/* IS&T imaging.org.cn — design inspired by imaging.org */

/* Colors sampled from www.imaging.org */
:root {
  --navy:     #004a80;   /* primary nav bar */
  --navy-dk:  #003860;
  --blue:     #145098;   /* section heading bars (h2) */
  --logo-blue:#005dab;   /* logo / brand blue */
  --orange:   #e68600;   /* accents, submit links, sidebar labels */
  --orange-h: #c97400;
  --black:    #0c0c0c;   /* body text */
  --h1-gray:  #737373;   /* page titles */
  --gray-dk:  #444444;
  --gray:     #666666;
  --gray-lt:  #888888;
  --border:   #cccccc;
  --sidebar-bg:#eeeeee;  /* left-nav section labels */
  --bg:       #f5f5f5;
  --white:    #ffffff;
  --max:      1060px;
  --font:     Arial, "Helvetica Neue", Helvetica, sans-serif;
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  font-size: 14px;
  line-height: 1.55;
  color: var(--black);
  background: var(--white);
}

a { color: var(--orange); text-decoration: none; }
a:hover { text-decoration: underline; color: var(--orange-h); }

h1, h2, h3, h4 { font-family: var(--font); font-weight: bold; }
h1 { font-size: 1.7em; margin: 0 0 4px; color: var(--h1-gray); }
h2 { font-size: 1.2em; margin: 0; }
h3 { font-size: 1em; margin: 0 0 6px; color: var(--orange); }
h4 { font-size: 0.95em; margin: 0 0 4px; }
p  { margin: 0 0 10px; }

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

/* ── Top utility bar ── */
.top-bar {
  background: var(--white);
  border-bottom: 1px solid var(--border);
  padding: 8px 0;
}

.top-bar-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.logo-block {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--black);
}

.logo-banner {
  height: 76px;
  width: auto;
  max-width: min(400px, 70vw);
  object-fit: contain;
  object-position: left center;
}

.logo-text {
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.logo-text .soc-name {
  font-family: Georgia, "Times New Roman", Times, serif;
  font-size: 15px;
  font-style: italic;
  color: var(--logo-blue);
  font-weight: normal;
  line-height: 1.25;
}

.logo-text .soc-url {
  font-size: 12px;
  color: var(--logo-blue);
  font-weight: bold;
}

.top-bar-right {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 12px;
}

.top-bar-right a { color: var(--logo-blue); text-decoration: none; }
.top-bar-right a:hover { color: var(--orange); text-decoration: underline; }

.social-icons {
  display: flex;
  align-items: center;
  gap: 8px;
}

.social-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 3px;
  text-decoration: none !important;
}

.social-icon svg {
  width: 18px;
  height: 18px;
  display: block;
}

/* ── Primary nav ── */
.primary-nav {
  background: var(--navy);
  position: sticky;
  top: 0;
  z-index: 100;
}

.primary-nav-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 16px;
  display: flex;
  align-items: stretch;
}

.primary-nav ul {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
  gap: 0;
}

.primary-nav > .primary-nav-inner > ul > li {
  position: relative;
}

.primary-nav > .primary-nav-inner > ul > li > a {
  display: block;
  padding: 13px 16px;
  color: var(--white);
  text-decoration: none;
  font-size: 12.5px;
  font-weight: bold;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  transition: background 0.15s;
}

.primary-nav > .primary-nav-inner > ul > li > a:hover,
.primary-nav > .primary-nav-inner > ul > li > a[aria-current] {
  background: var(--navy-dk);
  text-decoration: none;
}

/* dropdown */
.primary-nav .dropdown {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 220px;
  background: var(--white);
  border: 1px solid var(--border);
  border-top: 2px solid var(--orange);
  box-shadow: 0 4px 12px rgba(0,0,0,0.12);
  list-style: none;
  margin: 0;
  padding: 6px 0;
  z-index: 200;
}

.primary-nav li:hover > .dropdown,
.primary-nav li:focus-within > .dropdown { display: block; }

.primary-nav .dropdown a {
  display: block;
  padding: 7px 14px;
  font-size: 12.5px;
  color: var(--black);
  text-decoration: none;
}

.primary-nav .dropdown a:hover {
  background: var(--bg);
  color: var(--orange);
  text-decoration: none;
}

/* mobile toggle */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--white);
  font-size: 20px;
  padding: 12px 16px;
  cursor: pointer;
  margin-left: auto;
}

/* ── Layout ── */
.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 16px;
}

/* two-column page layout */
.page-layout {
  max-width: var(--max);
  margin: 0 auto;
  padding: 16px 16px 40px;
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 24px;
  align-items: start;
}

/* breadcrumb */
.breadcrumb {
  background: var(--white);
  border-bottom: 1px solid var(--border);
  padding: 7px 0;
  font-size: 12px;
  color: var(--gray);
}

.breadcrumb-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 16px;
  display: flex;
  flex-wrap: wrap;
  gap: 0 4px;
  align-items: center;
}

.breadcrumb a { color: var(--navy); }
.breadcrumb a:hover { color: var(--orange); }
.breadcrumb .sep { color: var(--gray-lt); }

/* ── Left sidebar ── */
.sidebar {
  font-size: 12.5px;
}

.sidebar-section {
  margin-bottom: 14px;
}

.sidebar-label {
  font-size: 12px;
  font-weight: bold;
  color: var(--orange);
  background: var(--sidebar-bg);
  padding: 5px 8px;
  margin: 0 0 2px;
}

.sidebar ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.sidebar li a {
  display: block;
  padding: 4px 8px;
  color: var(--black);
  font-size: 12px;
  border-bottom: 1px solid #e8e8e8;
}

.sidebar li a:hover,
.sidebar li a[aria-current] {
  color: var(--orange);
  text-decoration: underline;
}

/* ── Main content ── */
/* section heading bars — match imaging.org h2 style */
.section-bar {
  background: var(--blue);
  color: var(--white);
  font-size: 18px;
  font-weight: bold;
  padding: 2px 6px;
  margin: 18px 0 10px;
}

.content h1 {
  font-size: 1.6em;
  margin: 0 0 6px;
  color: var(--h1-gray);
}

.submit-link {
  display: inline-block;
  font-size: 15px;
  color: var(--orange);
  font-weight: bold;
  margin-bottom: 14px;
  text-transform: uppercase;
}

.content p, .content ul, .content ol {
  font-size: 13.5px;
  line-height: 1.6;
  color: var(--black);
}

.content ul, .content ol {
  padding-left: 22px;
  margin: 0 0 10px;
}

.content li { margin-bottom: 3px; }

.content h3 {
  font-size: 13.5px;
  margin: 14px 0 5px;
  color: var(--black);
}

.content h4 {
  font-size: 13px;
  margin: 12px 0 4px;
  color: var(--navy);
}

.callout {
  border: 1px solid var(--border);
  background: var(--bg);
  padding: 12px 14px;
  margin-bottom: 14px;
  font-size: 13px;
}

.callout h3 {
  text-align: center;
  font-size: 13px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin: 0 0 8px;
  color: var(--black);
}

/* ── Homepage ── */
.home-hero {
  background: var(--navy);
  padding: 28px 0 22px;
  color: var(--white);
}

.home-hero-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 28px 16px 22px;
}

.home-hero h1 {
  font-size: 1.55em;
  color: var(--white);
  margin-bottom: 10px;
}

.home-hero p {
  font-size: 13.5px;
  color: rgba(255,255,255,0.88);
  max-width: 480px;
}

.hero-logo-panel {
  text-align: center;
  padding: 16px;
  border: 1px solid rgba(255,255,255,0.2);
  background: rgba(255,255,255,0.95);
}

.hero-logo-panel img {
  filter: none;
}

.home-body {
  max-width: var(--max);
  margin: 0 auto;
  padding: 24px 16px 40px;
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 28px;
  align-items: start;
}

.home-section-title {
  background: var(--blue);
  color: var(--white);
  font-size: 18px;
  font-weight: bold;
  padding: 2px 6px;
  margin: 0 0 12px;
}

.journals-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 4px;
}

.journal-card {
  border: 1px solid var(--border);
  background: var(--white);
  padding: 12px;
  display: flex;
  flex-direction: column;
}

.journal-card .jabbr {
  font-size: 11px;
  font-weight: bold;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--orange);
  margin-bottom: 4px;
}

.journal-card h3 {
  font-size: 13px;
  color: var(--navy);
  margin-bottom: 7px;
}

.journal-card p {
  font-size: 12.5px;
  color: var(--gray-dk);
  flex: 1;
  margin-bottom: 10px;
}

.journal-card a.more {
  font-size: 12px;
  color: var(--orange);
  font-weight: bold;
}

.activity-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.activity-list li {
  padding: 9px 0;
  border-bottom: 1px solid #e4e4e4;
  font-size: 13px;
}

.activity-list li:last-child { border-bottom: none; }

.activity-list .aname {
  font-weight: bold;
  color: var(--navy);
  display: block;
  margin-bottom: 2px;
}

.activity-list .adesc { color: var(--gray-dk); }

/* about sidebar box */
.info-box {
  border: 1px solid var(--border);
  padding: 14px;
  font-size: 12.5px;
  background: var(--white);
}

.info-box h3 {
  font-size: 13px;
  color: var(--navy);
  margin-bottom: 7px;
  border-bottom: 1px solid var(--border);
  padding-bottom: 5px;
}

.info-box p, .info-box address {
  color: var(--gray-dk);
  font-style: normal;
  margin-bottom: 8px;
  font-size: 12.5px;
}

.info-box a { color: var(--navy); }

/* ── Footer ── */
.site-footer {
  background: var(--navy);
  color: rgba(255,255,255,0.8);
  padding: 20px 0 14px;
  font-size: 12px;
}

.footer-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 16px;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  margin-bottom: 12px;
}

.footer-links a {
  color: rgba(255,255,255,0.85);
  text-decoration: none;
  font-size: 12px;
}

.footer-links a:hover { text-decoration: underline; color: var(--white); }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.2);
  padding-top: 10px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 6px;
  color: rgba(255,255,255,0.6);
  font-size: 11.5px;
}

/* ── Responsive ── */
@media (max-width: 768px) {
  .home-hero-inner,
  .home-body {
    grid-template-columns: 1fr;
  }

  .hero-logo-panel { display: none; }

  .page-layout {
    grid-template-columns: 1fr;
  }

  .sidebar { display: none; }

  .journals-grid {
    grid-template-columns: 1fr;
  }

  .logo-banner {
    height: 56px;
  }

  .top-search {
    display: none;
  }

  .nav-toggle { display: block; }

  .primary-nav ul {
    display: none;
    flex-direction: column;
  }

  .primary-nav ul.is-open { display: flex; }

  .primary-nav > .primary-nav-inner > ul > li > a {
    padding: 10px 16px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
  }

  .primary-nav .dropdown {
    position: static;
    box-shadow: none;
    border: none;
    border-top: none;
    background: rgba(255,255,255,0.05);
    padding: 0 0 0 12px;
  }

  .primary-nav li:hover > .dropdown,
  .primary-nav li:focus-within > .dropdown { display: block; }
}

/* ── ICP / 公安联网备案 footer ── */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg);
  margin-top: 24px;
  padding: 14px 0;
}

.site-footer-inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 16px;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
  font-size: 12px;
  color: var(--gray);
}

.site-footer a { color: var(--gray); }
.site-footer a:hover { color: var(--gray-dk); }

.police-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.police-link img {
  display: inline-block;
  vertical-align: middle;
}

@media (max-width: 640px) {
  .site-footer-inner {
    gap: 12px;
  }
}