/* ==========================================================================
   Remote Sensing Researcher Theme — Bootstrap 5
   Earth-observation inspired: deep space navy, orbital teal/green accents,
   satellite flight-deck motifs. Fonts via Google CDN with system fallbacks.
   ========================================================================== */

:root {
  --rs-space-950: #07090f;
  --rs-space-900: #0b1220;
  --rs-space-800: #111a2e;
  --rs-space-700: #1a2740;
  --rs-navy: #14213d;
  --rs-teal: #2dd4bf;
  --rs-teal-600: #14b8a6;
  --rs-green: #34d399;
  --rs-gold: #fcd34d;
  --rs-ink: #1f2937;
  --rs-ink-soft: #4b5563;
  --rs-muted: #6b7280;
  --rs-bg: #f4f7fa;
  --rs-paper: #ffffff;
  --rs-line: #e3e9f0;
  --rs-shadow: 0 10px 30px rgba(9, 18, 32, 0.10);
  --rs-shadow-sm: 0 4px 14px rgba(9, 18, 32, 0.08);
  --rs-font: "Inter", "Noto Sans SC", "Segoe UI", "PingFang SC",
    "Microsoft YaHei", sans-serif;
  --rs-mono: "JetBrains Mono", "SFMono-Regular", Consolas, monospace;
}

* {
  scrollbar-width: thin;
  scrollbar-color: var(--rs-teal) var(--rs-bg);
}

::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-track {
  background: var(--rs-bg);
}
::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, var(--rs-teal), var(--rs-green));
  border-radius: 5px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--rs-font);
  background: var(--rs-bg);
  color: var(--rs-ink);
  -webkit-font-smoothing: antialiased;
  line-height: 1.7;
}

a {
  color: var(--rs-teal-600);
  text-decoration: none;
  transition: color 0.15s ease;
}
a:hover {
  color: var(--rs-space-800);
  text-decoration: underline;
}

/* ===== Navbar ========================================================= */

.rs-navbar {
  background: rgba(7, 9, 15, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(45, 212, 191, 0.25);
  box-shadow: 0 2px 18px rgba(0, 0, 0, 0.35);
}

.rs-navbar .navbar-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  font-weight: 700;
  letter-spacing: 0.02em;
  font-size: 1.15rem;
}
.rs-navbar .navbar-brand:hover {
  color: var(--rs-teal);
  text-decoration: none;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 9px;
  color: var(--rs-space-950);
  background: linear-gradient(135deg, var(--rs-teal), var(--rs-green));
  box-shadow: 0 0 0 3px rgba(45, 212, 191, 0.2);
  font-size: 1rem;
}

.rs-navbar .nav-link {
  color: rgba(255, 255, 255, 0.78);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 0.5rem 0.85rem !important;
  border-radius: 8px;
  transition: all 0.15s ease;
}
.rs-navbar .nav-link .nav-icon {
  font-size: 0.85rem;
}
.rs-navbar .nav-link:hover {
  color: #fff;
  background: rgba(45, 212, 191, 0.12);
  text-decoration: none;
}
.rs-navbar .nav-item.active .nav-link {
  color: #fff;
  background: linear-gradient(
    135deg,
    rgba(45, 212, 191, 0.25),
    rgba(52, 211, 153, 0.14)
  );
  box-shadow: inset 0 0 0 1px rgba(45, 212, 191, 0.35);
}

.lang-switch {
  border-color: rgba(255, 255, 255, 0.4);
  border-radius: 20px;
  font-weight: 600;
  padding: 0.35rem 1rem;
}
.lang-switch:hover {
  background: var(--rs-teal);
  border-color: var(--rs-teal);
  color: var(--rs-space-950);
  text-decoration: none;
}

.rs-navbar .navbar-toggler {
  border-color: rgba(255, 255, 255, 0.35);
}
.rs-navbar .navbar-toggler:focus {
  box-shadow: none;
}

@media (max-width: 991.98px) {
  .rs-navbar .nav-link {
    padding-left: 0.5rem !important;
  }
}

/* ===== Hero band ====================================================== */

.rs-hero {
  position: relative;
  overflow: hidden;
  padding: 64px 0 58px;
  color: #fff;
  background:
    radial-gradient(60% 120% at 12% 0%, rgba(45, 212, 191, 0.18), transparent 60%),
    radial-gradient(50% 110% at 88% 20%, rgba(52, 211, 153, 0.16), transparent 55%),
    radial-gradient(80% 140% at 50% 120%, rgba(20, 33, 61, 0.9), transparent 70%),
    linear-gradient(160deg, #0b1220 0%, #111a2e 55%, #14213d 100%);
  border-bottom: 1px solid rgba(45, 212, 191, 0.3);
}

.rs-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(45, 212, 191, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(45, 212, 191, 0.06) 1px, transparent 1px);
  background-size: 44px 44px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.55), transparent 95%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.55), transparent 95%);
  pointer-events: none;
}

.rs-hero-title {
  margin: 0;
  font-size: clamp(1.9rem, 4.4vw, 3rem);
  font-weight: 700;
  letter-spacing: 0.02em;
  background: linear-gradient(90deg, #ffffff 20%, var(--rs-teal) 70%, var(--rs-green));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  text-shadow: 0 0 30px rgba(45, 212, 191, 0.25);
}

.rs-hero-sub {
  margin-top: 10px;
  color: rgba(255, 255, 255, 0.78);
  font-size: 1.02rem;
  font-weight: 400;
}

.rs-hero-grid {
  position: absolute;
  top: 12px;
  left: 0;
  right: 0;
  display: flex;
  justify-content: space-between;
  padding: 0 5%;
  color: rgba(45, 212, 191, 0.28);
  font-family: var(--rs-mono);
  font-size: 12px;
  letter-spacing: 0.18em;
}

/* ===== Main ============================================================ */

.rs-main {
  min-height: 60vh;
}

.rs-main .container {
  background: transparent;
}

.rs-main p {
  line-height: 1.8;
}

/* ===== Profile card (home) ============================================ */

.rs-profile-card {
  border-radius: 16px;
  overflow: hidden;
  box-shadow: var(--rs-shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.rs-profile-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--rs-shadow);
}

.profile-photo {
  position: relative;
  background: var(--rs-space-900);
}
.profile-photo img {
  width: 100%;
  display: block;
}

.profile-photo-badge {
  position: absolute;
  top: 10px;
  right: 10px;
}
.profile-photo-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: none;
  border-radius: 50%;
  color: #fff;
  background: rgba(7, 9, 15, 0.55);
  backdrop-filter: blur(4px);
  transition: background 0.15s ease;
}
.profile-photo-btn:hover {
  background: var(--rs-teal);
  color: var(--rs-space-950);
}

.rs-profile-card .card-title {
  color: var(--rs-space-800);
  font-weight: 700;
  font-size: 1.05rem;
  margin-bottom: 6px;
  text-align: center;
}
.rs-profile-card .card-text {
  font-size: 0.95rem;
  line-height: 1.9;
  text-align: center;
}
.rs-profile-card .card-body {
  padding: 20px 18px 24px;
}

.rs-intro {
  display: flow-root;
}
.rs-intro .rs-profile-float {
  margin-bottom: 1.25rem;
}
@media (min-width: 992px) {
  .rs-intro .rs-profile-float {
    float: left;
    width: 32%;
    margin: 0 2% 1.25rem 0;
  }
}
@media (min-width: 1200px) {
  .rs-intro .rs-profile-float {
    width: 26%;
    margin-right: 2.5%;
  }
}

/* ===== People page ===================================================== */

.rs-people-section {
  margin-top: 0.75rem;
}
.rs-people-card {
  border-radius: 14px;
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.rs-people-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--rs-shadow);
}
.rs-people-photo {
  display: block;
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
  object-position: center top;
  background: var(--rs-space-900);
}
.rs-people-body {
  padding: 8px 6px 10px;
  text-align: center;
}
.rs-people-name {
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--rs-space-800);
  overflow-wrap: anywhere;
}
.rs-people-role {
  font-size: 0.78rem;
  color: var(--rs-muted);
  margin-top: 2px;
  overflow-wrap: anywhere;
}

/* ===== Section headings =============================================== */

.rs-main p strong {
  color: var(--rs-space-800);
}

.container p strong font[size="4"],
.container p strong font[size="5"] {
  color: var(--rs-space-800);
  letter-spacing: 0.03em;
}

/* Section labels such as "Biography", "Work Experience" */
.rs-main .container p > strong {
  font-weight: 700;
}

/* ===== Publication / list content ===================================== */

.rs-main ul {
  padding-left: 1.4rem;
}
.rs-main ul li {
  margin-bottom: 0.55rem;
}
.rs-main ul li p {
  margin-bottom: 0.35rem;
}
.rs-main em {
  font-style: italic;
}

.rs-main font[color="red"] {
  color: #d93535;
}
.rs-main font[color="green"] {
  color: var(--rs-teal-600);
}

/* ===== News page ======================================================= */

.container #News p,
.container #News_cn p {
  position: relative;
  padding: 12px 18px 12px 26px;
  background: var(--rs-paper);
  border: 1px solid var(--rs-line);
  border-left: 4px solid var(--rs-teal);
  border-radius: 10px;
  box-shadow: var(--rs-shadow-sm);
  margin-bottom: 10px;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.container #News p:hover,
.container #News_cn p:hover {
  transform: translateX(3px);
  box-shadow: var(--rs-shadow);
}

/* ===== Footer ========================================================== */

.rs-footer {
  margin-top: 56px;
  padding: 22px 0;
  color: rgba(255, 255, 255, 0.82);
  background: linear-gradient(160deg, var(--rs-space-950) 0%, var(--rs-space-900) 60%, var(--rs-space-800) 100%);
  border-top: 1px solid rgba(45, 212, 191, 0.3);
}
.rs-footer-legal {
  font-weight: 500;
}
.rs-footer-legal a {
  color: var(--rs-teal);
}
.rs-footer-meta {
  font-family: var(--rs-mono);
  font-size: 0.82rem;
  letter-spacing: 0.04em;
  color: rgba(45, 212, 191, 0.75);
}

/* ===== Responsive ====================================================== */

@media (max-width: 767.98px) {
  .rs-hero {
    padding: 44px 0 40px;
  }
}