/* ==========================================================================
   ZRdb · design system  (2026-10)
   纯 CSS，无外部字体/CDN；叠在 Bootstrap 5.0.2 之上做视觉层
   ========================================================================== */

:root {
  --ink:        #0f231d;
  --ink-2:      #33473f;
  --muted:      #6c7c74;
  --line:       #e3e8e3;
  --line-soft:  #eef1ee;
  --paper:      #ffffff;
  --sand:       #f6f7f4;
  --sand-2:     #eff2ec;
  --jade:       #1c7a5b;
  --jade-2:     #2f9e79;
  --jade-soft:  #e8f3ee;
  --deep:       #08201a;
  --deep-2:     #0f2f26;
  --amber:      #b4690e;

  --radius:     14px;
  --radius-sm:  9px;
  --shadow:     0 1px 2px rgba(15,35,29,.04), 0 8px 24px -12px rgba(15,35,29,.18);
  --shadow-lg:  0 24px 60px -30px rgba(8,32,26,.45);

  --font-ui: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue",
             Arial, "Noto Sans", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-display: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua",
                  Georgia, "Songti SC", serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  --shell: 1160px;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-ui);
  font-size: 16px;
  line-height: 1.65;
  color: var(--ink-2);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* ---------- 通用排版 ---------- */

.zk-shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: 24px;
}

.zk-kicker {
  display: inline-block;
  font-size: .72rem;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--jade);
  margin-bottom: 14px;
}

.zk-h1 {
  font-family: var(--font-display);
  font-size: clamp(2.3rem, 4.4vw, 3.5rem);
  line-height: 1.1;
  letter-spacing: -.015em;
  color: var(--ink);
  margin: 0 0 18px;
  font-weight: 600;
  text-wrap: balance;
}

.zk-h2 {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 2.4vw, 2rem);
  line-height: 1.2;
  letter-spacing: -.01em;
  color: var(--ink);
  margin: 0 0 14px;
  font-weight: 600;
}

.zk-h3 {
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: .01em;
  color: var(--ink);
  margin: 0 0 8px;
}

.zk-lede {
  font-size: 1.06rem;
  line-height: 1.7;
  color: var(--ink-2);
  max-width: 62ch;
}

.zk-muted { color: var(--muted); }
.zk-mono { font-family: var(--font-mono); font-size: .92em; }

a { color: var(--jade); text-decoration: none; }
a:hover { color: var(--jade-2); text-decoration: underline; text-underline-offset: 2px; }

/* ---------- 顶部导航 ---------- */

.zk-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,.86);
  backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--line);
}

.zk-header__inner {
  display: flex;
  align-items: center;
  gap: 28px;
  min-height: 66px;
}

.zk-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  flex: 0 0 auto;
}
.zk-brand:hover { text-decoration: none; }

.zk-brand__mark {
  height: 32px;
  width: 32px;
  display: block;
  flex: 0 0 auto;
}

.zk-brand__text { display: flex; flex-direction: column; line-height: 1.15; }

.zk-brand__name {
  font-family: var(--font-display);
  font-size: 1.22rem;
  font-weight: 700;
  letter-spacing: -.01em;
  color: var(--ink);
}

.zk-brand__sub {
  font-size: .68rem;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--muted);
}

.zk-nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 4px;
  flex-wrap: wrap;
}

.zk-nav__link {
  padding: 8px 14px;
  border-radius: 999px;
  font-size: .92rem;
  font-weight: 500;
  color: var(--ink-2);
  white-space: nowrap;
  transition: background .16s ease, color .16s ease;
}
.zk-nav__link:hover { background: var(--sand-2); color: var(--ink); text-decoration: none; }
.zk-nav__link.is-active { background: var(--ink); color: #fff; }
.zk-nav__link.is-active:hover { background: var(--ink); color: #fff; }

/* ---------- Hero ---------- */

.zk-hero {
  position: relative;
  color: #fff;
  background:
    radial-gradient(1200px 380px at 78% -10%, rgba(47,158,121,.34), transparent 62%),
    linear-gradient(160deg, var(--deep) 0%, var(--deep-2) 55%, #0a2a22 100%);
  overflow: hidden;
  isolation: isolate;
}

.zk-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: url("/static/ele/Tree-web.jpg");
  background-position: center 38%;
  background-size: cover;
  opacity: .16;
  mix-blend-mode: luminosity;
  z-index: -1;
}

.zk-hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 140px;
  background: linear-gradient(to bottom, transparent, rgba(8,32,26,.85));
  z-index: -1;
}

.zk-hero__inner {
  padding: clamp(64px, 9vw, 116px) 24px clamp(56px, 7vw, 88px);
  max-width: var(--shell);
  margin-inline: auto;
}

.zk-hero .zk-kicker { color: #8fd7b8; }

.zk-hero__title {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 5vw, 3.9rem);
  line-height: 1.05;
  letter-spacing: -.02em;
  font-weight: 600;
  color: #fff;
  margin: 0 0 22px;
  max-width: 20ch;
  text-wrap: balance;
}
.zk-hero__title em {
  font-style: italic;
  color: #a9e3c9;
}

.zk-hero__lede {
  font-size: 1.06rem;
  line-height: 1.7;
  color: rgba(255,255,255,.78);
  max-width: 54ch;
  margin: 0 0 34px;
}

/* 搜索条 */
.zk-search {
  display: flex;
  gap: 10px;
  align-items: stretch;
  max-width: 660px;
  background: #fff;
  border-radius: 999px;
  padding: 8px 8px 8px 22px;
  box-shadow: var(--shadow-lg);
}

.zk-search input[type="text"] {
  flex: 1 1 auto;
  min-width: 0;
  border: 0;
  outline: 0;
  font-family: var(--font-ui);
  font-size: 1rem;
  color: var(--ink);
  background: transparent;
  padding: 12px 4px;
}
.zk-search input::placeholder { color: #9aa8a1; }

.zk-search button {
  flex: 0 0 auto;
  border: 0;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  font-size: .95rem;
  font-weight: 600;
  padding: 12px 26px;
  cursor: pointer;
  transition: background .16s ease, transform .16s ease;
}
.zk-search button:hover { background: var(--jade); }

.zk-hints {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-top: 20px;
  font-size: .85rem;
  color: rgba(255,255,255,.6);
}

.zk-chip {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,.22);
  background: rgba(255,255,255,.06);
  color: rgba(255,255,255,.86);
  font-family: var(--font-mono);
  font-size: .8rem;
  transition: background .16s ease, border-color .16s ease;
}
.zk-chip:hover {
  background: rgba(255,255,255,.14);
  border-color: rgba(255,255,255,.4);
  color: #fff;
  text-decoration: none;
}

/* ---------- 内容区 ---------- */

.zk-section { padding: clamp(56px, 7vw, 92px) 0; }
.zk-section--sand { background: var(--sand); border-block: 1px solid var(--line); }

.zk-split {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
  gap: clamp(28px, 4vw, 64px);
  align-items: start;
}

.zk-prose { max-width: 68ch; }
.zk-prose p { margin: 0 0 1.05em; }
.zk-prose p:last-child { margin-bottom: 0; }

.zk-card {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(20px, 2.6vw, 30px);
  box-shadow: var(--shadow);
}

.zk-card--flush { padding: 0; overflow: hidden; }

.zk-card__label {
  font-size: .7rem;
  letter-spacing: .13em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 12px;
}

/* 数据源清单 */
.zk-sources { list-style: none; margin: 0; padding: 0; }
.zk-sources li {
  display: flex;
  gap: 12px;
  padding: 11px 0;
  border-bottom: 1px solid var(--line-soft);
  font-size: .94rem;
}
.zk-sources li:last-child { border-bottom: 0; }
.zk-sources b {
  flex: 0 0 88px;
  font-weight: 600;
  color: var(--ink);
}
.zk-sources span { color: var(--muted); }

/* 特性三栏 */
.zk-features {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.zk-feature {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 24px;
  border-top: 3px solid var(--jade);
}
.zk-feature h3 {
  font-size: .98rem;
  font-weight: 700;
  color: var(--ink);
  margin: 0 0 8px;
}
.zk-feature p { margin: 0; font-size: .92rem; color: var(--muted); line-height: 1.6; }

/* ---------- 内页页头 ---------- */

.zk-pagehead {
  background: var(--sand);
  border-bottom: 1px solid var(--line);
}
.zk-pagehead__inner {
  padding: clamp(40px, 5vw, 64px) 24px clamp(34px, 4vw, 52px);
  max-width: var(--shell);
  margin-inline: auto;
}
.zk-pagehead .zk-h1 { margin-bottom: 10px; }
.zk-pagehead .zk-lede { color: var(--muted); }

/* ---------- 搜索页 ---------- */

.zk-seg {
  display: inline-flex;
  gap: 4px;
  padding: 5px;
  background: var(--sand-2);
  border-radius: 999px;
  border: 1px solid var(--line);
  margin-bottom: 26px;
  flex-wrap: wrap;
}

.zk-seg .nav-link {
  border: 0;
  background: transparent;
  border-radius: 999px;
  padding: 9px 20px;
  font-size: .92rem;
  font-weight: 600;
  color: var(--ink-2);
  cursor: pointer;
}
.zk-seg .nav-link:hover { color: var(--ink); }
.zk-seg .nav-link.active {
  background: var(--paper);
  color: var(--ink);
  box-shadow: 0 1px 3px rgba(15,35,29,.12);
}

.zk-form { max-width: 680px; }
.zk-form .form-control {
  flex: 1 1 260px;
  width: auto;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  padding: 14px 16px;
  font-size: 1rem;
  color: var(--ink);
  background: var(--paper);
}
.zk-form .form-control:focus {
  border-color: var(--jade-2);
  box-shadow: 0 0 0 4px var(--jade-soft);
}

.zk-btn {
  display: inline-block;
  border: 0;
  border-radius: var(--radius-sm);
  background: var(--ink);
  color: #fff !important;
  font-weight: 600;
  font-size: .95rem;
  padding: 13px 26px;
  cursor: pointer;
  text-decoration: none;
  transition: background .16s ease;
}
.zk-btn:hover { background: var(--jade); text-decoration: none; }

.zk-btn--ghost {
  background: transparent;
  color: var(--ink) !important;
  border: 1px solid var(--line);
}
.zk-btn--ghost:hover { background: var(--sand-2); border-color: var(--line); }

.zk-field-label {
  display: block;
  font-size: .92rem;
  color: var(--muted);
  margin-bottom: 10px;
}

.zk-examples {
  margin-top: 22px;
  font-size: .88rem;
  color: var(--muted);
}
.zk-examples code {
  font-family: var(--font-mono);
  background: var(--sand-2);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 2px 7px;
  margin-right: 6px;
  color: var(--ink-2);
}

/* ---------- 帮助 / 文档 ---------- */

.zk-doc { max-width: 78ch; }
.zk-doc h2 {
  font-family: var(--font-display);
  font-size: 1.55rem;
  color: var(--ink);
  margin: 0 0 18px;
  font-weight: 600;
  letter-spacing: -.01em;
}
.zk-doc h3 {
  font-size: 1.02rem;
  font-weight: 700;
  color: var(--ink);
  margin: 30px 0 8px;
}
.zk-doc p { margin: 0 0 1em; color: var(--ink-2); }
.zk-doc .zk-card + .zk-card { margin-top: 22px; }
.zk-doc dl { margin: 0; }
.zk-doc dt {
  font-weight: 700;
  color: var(--ink);
  margin-top: 18px;
  font-size: .98rem;
}
.zk-doc dd {
  margin: 4px 0 0;
  color: var(--ink-2);
  font-size: .96rem;
}

/* ---------- 图（Overview） ---------- */

.zk-figure {
  margin: 0;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: var(--shadow);
}
.zk-figure img { display: block; width: 100%; height: auto; border-radius: 8px; }
.zk-figure figcaption {
  margin-top: 14px;
  font-size: .86rem;
  color: var(--muted);
  line-height: 1.6;
}
.zk-figure figcaption b { color: var(--ink-2); }

.img-magnifier-container { position: relative; }
.img-magnifier-glass {
  position: absolute;
  border: 2px solid var(--jade);
  border-radius: 50%;
  cursor: none;
  width: 110px;
  height: 110px;
  box-shadow: 0 6px 20px rgba(8,32,26,.28);
  pointer-events: none;
}

/* ---------- 联系页 ---------- */

.zk-contact {
  display: grid;
  grid-template-columns: minmax(0, .95fr) minmax(0, 1.05fr);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--paper);
  box-shadow: var(--shadow);
}
.zk-contact__media { min-height: 100%; }
.zk-contact__media img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
  min-height: 280px;
}
.zk-contact__body { padding: clamp(24px, 3.4vw, 44px); }
.zk-contact__body .zk-h2 { font-size: 1.5rem; }
.zk-contact__body p { color: var(--ink-2); margin: 0 0 18px; }

.zk-mail {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-family: var(--font-mono);
  font-size: .95rem;
  color: var(--ink);
  background: var(--sand);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 10px 18px;
  text-decoration: none;
}
.zk-mail:hover { border-color: var(--jade-2); background: var(--jade-soft); text-decoration: none; color: var(--ink); }
.zk-mail::before {
  content: "";
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--jade-2);
}

/* ---------- 页脚 ---------- */

.zk-footer {
  background: var(--deep);
  color: rgba(255,255,255,.7);
  margin-top: 0;
}
.zk-footer a { color: rgba(255,255,255,.86); }
.zk-footer a:hover { color: #fff; }

.zk-footer__grid {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1.2fr;
  gap: clamp(24px, 4vw, 56px);
  padding: clamp(44px, 5vw, 64px) 0 40px;
}

.zk-footer .zk-brand__name { color: #fff; }
.zk-footer .zk-brand__sub { color: rgba(255,255,255,.5); }
.zk-footer__tagline { margin: 14px 0 0; font-size: .9rem; line-height: 1.7; max-width: 34ch; }

.zk-footer h4 {
  font-size: .72rem;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: rgba(255,255,255,.45);
  margin: 0 0 14px;
  font-weight: 600;
}
.zk-footer ul { list-style: none; margin: 0; padding: 0; }
.zk-footer li { margin-bottom: 9px; font-size: .92rem; }

.zk-footer__bar {
  border-top: 1px solid rgba(255,255,255,.1);
  padding: 18px 0 24px;
  font-size: .82rem;
  color: rgba(255,255,255,.45);
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: space-between;
}

/* ---------- 响应式 ---------- */

@media (max-width: 900px) {
  .zk-split { grid-template-columns: 1fr; }
  .zk-features { grid-template-columns: 1fr; }
  .zk-contact { grid-template-columns: 1fr; }
  .zk-footer__grid { grid-template-columns: 1fr 1fr; }
  .zk-footer__grid > :first-child { grid-column: 1 / -1; }
}

@media (max-width: 720px) {
  .zk-header__inner { min-height: auto; padding-block: 10px; gap: 12px; flex-wrap: wrap; }
  .zk-nav { margin-left: 0; width: 100%; overflow-x: auto; padding-bottom: 4px; }
  .zk-nav__link { padding: 7px 12px; font-size: .88rem; }
  .zk-hero__inner { padding-top: 52px; }
  .zk-search { flex-direction: column; border-radius: 22px; padding: 10px; }
  .zk-search input[type="text"] { padding: 10px 8px; }
  .zk-search button { width: 100%; }
  .zk-footer__grid { grid-template-columns: 1fr; }
}

/* 焦点可见性 */
:focus-visible {
  outline: 2px solid var(--jade-2);
  outline-offset: 2px;
  border-radius: 6px;
}

/* 兼容旧页面残留的 .bg / .bg2 占位块 */
.bg2:empty, .bg:empty { display: none; }

/* /browse/ 索引页 (后端保留了干净 URL + 动态 sitemap, 因此这一页也得能看) */
.zk-count {
  font-size: .8rem;
  font-weight: 600;
  color: #6c7c74;
  background: #eff2ec;
  border: 1px solid #e3e8e3;
  border-radius: 999px;
  padding: 3px 10px;
  vertical-align: middle;
  margin-left: 8px;
}
.zk-chiplist { display: flex; flex-wrap: wrap; gap: 8px; }
.zk-chiplist__item {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: .82rem;
  color: #33473f;
  background: #fff;
  border: 1px solid #e3e8e3;
  border-radius: 8px;
  padding: 5px 10px;
  text-decoration: none;
}
.zk-chiplist__item:hover { background: #e8f3ee; border-color: #2f9e79; color: #0f231d; text-decoration: none; }