/* 「目标」官网 · 黑白极简 · 不依赖任何外部字体、脚本或统计 */

:root {
  --bg: #fafafa;
  --fg: #111111;
  --muted: #5c5c5c;
  --line: #e6e6e6;
  --btn: #111111;
  --btn-fg: #fafafa;
  --serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", "Times New Roman", serif;
  --sans: "Source Han Sans SC", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --mono: "SFMono-Regular", "Menlo", "Consolas", "Liberation Mono", monospace;
  --measure: 40rem;
  --pad: 1.25rem;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.7;
  -webkit-text-size-adjust: 100%;
  text-rendering: optimizeLegibility;
}

html[data-lang="zh"] .en,
html:not([data-lang]) .en { display: none; }
html[data-lang="en"] .zh { display: none; }

html[data-lang="en"] body { line-height: 1.65; }

img { max-width: 100%; height: auto; border: 0; display: block; }

a {
  color: var(--fg);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

a:hover { opacity: 0.7; }

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--fg);
  outline-offset: 3px;
}

.skip {
  position: absolute;
  left: 0.75rem;
  top: -3rem;
  background: var(--fg);
  color: var(--bg);
  padding: 0.4rem 0.7rem;
  z-index: 20;
}
.skip:focus { top: 0.75rem; }

.wrap {
  width: min(var(--measure), calc(100% - 2 * var(--pad)));
  margin-inline: auto;
}

/* Header */
.site-header {
  border-bottom: 1px solid var(--line);
  background: var(--bg);
}

.header-inner {
  width: min(56rem, calc(100% - 2 * var(--pad)));
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  min-height: 3.5rem;
  padding: 0.4rem 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  flex-shrink: 0;
}

.brand img {
  width: 28px;
  height: 28px;
  border-radius: 6px;
}

.brand-name {
  font-family: var(--serif);
  font-size: 1.05rem;
  letter-spacing: 0.12em;
}

.nav {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.15rem 0.9rem;
  font-size: 0.82rem;
  letter-spacing: 0.04em;
}

.nav a { text-decoration: none; color: var(--muted); }
.nav a:hover,
.nav a[aria-current="page"] { color: var(--fg); }

.lang-btn {
  margin: 0;
  padding: 0;
  border: 0;
  background: none;
  color: var(--muted);
  font: inherit;
  font-size: 0.82rem;
  letter-spacing: 0.04em;
  cursor: pointer;
}
.lang-btn:hover { color: var(--fg); }

/* Hero */
.hero {
  padding: 3.5rem 0 3rem;
  text-align: center;
}

.hero-icon {
  width: 96px;
  height: 96px;
  margin: 0 auto 1.6rem;
  border-radius: 22px;
}

.hero h1 {
  margin: 0;
  font-family: var(--serif);
  font-weight: 600;
  font-size: 2.4rem;
  letter-spacing: 0.28em;
  line-height: 1.2;
  text-indent: 0.28em; /* optical center with letter-spacing */
}

.hero .en-name {
  margin: 0.45rem 0 0;
  color: var(--muted);
  font-size: 0.82rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
}

.motto {
  margin: 1.6rem 0 0;
  font-family: var(--serif);
  font-size: 1.15rem;
  line-height: 1.8;
}

.tagline {
  margin: 0.7rem 0 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.cta-row {
  margin-top: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.6rem;
}

.btn {
  display: inline-block;
  background: var(--btn);
  color: var(--btn-fg);
  text-decoration: none;
  padding: 0.75rem 1.6rem;
  min-width: 12.5rem;
  text-align: center;
  font-size: 0.95rem;
  letter-spacing: 0.08em;
  border: 1px solid var(--btn);
}

.btn:hover { opacity: 1; background: #000; }

.btn-ghost {
  background: transparent;
  color: var(--fg);
  border-color: var(--fg);
}

.btn-ghost:hover { background: var(--fg); color: var(--bg); opacity: 1; }

.cta-note {
  color: var(--muted);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
}

/* Features */
.features {
  padding: 0 0 3.5rem;
  border-top: 0;
}

.feature-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
}

.feature-list li {
  padding: 0.95rem 0;
  border-bottom: 1px solid var(--line);
  font-size: 0.98rem;
}

.feature-list .k {
  display: block;
  font-family: var(--serif);
  margin-bottom: 0.15rem;
}

.feature-list .d {
  color: var(--muted);
  font-size: 0.88rem;
}

/* Page body (download, legal) */
.page {
  padding: 2.2rem 0 3.5rem;
}

.page h1 {
  margin: 0 0 0.4rem;
  font-family: var(--serif);
  font-weight: 600;
  font-size: 1.7rem;
  letter-spacing: 0.08em;
  line-height: 1.35;
}

.lead, .meta-line {
  color: var(--muted);
  margin: 0 0 1.6rem;
  font-size: 0.92rem;
}

.page h2 {
  margin: 2.1rem 0 0.6rem;
  font-family: var(--serif);
  font-weight: 600;
  font-size: 1.15rem;
  letter-spacing: 0.06em;
}

.page h3 {
  margin: 1.3rem 0 0.4rem;
  font-size: 1rem;
  font-weight: 600;
}

.page p { margin: 0.7rem 0; }
.page ul, .page ol { margin: 0.5rem 0 0.9rem; padding-left: 1.2rem; }
.page li { margin: 0.28rem 0; }

.page table {
  width: 100%;
  max-width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  margin: 0.8rem 0 1.2rem;
  table-layout: fixed;
}

.page th, .page td {
  text-align: left;
  vertical-align: top;
  padding: 0.65rem 0.55rem 0.65rem 0;
  border-bottom: 1px solid var(--line);
  overflow-wrap: anywhere;
}

.page th:first-child,
.page td:first-child { width: 36%; padding-right: 0.8rem; }

.page th {
  font-weight: 600;
  color: var(--muted);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
}

code {
  font-family: var(--mono);
  font-size: 0.86em;
  overflow-wrap: anywhere;
}
.fp, .hash {
  font-family: var(--mono);
  font-size: 0.78em;
  word-break: break-all;
}

.hash-box, .note-box {
  border: 1px solid var(--line);
  padding: 0.9rem 1rem;
  margin: 0.8rem 0 1.2rem;
  background: #fff;
}

.hash-box p { margin: 0.35rem 0; }

.placeholder {
  background: #f0f0f0;
  padding: 0 0.15em;
}

.dl-panel {
  margin: 1.4rem 0 1.8rem;
  padding: 1.3rem 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.dl-panel .btn { margin: 0.4rem 0 0.5rem; }

.specs {
  list-style: none;
  margin: 0 0 1rem;
  padding: 0;
  font-size: 0.92rem;
}

.specs li {
  display: flex;
  gap: 0.75rem;
  padding: 0.35rem 0;
  border-bottom: 0;
}

.specs .label {
  color: var(--muted);
  min-width: 6.2rem;
  flex-shrink: 0;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 1.6rem 0 2.4rem;
  color: var(--muted);
  font-size: 0.8rem;
}

.footer-inner {
  width: min(56rem, calc(100% - 2 * var(--pad)));
  margin-inline: auto;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1rem;
  margin-bottom: 0.7rem;
}

.footer-links a { color: var(--muted); text-decoration: none; }
.footer-links a:hover { color: var(--fg); }

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

.footer-copy { margin: 0.5rem 0 0; }

/* 404 */
.notfound {
  padding: 5rem 0 6rem;
  text-align: center;
}

.notfound h1 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 2rem;
  letter-spacing: 0.12em;
  margin: 0 0 0.8rem;
}

@media (max-width: 639px) {
  .page thead { display: none; }
  .page table, .page tbody, .page tr, .page th, .page td { display: block; width: 100%; }
  .page tr {
    border-bottom: 1px solid var(--line);
    padding: 0.9rem 0;
    margin: 0;
  }
  .page th, .page td {
    border-bottom: 0;
    padding: 0.15rem 0;
    width: 100%;
  }
  .page td:first-child {
    font-family: var(--mono);
    font-size: 0.82rem;
    width: 100%;
    padding-right: 0;
    padding-bottom: 0.35rem;
  }
}

/* Dark mode: follow system, still black-and-white */
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111111;
    --fg: #f3f3f3;
    --muted: #a3a3a3;
    --line: #2a2a2a;
    --btn: #f3f3f3;
    --btn-fg: #111111;
  }
  .hash-box, .note-box { background: #191919; }
  .placeholder { background: #2a2a2a; }
}

@media (min-width: 720px) {
  .hero { padding: 5rem 0 4rem; }
  .hero-icon { width: 112px; height: 112px; border-radius: 26px; }
  .hero h1 { font-size: 3rem; }
  .cta-row { flex-direction: row; justify-content: center; align-items: baseline; gap: 1rem; }
}

@media print {
  .site-header, .lang-btn, .cta-row, .btn { /* keep legal pages printable */ }
  .site-header .nav { display: none; }
}

@media (max-width: 400px) {
  .nav { gap: 0.1rem 0.7rem; font-size: 0.78rem; }
  .header-inner { gap: 0.5rem; }
}

code.nowrap { white-space: nowrap; overflow-wrap: normal; }

@media (prefers-color-scheme: dark) {
  .hero-icon,
  .brand img { box-shadow: 0 0 0 1px #3a3a3a; }
}


/* Changelog */
.log-item {
  margin: 0;
  padding: 1.5rem 0 0.4rem;
  border-top: 1px solid var(--line);
}
.log-item:first-of-type { border-top: 0; padding-top: 0.4rem; }
.log-item h2 {
  margin: 0 0 0.15rem;
  font-family: var(--serif);
  font-weight: 600;
  font-size: 1.2rem;
  letter-spacing: 0.06em;
}
.log-meta {
  margin: 0 0 0.7rem;
  color: var(--muted);
  font-size: 0.8rem;
}
.log-item ul { margin: 0.3rem 0 0.8rem; padding-left: 1.15rem; }
.log-item li { margin: 0.32rem 0; line-height: 1.65; }