/* ==========================================================================
   牛牛棋牌 /assets/site.css — 共享外观层
   1 重置与令牌  2 基础排版  3 版式骨架  4 通用组件
   5 页头  6 页脚  7 工具类  8 响应式  9 动效降级
   ========================================================================== */

/* 1. 重置与令牌 ------------------------------------------------------------ */
*,
*::before,
*::after { box-sizing: border-box; }

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

body,
h1, h2, h3, h4, h5, h6,
p, ul, ol, li, dl, dt, dd, figure, blockquote, fieldset {
  margin: 0;
  padding: 0;
}

ul, ol { list-style: none; }

img, svg, video, canvas {
  display: block;
  max-width: 100%;
}

button, input, select, textarea {
  font: inherit;
  color: inherit;
}

button { background: none; border: 0; }

a { color: inherit; text-decoration: none; }

table { border-collapse: collapse; width: 100%; }

[hidden] { display: none !important; }

:root {
  --nn-green: #0B3B2E;
  --nn-green-deep: #06261D;
  --nn-green-soft: #0F4A38;
  --nn-gold: #B08D57;
  --nn-gold-soft: #D4B88C;
  --nn-gold-mute: #8A734E;
  --nn-red: #C0392B;
  --nn-red-bright: #E74C3C;
  --nn-paper: #F5F0E6;
  --nn-ink: #1C1C1C;

  --nn-font-display: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", Georgia, "Times New Roman", serif;
  --nn-font-body: "Inter", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --nn-font-index: "Inter", "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;

  --nn-container: 1260px;
  --nn-gutter: clamp(1.25rem, 4vw, 3.5rem);
  --nn-header-h: 78px;
  --nn-cut: 20px;

  --nn-hairline: rgba(176, 141, 87, 0.30);
  --nn-hairline-soft: rgba(176, 141, 87, 0.16);
  --nn-paper-ink: rgba(28, 28, 28, 0.76);
  --nn-dark-ink: rgba(245, 240, 230, 0.72);

  --nn-ease: cubic-bezier(0.2, 0.6, 0.3, 1);
  --nn-shadow: 0 30px 70px -40px rgba(0, 0, 0, 0.9);
}

/* 2. 基础排版 -------------------------------------------------------------- */
body {
  min-height: 100vh;
  background-color: var(--nn-green);
  color: var(--nn-paper);
  font-family: var(--nn-font-body);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.75;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

::selection {
  background: var(--nn-gold);
  color: var(--nn-green-deep);
}

:focus-visible {
  outline: 2px solid var(--nn-gold-soft);
  outline-offset: 3px;
}

p { line-height: 1.85; }
strong { font-weight: 600; }

.nn-display {
  font-family: var(--nn-font-display);
  font-weight: 300;
  font-size: clamp(2.6rem, 8.5vw, 6.5rem);
  line-height: 0.98;
  letter-spacing: -0.01em;
}

.nn-h1 {
  font-family: var(--nn-font-display);
  font-weight: 400;
  font-size: clamp(2rem, 5vw, 3.6rem);
  line-height: 1.15;
  letter-spacing: 0.01em;
}

.nn-h2 {
  font-family: var(--nn-font-display);
  font-weight: 400;
  font-size: clamp(1.5rem, 3.4vw, 2.4rem);
  line-height: 1.25;
}

.nn-h3 {
  font-family: var(--nn-font-display);
  font-weight: 400;
  font-size: clamp(1.08rem, 2vw, 1.38rem);
  line-height: 1.45;
}

.nn-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  font-family: var(--nn-font-index);
  font-size: 0.66rem;
  font-weight: 400;
  letter-spacing: 0.34em;
  text-transform: uppercase;
  color: var(--nn-gold-mute);
}

.nn-kicker::before {
  content: "";
  width: 2.2rem;
  height: 1px;
  background: currentColor;
  opacity: 0.7;
}

.nn-index {
  font-family: var(--nn-font-index);
  font-size: 0.66rem;
  font-weight: 400;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--nn-gold-mute);
}

.nn-lede {
  max-width: 62ch;
  font-size: clamp(1.02rem, 1.6vw, 1.24rem);
  line-height: 1.9;
  color: var(--nn-dark-ink);
}

.nn-numeral {
  font-family: var(--nn-font-display);
  font-weight: 300;
  font-size: clamp(3rem, 10vw, 7rem);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--nn-gold);
}

.nn-prose {
  max-width: 70ch;
  font-size: 1rem;
  line-height: 1.95;
}

.nn-prose p + p { margin-top: 1.1em; }

.nn-prose h2 {
  margin: 2.2em 0 0.6em;
  font-family: var(--nn-font-display);
  font-size: 1.5rem;
  font-weight: 400;
  line-height: 1.35;
}

.nn-prose h3 {
  margin: 1.8em 0 0.5em;
  font-family: var(--nn-font-display);
  font-size: 1.15rem;
  font-weight: 400;
}

.nn-prose ul { margin-top: 1em; }

.nn-prose li {
  position: relative;
  padding-left: 1.25rem;
  margin-top: 0.5em;
}

.nn-prose li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.78em;
  width: 0.55rem;
  height: 1px;
  background: var(--nn-gold);
}

.nn-prose strong { color: var(--nn-gold-soft); }

.nn-rule {
  height: 1px;
  border: 0;
  background: var(--nn-hairline);
}

.nn-slash-wrap { overflow: hidden; }

.nn-slash {
  display: block;
  width: 108%;
  height: 1px;
  margin-left: -4%;
  background: linear-gradient(90deg, transparent, var(--nn-gold-mute), transparent);
  transform: rotate(-2.2deg);
  transform-origin: center;
  opacity: 0.65;
}

.nn-stamp {
  display: inline-block;
  padding: 0.28rem 0.62rem;
  font-family: var(--nn-font-display);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  color: var(--nn-red-bright);
  border: 1px solid var(--nn-red);
  background: rgba(192, 57, 43, 0.08);
  transform: rotate(-3deg);
}

/* 3. 版式骨架 -------------------------------------------------------------- */
.nn-container {
  width: 100%;
  max-width: var(--nn-container);
  margin-inline: auto;
  padding-inline: var(--nn-gutter);
}

.nn-container--narrow { max-width: 820px; }
.nn-container--wide { max-width: 1520px; }

#main-content {
  display: block;
  scroll-margin-top: calc(var(--nn-header-h) + 1rem);
}

.nn-section {
  position: relative;
  padding-block: clamp(3rem, 7vw, 6rem);
}

.nn-section--tight { padding-block: clamp(2rem, 4vw, 3rem); }
.nn-section--paper { background: var(--nn-paper); color: var(--nn-ink); }
.nn-section--deep { background: var(--nn-green-deep); }
.nn-section--green { background: var(--nn-green); }

.nn-section--veil {
  background: linear-gradient(165deg, var(--nn-green) 0%, var(--nn-green-deep) 55%, #072b21 100%);
}

.nn-section--paper .nn-lede { color: var(--nn-paper-ink); }
.nn-section--paper .nn-panel__body { color: var(--nn-paper-ink); }
.nn-section--paper .nn-fold__body { color: var(--nn-paper-ink); }
.nn-section--paper .nn-log__text { color: var(--nn-paper-ink); }
.nn-section--paper .nn-prose strong { color: var(--nn-red); }
.nn-section--paper .nn-numeral { color: var(--nn-gold-mute); }

.nn-page-head {
  position: relative;
  overflow: hidden;
  padding-top: calc(var(--nn-header-h) + clamp(2.25rem, 6vw, 4.5rem));
  padding-bottom: clamp(1.75rem, 4vw, 3rem);
  background: linear-gradient(160deg, var(--nn-green) 0%, var(--nn-green-deep) 72%);
}

.nn-page-head::after {
  content: "";
  position: absolute;
  left: -5%;
  right: -5%;
  bottom: -2px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--nn-gold), transparent);
  transform: rotate(-0.8deg);
  opacity: 0.7;
  pointer-events: none;
}

.nn-breadcrumb { padding-block: 0.5rem; }

.nn-breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.2rem 0.5rem;
  font-family: var(--nn-font-index);
  font-size: 0.66rem;
  letter-spacing: 0.18em;
  color: var(--nn-gold-mute);
}

.nn-breadcrumb__item {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.nn-breadcrumb__item:not(:first-child)::before {
  content: "/";
  opacity: 0.55;
}

.nn-breadcrumb__link { color: var(--nn-gold-soft); }
.nn-breadcrumb__link:hover { color: var(--nn-paper); }

.nn-grid {
  display: grid;
  gap: clamp(1rem, 2.4vw, 2rem);
}

.nn-grid--2 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 320px), 1fr)); }
.nn-grid--3 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 264px), 1fr)); }
.nn-grid--4 { grid-template-columns: repeat(auto-fit, minmax(min(100%, 200px), 1fr)); }

.nn-grid--index {
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 210px), 1fr));
  gap: 0;
}

/* 4. 通用组件 -------------------------------------------------------------- */
.nn-btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.78rem 1.6rem;
  font-family: var(--nn-font-index);
  font-size: 0.82rem;
  letter-spacing: 0.18em;
  color: var(--nn-gold-soft);
  background: transparent;
  border: 1px solid var(--nn-gold-mute);
  cursor: pointer;
  clip-path: polygon(
    var(--nn-cut) 0,
    100% 0,
    100% calc(100% - var(--nn-cut)),
    calc(100% - var(--nn-cut)) 100%,
    0 100%,
    0 var(--nn-cut)
  );
  transition: background-color 0.3s var(--nn-ease), color 0.3s var(--nn-ease),
    border-color 0.3s var(--nn-ease), transform 0.3s var(--nn-ease);
}

.nn-btn:hover {
  color: var(--nn-paper);
  border-color: var(--nn-gold);
  background: rgba(176, 141, 87, 0.16);
  transform: translateY(-1px);
}

.nn-btn--gold {
  background: var(--nn-gold);
  border-color: var(--nn-gold);
  color: var(--nn-green-deep);
}

.nn-btn--gold:hover {
  background: var(--nn-gold-soft);
  border-color: var(--nn-gold-soft);
  color: var(--nn-green-deep);
}

.nn-btn--block {
  width: 100%;
}

.nn-link {
  color: var(--nn-gold-soft);
  border-bottom: 1px solid var(--nn-hairline);
  padding-bottom: 1px;
  transition: color 0.25s var(--nn-ease), border-color 0.25s var(--nn-ease);
}

.nn-link:hover {
  color: var(--nn-paper);
  border-color: var(--nn-gold);
}

.nn-chip {
  display: inline-flex;
  align-items: center;
  padding: 0.42rem 0.9rem;
  font-family: var(--nn-font-index);
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  color: var(--nn-gold-soft);
  background: transparent;
  border: 1px solid var(--nn-hairline);
  cursor: pointer;
  transition: background-color 0.25s var(--nn-ease), color 0.25s var(--nn-ease),
    border-color 0.25s var(--nn-ease);
}

.nn-chip:hover {
  color: var(--nn-paper);
  border-color: var(--nn-gold);
}

.nn-chip[aria-pressed="true"] {
  background: var(--nn-gold);
  border-color: var(--nn-gold);
  color: var(--nn-green-deep);
}

.nn-filterbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.nn-section--paper .nn-chip {
  color: var(--nn-gold-mute);
  border-color: rgba(138, 115, 78, 0.42);
}

.nn-section--paper .nn-chip:hover {
  color: var(--nn-ink);
  border-color: var(--nn-gold-mute);
}

.nn-panel {
  position: relative;
  padding: clamp(1.15rem, 2.6vw, 1.9rem);
  background: rgba(6, 38, 29, 0.55);
  border: 1px solid var(--nn-hairline-soft);
  clip-path: polygon(
    0 0,
    calc(100% - var(--nn-cut)) 0,
    100% var(--nn-cut),
    100% 100%,
    var(--nn-cut) 100%,
    0 calc(100% - var(--nn-cut))
  );
  transition: background-color 0.35s var(--nn-ease), transform 0.35s var(--nn-ease),
    filter 0.35s var(--nn-ease);
}

.nn-panel:hover {
  background: rgba(15, 74, 56, 0.6);
  transform: translateY(-3px);
  filter: drop-shadow(0 18px 34px rgba(0, 0, 0, 0.45));
}

.nn-panel--paper {
  background: var(--nn-paper);
  color: var(--nn-ink);
  border-color: rgba(138, 115, 78, 0.32);
}

.nn-panel--paper:hover { background: #fffaf0; }
.nn-panel--flat { background: transparent; }
.nn-panel--flush { padding: 0; }

.nn-panel__label {
  display: block;
  font-family: var(--nn-font-index);
  font-size: 0.62rem;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--nn-gold-mute);
}

.nn-panel__title {
  margin-top: 0.7rem;
  font-family: var(--nn-font-display);
  font-size: 1.2rem;
  font-weight: 400;
  line-height: 1.4;
  color: var(--nn-paper);
}

.nn-panel--paper .nn-panel__title { color: var(--nn-ink); }

.nn-panel__body {
  margin-top: 0.7rem;
  font-size: 0.94rem;
  line-height: 1.85;
  color: var(--nn-dark-ink);
}

.nn-panel__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 1rem;
  margin-top: 1.1rem;
  font-family: var(--nn-font-index);
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  color: var(--nn-gold-mute);
}

.nn-media {
  position: relative;
  overflow: hidden;
  aspect-ratio: 4 / 3;
  background: linear-gradient(150deg, var(--nn-green) 0%, var(--nn-green-deep) 60%, #123f31 100%);
}

.nn-media--wide { aspect-ratio: 16 / 9; }
.nn-media--tall { aspect-ratio: 3 / 4; }
.nn-media--square { aspect-ratio: 1 / 1; }

.nn-media--cut {
  clip-path: polygon(0 0, 100% 6%, 100% 100%, 0 94%);
}

.nn-media > img,
.nn-media__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.nn-media__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 0.8rem 1rem;
  font-family: var(--nn-font-index);
  font-size: 0.62rem;
  letter-spacing: 0.18em;
  color: var(--nn-gold-soft);
  background: linear-gradient(180deg, rgba(6, 38, 29, 0) 0%, rgba(6, 38, 29, 0.92) 100%);
}

.nn-media--empty::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(
    135deg,
    rgba(176, 141, 87, 0.16) 0 1px,
    transparent 1px 12px
  );
}

.nn-band {
  display: flex;
  gap: 1px;
  overflow-x: auto;
  scroll-snap-type: x proximity;
  padding-bottom: 0.5rem;
  background: var(--nn-hairline-soft);
  scrollbar-width: thin;
  scrollbar-color: var(--nn-gold-mute) transparent;
}

.nn-band::-webkit-scrollbar { height: 4px; }
.nn-band::-webkit-scrollbar-track { background: var(--nn-hairline-soft); }
.nn-band::-webkit-scrollbar-thumb { background: var(--nn-gold-mute); }

.nn-band__item {
  flex: 0 0 clamp(238px, 72vw, 340px);
  scroll-snap-align: start;
  padding: clamp(1.1rem, 3vw, 1.8rem);
  background: var(--nn-green-deep);
}

.nn-fold {
  border-top: 1px solid var(--nn-hairline-soft);
}

.nn-fold:last-child { border-bottom: 1px solid var(--nn-hairline-soft); }

.nn-fold__summary {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1.2rem;
  padding: 1.15rem 0;
  font-family: var(--nn-font-display);
  font-size: clamp(1rem, 1.6vw, 1.18rem);
  line-height: 1.5;
  cursor: pointer;
  list-style: none;
}

.nn-fold__summary::-webkit-details-marker { display: none; }
.nn-fold__summary::marker { content: ""; }

.nn-fold__sign {
  position: relative;
  flex: 0 0 auto;
  width: 1rem;
  height: 1rem;
  margin-top: 0.5rem;
}

.nn-fold__sign::before,
.nn-fold__sign::after {
  content: "";
  position: absolute;
  inset: 50% 0 auto 0;
  height: 1px;
  background: var(--nn-gold);
  transition: transform 0.3s var(--nn-ease);
}

.nn-fold__sign::after { transform: rotate(90deg); }
.nn-fold[open] .nn-fold__sign::after { transform: rotate(0deg); }

.nn-fold__body {
  max-width: 72ch;
  padding-bottom: 1.4rem;
  font-size: 0.95rem;
  line-height: 1.9;
  color: var(--nn-dark-ink);
}

.nn-log { display: grid; }

.nn-log__item {
  position: relative;
  display: grid;
  grid-template-columns: 8.5rem 1fr;
  gap: clamp(1rem, 3vw, 2.4rem);
  padding: 1.5rem 0;
  border-top: 1px solid var(--nn-hairline-soft);
}

.nn-log__item::before {
  content: "";
  position: absolute;
  left: -0.9rem;
  top: 2.05rem;
  width: 0.4rem;
  height: 0.4rem;
  background: var(--nn-red);
  transform: rotate(45deg);
}

.nn-log__date {
  padding-top: 0.35rem;
  font-family: var(--nn-font-index);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  color: var(--nn-gold-mute);
}

.nn-log__title {
  font-family: var(--nn-font-display);
  font-size: 1.12rem;
  font-weight: 400;
  line-height: 1.45;
}

.nn-log__text {
  margin-top: 0.5rem;
  font-size: 0.93rem;
  line-height: 1.85;
  color: var(--nn-dark-ink);
}

.nn-reveal { opacity: 1; }

html.nn-js .nn-reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.8s var(--nn-ease), transform 0.8s var(--nn-ease);
}

html.nn-js .nn-reveal.is-visible {
  opacity: 1;
  transform: none;
}

.nn-to-top {
  position: fixed;
  right: clamp(1rem, 3vw, 2rem);
  bottom: clamp(1rem, 3vw, 2rem);
  z-index: 75;
  display: grid;
  place-items: center;
  width: 2.9rem;
  height: 2.9rem;
  font-size: 1rem;
  color: var(--nn-gold-soft);
  background: rgba(6, 38, 29, 0.92);
  border: 1px solid var(--nn-hairline);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.3s var(--nn-ease), transform 0.3s var(--nn-ease),
    visibility 0.3s var(--nn-ease), background-color 0.3s var(--nn-ease),
    color 0.3s var(--nn-ease);
}

.nn-to-top[data-visible="true"] {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.nn-to-top:hover {
  background: var(--nn-green);
  color: var(--nn-paper);
}

/* 5. 页头 ------------------------------------------------------------------ */
.nn-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 80;
  background: linear-gradient(
    180deg,
    rgba(6, 38, 29, 0.94) 0%,
    rgba(6, 38, 29, 0.62) 62%,
    rgba(6, 38, 29, 0) 100%
  );
}

.nn-header::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  background: var(--nn-green);
  box-shadow: 0 1px 0 var(--nn-hairline), 0 18px 40px -30px rgba(0, 0, 0, 0.9);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.35s var(--nn-ease);
}

.nn-header[data-scrolled="true"]::before,
.nn-header[data-open]::before { opacity: 1; }

.nn-header__inner {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: var(--nn-header-h);
}

.nn-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
}

.nn-brand__mark {
  display: grid;
  place-items: center;
  width: 2.35rem;
  height: 2.35rem;
  font-family: var(--nn-font-display);
  font-size: 1.05rem;
  line-height: 1;
  color: var(--nn-gold-soft);
  background: rgba(11, 59, 46, 0.55);
  border: 1px solid var(--nn-gold-mute);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%);
}

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

.nn-brand__name {
  font-family: var(--nn-font-display);
  font-size: 1.1rem;
  letter-spacing: 0.14em;
  color: var(--nn-paper);
}

.nn-brand__tag {
  margin-top: 0.15rem;
  font-family: var(--nn-font-index);
  font-size: 0.58rem;
  letter-spacing: 0.2em;
  color: var(--nn-gold-mute);
}

.nn-brand--footer .nn-brand__mark {
  background: rgba(11, 59, 46, 0.75);
}

.nn-nav-toggle {
  position: relative;
  z-index: 3;
  display: none;
  align-items: center;
  gap: 0.55rem;
  padding: 0.5rem 0.7rem;
  font-family: var(--nn-font-index);
  font-size: 0.62rem;
  letter-spacing: 0.24em;
  color: var(--nn-gold-soft);
  background: transparent;
  border: 1px solid var(--nn-hairline);
  cursor: pointer;
  transition: color 0.25s var(--nn-ease), border-color 0.25s var(--nn-ease);
}

.nn-nav-toggle:hover {
  color: var(--nn-paper);
  border-color: var(--nn-gold);
}

.nn-nav-toggle__bars {
  display: inline-grid;
  gap: 4px;
  width: 18px;
}

.nn-nav-toggle__bars span {
  display: block;
  height: 1px;
  background: currentColor;
  transition: transform 0.3s var(--nn-ease), opacity 0.2s var(--nn-ease);
}

.nn-header[data-open] .nn-nav-toggle__bars span:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}

.nn-header[data-open] .nn-nav-toggle__bars span:nth-child(2) { opacity: 0; }

.nn-header[data-open] .nn-nav-toggle__bars span:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

.nn-nav-toggle__label { white-space: nowrap; }

.nn-nav {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  gap: clamp(0.9rem, 2.2vw, 2rem);
}

.nn-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(0.8rem, 2vw, 1.75rem);
  counter-reset: nn-nav;
}

.nn-nav__item { counter-increment: nn-nav; }

.nn-nav__link {
  position: relative;
  display: inline-block;
  padding: 0.5rem 0;
  font-size: 0.92rem;
  letter-spacing: 0.06em;
  color: var(--nn-paper);
  transition: color 0.25s var(--nn-ease);
}

.nn-nav__link::before {
  content: counter(nn-nav, decimal-leading-zero);
  margin-right: 0.45rem;
  font-family: var(--nn-font-index);
  font-size: 0.58rem;
  letter-spacing: 0.14em;
  color: var(--nn-gold-mute);
  vertical-align: 0.16em;
}

.nn-nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 100%;
  bottom: 0.15rem;
  height: 1px;
  background: var(--nn-gold);
  transition: right 0.3s var(--nn-ease);
}

.nn-nav__link:hover { color: var(--nn-gold-soft); }
.nn-nav__link:hover::after { right: 0; }

.nn-nav__link[aria-current="page"] { color: var(--nn-gold-soft); }

.nn-nav__link[aria-current="page"]::after {
  right: 0;
  background: var(--nn-red);
}

.nn-nav__cta {
  padding: 0.62rem 1.15rem;
  font-size: 0.74rem;
  letter-spacing: 0.16em;
}

.nn-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 3;
  height: 2px;
  overflow: hidden;
  pointer-events: none;
}

.nn-progress__bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--nn-gold) 0%, var(--nn-gold-soft) 55%, var(--nn-red) 100%);
  transition: width 0.12s linear;
}

/* 6. 页脚 ------------------------------------------------------------------ */
.nn-footer {
  position: relative;
  overflow: hidden;
  background: var(--nn-green-deep);
  color: var(--nn-paper);
  border-top: 1px solid var(--nn-hairline);
}

.nn-footer::before {
  content: "";
  position: absolute;
  left: -6%;
  right: -6%;
  top: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--nn-gold), transparent);
  transform: rotate(-0.6deg);
  pointer-events: none;
}

.nn-footer__inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.7fr);
  gap: clamp(2rem, 5vw, 5rem);
  padding-block: clamp(3rem, 7vw, 5.5rem);
}

.nn-footer__brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 1.2rem;
}

.nn-footer__note {
  max-width: 34ch;
  font-size: 0.94rem;
  line-height: 1.9;
  color: rgba(245, 240, 230, 0.66);
}

.nn-footer__contact {
  display: grid;
  gap: 0.7rem;
  font-size: 0.86rem;
}

.nn-footer__contact-row {
  display: grid;
  grid-template-columns: 5.2rem 1fr;
  gap: 0.6rem;
  align-items: baseline;
}

.nn-footer__contact dt {
  font-family: var(--nn-font-index);
  font-size: 0.62rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--nn-gold-mute);
}

.nn-footer__contact dd {
  line-height: 1.65;
  color: rgba(245, 240, 230, 0.82);
  word-break: break-word;
}

.nn-footer__nav {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(1.4rem, 3vw, 2.6rem);
}

.nn-footer__col { min-width: 0; }

.nn-footer__heading {
  position: relative;
  padding-bottom: 0.8rem;
  font-family: var(--nn-font-display);
  font-size: 0.98rem;
  font-weight: 400;
  letter-spacing: 0.2em;
  color: var(--nn-gold-soft);
}

.nn-footer__heading::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 1.6rem;
  height: 1px;
  background: var(--nn-red);
}

.nn-footer__links {
  display: grid;
  gap: 0.55rem;
  margin-top: 1.1rem;
}

.nn-footer__link {
  position: relative;
  display: inline-block;
  font-size: 0.88rem;
  color: rgba(245, 240, 230, 0.72);
  transition: color 0.25s var(--nn-ease), transform 0.25s var(--nn-ease);
}

.nn-footer__link::before {
  content: "";
  position: absolute;
  left: -0.9rem;
  top: 50%;
  width: 0.5rem;
  height: 1px;
  background: var(--nn-gold);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.3s var(--nn-ease);
}

.nn-footer__link:hover {
  color: var(--nn-gold-soft);
  transform: translateX(0.35rem);
}

.nn-footer__link:hover::before { transform: scaleX(1); }

.nn-footer__base { border-top: 1px solid var(--nn-hairline-soft); }

.nn-footer__base-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.6rem 1.5rem;
  padding-block: 1.4rem;
}

.nn-footer__copy,
.nn-footer__icp {
  font-family: var(--nn-font-index);
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  color: var(--nn-gold-mute);
}

/* 7. 工具类 ---------------------------------------------------------------- */
.nn-visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.nn-skip {
  position: fixed;
  top: 0;
  left: 50%;
  z-index: 200;
  padding: 0.7rem 1.3rem;
  font-family: var(--nn-font-index);
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  color: var(--nn-green-deep);
  background: var(--nn-gold);
  transform: translate(-50%, -140%);
  transition: transform 0.25s var(--nn-ease);
}

.nn-skip:focus { transform: translate(-50%, 0); }

/* 8. 响应式 ---------------------------------------------------------------- */
@media (max-width: 1024px) {
  .nn-footer__inner { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 900px) {
  :root {
    --nn-header-h: 64px;
    --nn-cut: 14px;
  }

  .nn-nav-toggle { display: inline-flex; }

  .nn-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    min-height: 100vh;
    max-height: 100vh;
    overflow-y: auto;
    padding: calc(var(--nn-header-h) + 1.5rem) var(--nn-gutter) 2.5rem;
    background: linear-gradient(180deg, var(--nn-green-deep) 0%, var(--nn-green) 100%);
    border-top: 1px solid var(--nn-hairline);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity 0.3s var(--nn-ease), transform 0.35s var(--nn-ease),
      visibility 0.35s var(--nn-ease);
  }

  .nn-header[data-open] .nn-nav {
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .nn-nav__list {
    display: grid;
    gap: 0;
    width: 100%;
  }

  .nn-nav__item { border-bottom: 1px solid var(--nn-hairline-soft); }

  .nn-nav__link {
    display: block;
    width: 100%;
    padding: 1.05rem 0;
    font-family: var(--nn-font-display);
    font-size: 1.35rem;
    letter-spacing: 0.08em;
  }

  .nn-nav__link::after { display: none; }

  .nn-nav__link::before { font-size: 0.62rem; }

  .nn-nav__cta {
    align-self: stretch;
    margin-top: 2rem;
    padding: 0.9rem 1.4rem;
    font-size: 0.8rem;
  }
}

@media (max-width: 720px) {
  .nn-footer__nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .nn-brand__tag { letter-spacing: 0.14em; }

  .nn-log__item {
    grid-template-columns: minmax(0, 1fr);
    gap: 0.4rem;
  }

  .nn-log__item::before { display: none; }

  .nn-log__date { padding-top: 0; }

  .nn-footer__contact-row { grid-template-columns: minmax(0, 1fr); gap: 0.15rem; }

  .nn-footer__base-inner { justify-content: flex-start; }
}

@media (max-width: 420px) {
  .nn-brand__tag { display: none; }
  .nn-nav-toggle__label { display: none; }
}

/* 9. 动效降级 -------------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    transition-delay: 0ms !important;
  }

  html.nn-js .nn-reveal {
    opacity: 1 !important;
    transform: none !important;
  }

  .nn-panel:hover { transform: none; }
  .nn-btn:hover { transform: none; }
  .nn-footer__link:hover { transform: none; }
  .nn-progress__bar { transition: none; }
}