:root {
  --ink: #07131f;
  --ink-2: #122536;
  --paper: #f3f6f8;
  --panel: #ffffff;
  --line: #d5dee6;
  --muted: #5b6b7a;
  --text: #1a2834;
  --accent: #0f8f86;
  --accent-2: #1470a8;
  --warn: #b45309;
  --shadow: 0 18px 50px rgba(7, 19, 31, .12);
  --radius: 2px;
  --font-sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-serif: "Noto Serif SC", "Songti SC", serif;
  --shell: min(1120px, calc(100% - 2.5rem));
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--text);
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(15, 143, 134, .08), transparent 55%),
    linear-gradient(180deg, #e9eef2 0%, var(--paper) 28%, var(--paper) 100%);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  min-height: 100vh;
}
img { max-width: 100%; display: block; }
a { color: var(--accent-2); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: var(--accent); }
.skip-link {
  position: absolute; left: -999px; top: 0; background: #000; color: #fff; padding: .5rem 1rem; z-index: 99;
}
.skip-link:focus { left: 1rem; top: 1rem; }

.dk-shell { width: var(--shell); margin-inline: auto; }

.dk-header {
  position: sticky; top: 0; z-index: 40;
  backdrop-filter: blur(12px);
  background: rgba(7, 19, 31, .88);
  border-bottom: 1px solid rgba(255,255,255,.06);
}
.dk-header__inner {
  display: flex; align-items: center; justify-content: space-between;
  min-height: 64px; gap: 1rem;
}
.dk-brand {
  display: inline-flex; align-items: center; gap: .7rem;
  color: #fff; text-decoration: none;
}
.dk-brand__mark {
  width: 34px; height: 34px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff; font-weight: 700; font-size: .78rem; letter-spacing: .04em;
}
.dk-brand__text {
  font-family: var(--font-serif);
  font-size: 1.15rem; font-weight: 700; letter-spacing: .04em;
}
.dk-brand__text span { color: #9fd8d3; font-weight: 600; margin-left: .15em; }
.dk-nav { display: flex; align-items: center; gap: 1.25rem; }
.dk-nav a {
  color: rgba(255,255,255,.78); text-decoration: none; font-size: .95rem;
  transition: color .2s ease;
}
.dk-nav a:hover, .dk-nav a.is-active { color: #fff; }
.dk-nav__search {
  padding: .35rem .8rem;
  border: 1px solid rgba(255,255,255,.22);
  color: #fff !important;
}
.dk-nav-toggle {
  display: none; width: 40px; height: 40px; border: 0; background: transparent; padding: 0;
}
.dk-nav-toggle span {
  display: block; width: 20px; height: 2px; margin: 5px auto; background: #fff;
}

.dk-hero {
  position: relative; overflow: hidden;
  background: linear-gradient(120deg, #0b1f33, #122536 55%, #0a2a2a);
  color: #fff;
}
.dk-hero__inner {
  position: relative; z-index: 1;
  padding: 2.25rem 0 2rem;
}
.dk-hero__brand {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 3vw, 2rem);
  line-height: 1.2; margin: 0 0 .45rem;
  letter-spacing: .02em;
}
.dk-hero__lead {
  max-width: 36rem; margin: 0 0 1rem;
  color: rgba(255,255,255,.72); font-size: .98rem;
}
.dk-search {
  display: flex; max-width: 560px; background: rgba(255,255,255,.08);
  border: 1px solid rgba(255,255,255,.18); backdrop-filter: blur(8px);
}
.dk-search input {
  flex: 1; border: 0; background: transparent; color: #fff;
  padding: .95rem 1rem; font: inherit; outline: none;
}
.dk-search input::placeholder { color: rgba(255,255,255,.45); }
.dk-search button {
  border: 0; background: var(--accent); color: #fff;
  padding: 0 1.25rem; font: inherit; cursor: pointer;
}
.dk-search button:hover { background: #0c7a73; }

.dk-section { padding: 3.5rem 0; }
.dk-section--tight { padding: 2.25rem 0 3.5rem; }
.dk-kicker {
  color: var(--accent); font-size: .8rem; letter-spacing: .16em;
  text-transform: uppercase; margin: 0 0 .55rem; font-weight: 700;
}
.dk-h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  margin: 0 0 .4rem; line-height: 1.25;
}
.dk-lead { color: var(--muted); margin: 0 0 1.75rem; max-width: 40rem; }

.dk-cats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px; background: var(--line);
  border: 1px solid var(--line);
}
.dk-cat {
  background: var(--panel); padding: 1.35rem 1.2rem;
  text-decoration: none; color: inherit;
  transition: background .2s ease, transform .25s ease;
}
.dk-cat:hover { background: #eef8f7; transform: translateY(-2px); }
.dk-cat strong {
  display: block; font-family: var(--font-serif); font-size: 1.15rem; margin-bottom: .35rem;
}
.dk-cat span { color: var(--muted); font-size: .92rem; }
.dk-cat em {
  display: inline-block; margin-top: .85rem;
  font-style: normal; color: var(--accent); font-size: .85rem; font-weight: 600;
}

.dk-list { display: grid; gap: 0; }
.dk-item {
  display: grid; gap: .45rem;
  padding: 1.35rem 0;
  border-bottom: 1px solid var(--line);
  text-decoration: none; color: inherit;
}
.dk-item:first-child { border-top: 1px solid var(--line); }
.dk-item:hover .dk-item__title { color: var(--accent-2); }
.dk-item__title {
  margin: 0; font-family: var(--font-serif); font-size: 1.2rem; line-height: 1.35;
  transition: color .2s ease;
}
.dk-item__sum { margin: 0; color: var(--muted); }
.dk-meta {
  display: flex; flex-wrap: wrap; gap: .75rem 1rem;
  color: var(--muted); font-size: .85rem;
}
.dk-meta b {
  font-weight: 600; color: var(--accent);
}

.dk-banner {
  background: linear-gradient(120deg, var(--ink), var(--ink-2));
  color: #fff; padding: 3rem 0 2.4rem;
}
.dk-banner h1 {
  font-family: var(--font-serif);
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  margin: 0 0 .5rem;
}
.dk-banner p { margin: 0; color: rgba(255,255,255,.72); }

.dk-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 260px;
  gap: 2.5rem;
  align-items: start;
}
.dk-side {
  position: sticky; top: 88px;
  background: var(--panel);
  border: 1px solid var(--line);
  padding: 1.1rem;
}
.dk-side h3 {
  margin: 0 0 .8rem; font-size: .95rem; letter-spacing: .04em;
}
.dk-filters { display: grid; gap: .35rem; }
.dk-filters a {
  display: flex; justify-content: space-between; gap: .5rem;
  padding: .55rem .65rem; text-decoration: none; color: var(--text);
  border-left: 2px solid transparent;
}
.dk-filters a:hover, .dk-filters a.is-active {
  background: #eef8f7; border-left-color: var(--accent); color: var(--ink);
}
.dk-filters a span { color: var(--muted); font-size: .85rem; }

.dk-pager {
  display: flex; flex-wrap: wrap; gap: .4rem; margin-top: 1.75rem;
}
.dk-pager a, .dk-pager span {
  min-width: 2.2rem; height: 2.2rem; display: grid; place-items: center;
  border: 1px solid var(--line); background: var(--panel);
  text-decoration: none; color: var(--text); font-size: .9rem;
}
.dk-pager a:hover { border-color: var(--accent); color: var(--accent); }
.dk-pager .is-current {
  background: var(--ink); color: #fff; border-color: var(--ink);
}

.dk-article {
  background: var(--panel);
  border: 1px solid var(--line);
  padding: clamp(1.4rem, 3vw, 2.4rem);
  box-shadow: var(--shadow);
}
.dk-article__title {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 3.4vw, 2.35rem);
  line-height: 1.25; margin: 0 0 .8rem;
}
.dk-summary {
  margin: 1.4rem 0;
  padding: 1rem 1.1rem;
  background: #eef6f8;
  border-left: 3px solid var(--accent);
}
.dk-summary h2 { margin: 0 0 .4rem; font-size: 1rem; }
.dk-summary p { margin: 0; color: var(--muted); }
.dk-content {
  font-size: 1.02rem;
}
.dk-content h1, .dk-content h2, .dk-content h3 {
  font-family: var(--font-serif);
  line-height: 1.3;
  margin: 1.6em 0 .6em;
}
.dk-content p { margin: 0 0 1em; }
.dk-content ul, .dk-content ol { padding-left: 1.3rem; }
.dk-content img { margin: 1rem 0; }
.dk-article__foot {
  margin-top: 2rem; padding-top: 1.2rem;
  border-top: 1px solid var(--line);
  display: grid; gap: 1rem;
}
.dk-disclaimer {
  color: var(--muted); font-size: .88rem; margin: 0;
}

.dk-empty {
  padding: 2.5rem 1rem; text-align: center; color: var(--muted);
  border: 1px dashed var(--line); background: rgba(255,255,255,.6);
}

.dk-stats {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px;
  background: var(--line); border: 1px solid var(--line); margin-bottom: 2rem;
}
.dk-stat {
  background: var(--panel); padding: 1.2rem; text-align: center;
}
.dk-stat strong {
  display: block; font-family: var(--font-serif); font-size: 1.8rem; color: var(--ink);
}
.dk-stat span { color: var(--muted); font-size: .9rem; }
.dk-about-block {
  max-width: 760px; margin-bottom: 2rem;
}
.dk-about-block h2 {
  font-family: var(--font-serif); font-size: 1.35rem; margin: 0 0 .85rem;
}
.dk-about-block p {
  margin: 0 0 .85rem; color: var(--muted); line-height: 1.75;
}
.dk-about-block ul {
  margin: 0 0 1rem; padding-left: 1.25rem; color: var(--muted);
}
.dk-about-block li { margin-bottom: .35rem; }
.dk-feedback {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: .9rem 1rem;
  margin-top: 1rem;
  max-width: 640px;
}
.dk-feedback label {
  display: grid; gap: .35rem; font-size: .9rem; color: var(--text);
}
.dk-feedback .span-2 { grid-column: 1 / -1; }
.dk-feedback .req { color: #b42318; margin-left: 2px; }
.dk-feedback input,
.dk-feedback textarea {
  width: 100%; border: 1px solid var(--line); background: #fff;
  padding: .7rem .8rem; font: inherit; color: var(--text); outline: none;
}
.dk-feedback input:focus,
.dk-feedback textarea:focus { border-color: var(--accent); }
.dk-feedback-turnstile { min-height: 65px; }
.dk-feedback-actions {
  display: flex; flex-wrap: wrap; align-items: center; gap: .85rem;
}
.dk-feedback-actions button {
  border: 0; background: var(--ink); color: #fff;
  padding: .75rem 1.25rem; font: inherit; cursor: pointer;
}
.dk-feedback-actions button:hover { background: var(--ink-2); }
.dk-feedback-actions button:disabled { opacity: .6; cursor: wait; }
.dk-feedback-msg { margin: 0; color: var(--muted); font-size: .92rem; }
.dk-feedback-msg.is-ok { color: var(--accent); }
.dk-feedback-msg.is-err { color: #b42318; }

.dk-about-features {
  display: grid; grid-template-columns: repeat(2, 1fr); gap: 1px;
  background: var(--line); border: 1px solid var(--line);
}
.dk-about-feature {
  background: var(--panel); padding: 1.25rem 1.2rem;
}
.dk-about-feature h3 {
  margin: 0 0 .45rem; font-family: var(--font-serif); font-size: 1.05rem;
}
.dk-about-feature p { margin: 0; color: var(--muted); font-size: .95rem; }

.dk-footer {
  margin-top: 3rem;
  background: var(--ink);
  color: rgba(255,255,255,.72);
  padding: 2.4rem 0 2rem;
}
.dk-footer a { color: rgba(255,255,255,.82); text-decoration: none; }
.dk-footer a:hover { color: #fff; }
.dk-footer__inner { display: grid; gap: 1.2rem; }
.dk-footer__brand strong {
  display: block; color: #fff; font-family: var(--font-serif);
  font-size: 1.15rem; margin-bottom: .35rem;
}
.dk-footer__brand p { margin: 0; max-width: 28rem; }
.dk-footer__nav { display: flex; flex-wrap: wrap; gap: .85rem 1.25rem; }
.dk-footer__copy { margin: 0; font-size: .85rem; color: rgba(255,255,255,.45); }

[data-reveal] {
  opacity: 0; transform: translateY(14px);
  transition: opacity .55s ease var(--delay, 0ms), transform .55s ease var(--delay, 0ms);
}
[data-reveal].is-in { opacity: 1; transform: none; }

@media (max-width: 900px) {
  .dk-cats { grid-template-columns: 1fr 1fr; }
  .dk-layout { grid-template-columns: 1fr; }
  .dk-side { position: static; }
  .dk-stats { grid-template-columns: 1fr 1fr; }
  .dk-about-features { grid-template-columns: 1fr; }
  .dk-feedback { grid-template-columns: 1fr; }
}
@media (max-width: 720px) {
  :root { --shell: min(100% - 1.5rem, 1120px); }
  .dk-nav-toggle { display: block; }
  .dk-nav {
    display: none; position: absolute; left: 0; right: 0; top: 64px;
    background: var(--ink); flex-direction: column; align-items: stretch;
    padding: 1rem 1.25rem 1.25rem; gap: .85rem;
    border-bottom: 1px solid rgba(255,255,255,.08);
  }
  .dk-nav.is-open { display: flex; }
  .dk-cats { grid-template-columns: 1fr; }
  .dk-hero__inner { padding: 1.75rem 0 1.5rem; }
}