/* ============================================================
   EMC 全站登录中心 — /assets/site.css
   共享外壳 / 排版底座 / 通用组件
   ============================================================ */

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; scroll-padding-top: 132px; }

body,
h1, h2, h3, h4, h5, p, figure, blockquote, dl, dd, ul, ol, pre { margin: 0; }

ul, ol { padding: 0; margin: 0; list-style: none; }

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

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

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

hr { border: 0; }

/* ---------- 2. Tokens ---------- */
:root {
  --navy: #071B2E;
  --navy-2: #0C2A44;
  --steel: #1B4A6B;
  --mist: #A9C3D6;
  --paper: #F4F7F8;
  --ink: #0A0F14;
  --signal: #FF6B35;
  --amber: #FFB27A;
  --mint: #4FD1B5;
  --slate: #5C7A8E;

  --bg: var(--navy);
  --bg-2: var(--navy-2);
  --fg: #E6EDF2;
  --fg-dim: var(--mist);
  --on-accent: var(--ink);
  --line: rgba(169, 195, 214, 0.22);
  --line-strong: rgba(169, 195, 214, 0.44);
  --accent: var(--signal);
  --accent-soft: var(--amber);
  --ok: var(--mint);
  --aside: var(--slate);
  --stack-a: rgba(27, 74, 107, 0.65);
  --stack-b: rgba(27, 74, 107, 0.3);

  --font-display: 'Barlow Condensed', 'Oswald', 'Noto Sans SC', 'PingFang SC', sans-serif;
  --font-body: 'HarmonyOS Sans SC', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', 'IBM Plex Mono', 'SFMono-Regular', ui-monospace, monospace;

  --shell: min(1200px, 100% - 2.5rem);
  --ease: cubic-bezier(0.22, 0.68, 0.28, 1);
}

/* ---------- 3. Base ---------- */
html, body { min-height: 100%; }

body {
  background: var(--navy);
  color: var(--fg);
  font-family: var(--font-body);
  font-size: clamp(16px, 0.55vw + 13.4px, 18px);
  line-height: 1.75;
  letter-spacing: 0.005em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

::selection { background: var(--accent); color: var(--on-accent); }

:where(a, button, input, select, textarea, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

/* ---------- 4. Layout utilities ---------- */
.shell {
  width: var(--shell);
  margin-inline: auto;
}

.section { padding-block: clamp(2.5rem, 5vw, 4.5rem); }
.section--tight { padding-block: clamp(1.5rem, 3vw, 2.5rem); }

.page-head {
  display: grid;
  gap: 1rem;
  padding-block: clamp(1.5rem, 3.5vw, 2.75rem) clamp(1rem, 2vw, 1.75rem);
}

.grid { display: grid; gap: clamp(1rem, 2.4vw, 2rem); }
.grid--7-5 { grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }
.grid--8-4 { grid-template-columns: minmax(0, 8fr) minmax(0, 4fr); }
.grid--9-3 { grid-template-columns: minmax(0, 9fr) minmax(0, 3fr); }
.grid--thirds { grid-template-columns: repeat(3, minmax(0, 1fr)); }

.stack { display: grid; gap: 1rem; }

/* ---------- 5. Typography ---------- */
.display {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2.4rem, 6vw, 5.2rem);
  line-height: 0.94;
  letter-spacing: -0.005em;
  color: var(--fg);
  text-wrap: balance;
}

.display--sm {
  font-size: clamp(1.75rem, 3.4vw, 2.85rem);
  line-height: 1.04;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin: 0;
}

.eyebrow::before {
  content: "";
  flex: none;
  width: 26px;
  height: 2px;
  background: var(--accent);
}

.lede {
  max-width: 62ch;
  font-size: clamp(1rem, 0.9vw + 0.72rem, 1.16rem);
  line-height: 1.8;
  color: var(--fg-dim);
}

.meta {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--aside);
  text-transform: uppercase;
}

.prose { max-width: 68ch; }
.prose > * + * { margin-top: 1rem; }
.prose h2,
.prose h3 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.15;
  color: var(--fg);
}
.prose h2 { font-size: clamp(1.5rem, 2.4vw, 2rem); margin-top: 2rem; }
.prose h3 { font-size: clamp(1.15rem, 1.6vw, 1.4rem); margin-top: 1.6rem; }
.prose p { color: var(--fg-dim); }
.prose a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}
.prose a:hover { color: var(--accent-soft); }
.prose ul { list-style: square; padding-left: 1.2em; }
.prose ol { list-style: decimal; padding-left: 1.35em; }
.prose li { color: var(--fg-dim); margin-bottom: 0.4em; }
.prose strong { color: var(--fg); font-weight: 600; }

.rule { height: 1px; background: var(--line); }
.rule--accent {
  height: 3px;
  background: linear-gradient(90deg, var(--accent) 0 64px, var(--line) 64px);
}

/* ---------- 6. Buttons ---------- */
.btn {
  --btn-bg: transparent;
  --btn-fg: var(--fg);
  --btn-bd: var(--line-strong);
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.72rem 1.15rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  color: var(--btn-fg);
  background: var(--btn-bg);
  border: 1px solid var(--btn-bd);
  cursor: pointer;
  text-decoration: none;
  transition: background 0.2s var(--ease), color 0.2s var(--ease),
    border-color 0.2s var(--ease), transform 0.2s var(--ease);
}

.btn:hover { transform: translateY(-1px); }

.btn--signal {
  --btn-bg: var(--accent);
  --btn-fg: var(--on-accent);
  --btn-bd: var(--accent);
}
.btn--signal:hover {
  --btn-bg: var(--accent-soft);
  --btn-bd: var(--accent-soft);
}

.btn--ghost:hover {
  --btn-bg: rgba(169, 195, 214, 0.1);
  --btn-fg: var(--fg);
}

.btn--mint {
  --btn-fg: var(--ok);
  --btn-bd: var(--ok);
}
.btn--mint:hover {
  --btn-bg: rgba(79, 209, 181, 0.14);
}

.btn--sm {
  padding: 0.48rem 0.78rem;
  font-size: 0.72rem;
  letter-spacing: 0.08em;
}

/* ---------- 7. Tags & status ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.22rem 0.55rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--fg-dim);
  background: rgba(169, 195, 214, 0.06);
  border: 1px solid var(--line-strong);
}

.tag--signal {
  color: var(--amber);
  background: rgba(255, 107, 53, 0.12);
  border-color: rgba(255, 107, 53, 0.45);
}

.tag--mint {
  color: var(--mint);
  background: rgba(79, 209, 181, 0.12);
  border-color: rgba(79, 209, 181, 0.45);
}

.status-dot {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--fg-dim);
  white-space: nowrap;
}

.status-dot::before {
  content: "";
  flex: none;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--aside);
}

.status-dot[data-state="live"]::before {
  background: var(--ok);
  animation: lampPulse 2.4s ease-in-out infinite;
}

.status-dot[data-state="warn"]::before { background: var(--accent-soft); }
.status-dot[data-state="idle"]::before { background: var(--aside); }

@keyframes lampPulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(79, 209, 181, 0.5); }
  50% { box-shadow: 0 0 0 5px rgba(79, 209, 181, 0); }
}

/* ---------- 8. Panel ---------- */
.panel {
  position: relative;
  padding: clamp(1rem, 2vw, 1.75rem);
  background: var(--bg-2);
  border: 1px solid var(--line);
}

.panel--stack {
  box-shadow: 6px 6px 0 0 var(--stack-a), 12px 12px 0 0 var(--stack-b);
}

.panel__head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding-bottom: 0.75rem;
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--line);
}

.panel__body { display: grid; gap: 0.85rem; }

/* ---------- 9. Breadcrumb ---------- */
.breadcrumb {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--aside);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  align-items: center;
}

.breadcrumb li { display: inline-flex; align-items: center; gap: 0.45rem; }
.breadcrumb li:not(:first-child)::before { content: "/"; color: var(--line-strong); }
.breadcrumb a:hover { color: var(--accent); }
.breadcrumb [aria-current="page"] { color: var(--fg-dim); }

/* ---------- 10. Media frame ---------- */
.media-frame {
  position: relative;
  margin: 0;
  overflow: hidden;
  background: linear-gradient(135deg, rgba(27, 74, 107, 0.95), rgba(7, 27, 46, 0.98));
  border: 1px solid var(--line);
}

.media-frame > img,
.media-frame > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.72) contrast(1.04);
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    90deg,
    rgba(169, 195, 214, 0.16) 0 1px,
    transparent 1px 28px
  );
  opacity: 0.35;
}

.media-frame--16x9 { aspect-ratio: 16 / 9; }
.media-frame--4x5 { aspect-ratio: 4 / 5; }
.media-frame--1x1 { aspect-ratio: 1 / 1; }

.media-frame figcaption {
  position: absolute;
  left: 0;
  bottom: 0;
  padding: 0.45rem 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: var(--mist);
  background: rgba(7, 27, 46, 0.82);
  border-top: 1px solid var(--line);
  border-right: 1px solid var(--line);
}

/* ---------- 11. Skip link ---------- */
.skip-link {
  position: fixed;
  top: 0.5rem;
  left: 50%;
  z-index: 300;
  padding: 0.6rem 1rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  color: var(--ink);
  background: var(--signal);
  transform: translate(-50%, -220%);
  transition: transform 0.18s var(--ease);
}

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

/* ---------- 12. Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--navy);
  border-bottom: 1px solid var(--line);
}

.masthead {
  background: linear-gradient(180deg, #08203A 0%, #071B2E 100%);
}

.masthead__rail {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  grid-template-areas: "edition brand tools";
  align-items: center;
  gap: 1rem;
  padding-block: 0.8rem 0.65rem;
}

.masthead__edition {
  grid-area: edition;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--aside);
  white-space: nowrap;
}

.masthead__edition::before {
  content: "";
  flex: none;
  width: 6px;
  height: 6px;
  background: var(--signal);
}

.brand {
  grid-area: brand;
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  justify-self: center;
  color: var(--fg);
  text-decoration: none;
}

.brand__mark {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.45rem;
  line-height: 1;
  letter-spacing: 0.16em;
  padding: 0.24rem 0.5rem 0.16rem;
  color: var(--fg);
  background: rgba(255, 107, 53, 0.12);
  border: 1px solid var(--line-strong);
  transition: background 0.2s var(--ease), color 0.2s var(--ease);
}

.brand:hover .brand__mark {
  background: var(--signal);
  color: var(--ink);
  border-color: var(--signal);
}

.brand__name {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.24em;
  color: var(--mist);
  white-space: nowrap;
}

.masthead__tools {
  grid-area: tools;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 0.9rem;
}

.masthead__cta { flex: none; }

.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.7rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--fg);
  background: transparent;
  border: 1px solid var(--line-strong);
  cursor: pointer;
}

.nav-toggle__bars {
  display: grid;
  gap: 3px;
  width: 16px;
}

.nav-toggle__bars i {
  display: block;
  height: 2px;
  background: currentColor;
}

.nav-toggle[aria-expanded="true"] {
  color: var(--ink);
  background: var(--signal);
  border-color: var(--signal);
}

.site-nav {
  border-top: 1px solid var(--line);
  background: #06182A;
}

.site-nav__list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.2rem;
  width: var(--shell);
  margin-inline: auto;
  padding-block: 0.3rem;
}

.site-nav__link {
  display: inline-block;
  padding: 0.55rem 0.85rem;
  font-size: 0.92rem;
  letter-spacing: 0.06em;
  color: var(--mist);
  border: 1px solid transparent;
  transition: color 0.18s var(--ease), background 0.18s var(--ease);
}

.site-nav__link:hover {
  color: var(--fg);
  background: rgba(169, 195, 214, 0.08);
}

.site-nav__link[aria-current="page"] {
  color: var(--fg);
  background: rgba(255, 107, 53, 0.14);
  box-shadow: inset 0 -2px 0 var(--signal);
}

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  transform: scaleX(var(--p, 0));
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--signal), var(--amber));
  pointer-events: none;
  transition: transform 0.12s linear;
}

/* ---------- 13. Footer ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(3rem, 6vw, 6rem);
  background: #04121F;
  border-top: 1px solid var(--line-strong);
  color: var(--fg);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: min(38%, 420px);
  height: 2px;
  background: linear-gradient(90deg, var(--signal), rgba(255, 107, 53, 0));
}

.site-footer__inner {
  padding-block: clamp(2.25rem, 4vw, 3.5rem) 1.5rem;
}

.site-footer__top {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  gap: clamp(1.75rem, 4vw, 3.5rem);
  padding-bottom: clamp(1.75rem, 3vw, 2.5rem);
}

.site-footer__pitch {
  max-width: 34ch;
  margin: 0.9rem 0 1.35rem;
  font-size: 0.95rem;
  line-height: 1.72;
  color: var(--mist);
}

.site-footer__contact {
  display: grid;
  gap: 0.4rem;
  padding-left: 0.9rem;
  border-left: 2px solid rgba(255, 107, 53, 0.6);
}

.site-footer__row {
  display: flex;
  gap: 0.6rem;
  align-items: baseline;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  line-height: 1.6;
  letter-spacing: 0.03em;
  color: var(--mist);
}

.site-footer__k {
  flex: none;
  min-width: 3.2em;
  color: var(--aside);
}

.site-footer__nav {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.5rem;
}

.site-footer__colTitle {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0 0 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 400;
  letter-spacing: 0.16em;
  color: var(--mist);
}

.site-footer__colTitle::before {
  content: "";
  width: 14px;
  height: 1px;
  background: var(--signal);
}

.site-footer__col ul { display: grid; gap: 0.5rem; }

.site-footer__col a {
  display: inline-block;
  padding-bottom: 1px;
  font-size: 0.92rem;
  color: var(--fg);
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.site-footer__col a:hover {
  color: var(--amber);
  border-bottom-color: rgba(255, 178, 122, 0.5);
}

.site-footer__base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1.5rem;
  padding-top: 1.1rem;
  border-top: 1px solid rgba(169, 195, 214, 0.16);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--aside);
}

.site-footer__copy { margin: 0; }

.site-footer__legal {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.site-footer__legal a {
  color: var(--mist);
  transition: color 0.18s var(--ease);
}

.site-footer__legal a:hover { color: var(--amber); }

.site-footer__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin: 0;
}

/* ---------- 14. To top ---------- */
.to-top {
  position: fixed;
  right: clamp(0.9rem, 3vw, 1.75rem);
  bottom: clamp(0.9rem, 3vw, 1.75rem);
  z-index: 90;
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  font-family: var(--font-mono);
  font-size: 1rem;
  color: var(--amber);
  background: var(--navy-2);
  border: 1px solid var(--line-strong);
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transform: translateY(10px);
  transition: opacity 0.2s var(--ease), transform 0.2s var(--ease),
    background 0.2s var(--ease), color 0.2s var(--ease);
}

.to-top[data-visible] {
  opacity: 1;
  pointer-events: auto;
  transform: none;
}

.to-top:hover {
  background: var(--steel);
  color: var(--signal);
}

/* ---------- 15. Paper surface ---------- */
.surface-paper {
  --bg: var(--paper);
  --bg-2: #FFFFFF;
  --fg: var(--ink);
  --fg-dim: #40586A;
  --on-accent: #FFFFFF;
  --line: rgba(10, 15, 20, 0.14);
  --line-strong: rgba(10, 15, 20, 0.3);
  --accent: #D24B19;
  --accent-soft: #A83B11;
  --ok: #12705E;
  --aside: #5C7A8E;
  --stack-a: rgba(10, 15, 20, 0.1);
  --stack-b: rgba(10, 15, 20, 0.05);
  background: var(--bg);
  color: var(--fg);
}

.surface-paper .tag--signal {
  color: #9C3510;
  background: rgba(210, 75, 25, 0.08);
  border-color: rgba(210, 75, 25, 0.4);
}

.surface-paper .tag--mint {
  color: #0F6B59;
  background: rgba(18, 112, 94, 0.08);
  border-color: rgba(18, 112, 94, 0.38);
}

.surface-paper .media-frame {
  background: linear-gradient(135deg, #DDE8EF, #C4D6E2);
}

.surface-paper .media-frame::after {
  background-image: repeating-linear-gradient(
    90deg,
    rgba(10, 15, 20, 0.14) 0 1px,
    transparent 1px 28px
  );
}

.surface-paper .media-frame figcaption {
  color: #2F4657;
  background: rgba(255, 255, 255, 0.86);
}

/* ---------- 16. Responsive ---------- */
@media (max-width: 1024px) {
  .grid--thirds { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 960px) {
  .grid--7-5,
  .grid--8-4,
  .grid--9-3 { grid-template-columns: minmax(0, 1fr); }

  html { scroll-padding-top: 108px; }
}

@media (max-width: 880px) {
  .masthead__rail {
    grid-template-columns: minmax(0, 1fr) auto;
    grid-template-areas: "brand tools";
    padding-block: 0.7rem;
  }

  .masthead__edition { display: none; }
  .brand { justify-self: start; }
  .status-dot { display: none; }
  .masthead__cta { display: none; }

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

  .site-nav { display: none; }
  .site-nav[data-open] { display: block; }

  .site-nav__list {
    flex-direction: column;
    flex-wrap: nowrap;
    width: 100%;
    padding-block: 0.4rem 0.8rem;
    gap: 0;
  }

  .site-nav__list li { border-bottom: 1px solid rgba(169, 195, 214, 0.12); }
  .site-nav__list li:last-child { border-bottom: 0; }

  .site-nav__link {
    display: block;
    padding: 0.9rem 1.25rem;
    font-size: 0.95rem;
  }

  .site-nav__link[aria-current="page"] {
    padding-left: 1.1rem;
    box-shadow: inset 3px 0 0 var(--signal);
  }

  .site-footer__top { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 760px) {
  .site-footer__nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .site-footer__base { justify-content: flex-start; }
}

@media (max-width: 540px) {
  :root { --shell: calc(100% - 1.6rem); }

  body { line-height: 1.72; }

  .site-footer__nav { grid-template-columns: minmax(0, 1fr); }
  .site-footer__pitch { max-width: none; }

  .panel { padding: 1rem; }
  .panel--stack { box-shadow: 4px 4px 0 0 var(--stack-a); }
}

/* ---------- 17. Reduced motion ---------- */
@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;
  }

  .btn:hover { transform: none; }
  .to-top { transform: none; }
  .scroll-progress { transition: none; }
  .status-dot[data-state="live"]::before { animation: none; }
}