxw); margin: 46px auto; padding: 0 20px; }
.section h2 { font-size: clamp(22px, 3vw, 30px); text-align: center; margin: 0 0 8px; }
.section p.lead { text-align: center; color: var(--text-soft); max-width: 640px; margin: 0 auto 28px; }
.feature-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 16px; }
.feature {
  background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px; box-shadow: var(--shadow-sm); transition: transform .15s, box-shadow .15s;
}
.feature:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.feature .ico { width: 42px; height: 42px; border-radius: 11px; background: var(--brand-soft); color: var(--brand-dark); display: grid; place-items: center; margin-bottom: 12px; }
.feature h3 { margin: 0 0 6px; font-size: 16px; }
.feature p { margin: 0; font-size: 13.5px; color: var(--text-soft); }

/* ---------- FAQ (GEO) ---------- */
.faq { max-width: 820px; margin: 0 auto; }
.faq details { background: var(--bg-elev); border: 1px solid var(--border); border-radius: var(--radius-sm); margin-bottom: 12px; padding: 4px 18px; }
.faq summary { cursor: pointer; font-weight: 600; padding: 14px 0; list-style: none; display: flex; justify-content: space-between; align-items: center; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--brand-dark); font-size: 20px; }
.faq details[open] summary::after { content: "−"; }
.faq .answer { padding: 0 0 16px; color: var(--text-soft); font-size: 14.5px; }

/* ---------- Footer ---------- */
.site-footer { background: var(--bg-elev); border-top: 1px solid var(--border); margin-top: 54px; }
.footer-inner { max-width: var(--maxw); margin: 0 auto; padding: 36px 20px 22px; }
.footer-links-title { font-size: 14px; font-weight: 700; color: var(--text); margin: 0 0 14px; }
.friend-links { display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 10px 18px; }
.friend-links a {
  display: inline-flex; align-items: center; gap: 8px; font-size: 13.5px; color: var(--text-soft);
}
.friend-links a:hover { color: var(--brand-dark); text-decoration: none; }
.friend-links a .fl-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--brand); flex: none; }
.footer-bottom {
  border-top: 1px solid var(--border); margin-top: 26px; padding-top: 18px;
  display: flex; flex-wrap: wrap; gap: 10px 20px; align-items: center; justify-content: space-between;
  font-size: 12.5px; color: var(--text-mut);
}
.footer-bottom .fb-links a { color: var(--text-mut); margin-left: 16px; }
.footer-bottom .fb-links a:first-child { margin-left: 0; }

/* ---------- Responsive ---------- */
@media (max-width: 820px) {
  .panes { grid-template-columns: 1fr; }
  .pane.editor { border-right: 0; border-bottom: 1px solid var(--border); }
  .outline { right: 12px; }
  .brand small { display: none; }
}

/* toast */
.toast {
  position: fixed; left: 50%; bottom: 28px; transform: translateX(-50%) translateY(20px);
  background: var(--text); color: #fff; padding: 10px 18px; border-radius: 999px; font-size: 13.5px;
  box-shadow: var(--shadow); opacity: 0; pointer-events: none; transition: all .25s; z-index: 300;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }