:root {
  --brand: #5b6cff;
  --brand-2: #8a5bff;
  --brand-3: #ff6b9d;
  --brand-glow: rgba(91, 108, 255, 0.35);
  --ink: #1f2333;
  --ink-soft: #3a3f52;
  --muted: #5c6272;
  --line: #e6e8f0;
  --bg: #f7f8fc;
  --bg-soft: #eef0f8;
  --card: #ffffff;
  --card-glass: rgba(255, 255, 255, 0.72);
  --shadow-sm: 0 2px 12px rgba(20, 24, 50, 0.05);
  --shadow-md: 0 10px 30px rgba(20, 24, 50, 0.08);
  --shadow-lg: 0 18px 48px rgba(20, 24, 50, 0.12);
  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 22px;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --grad-brand: linear-gradient(135deg, #5b6cff 0%, #8a5bff 48%, #ff6b9d 100%);
}

body.dark {
  --ink: #e8eaf2;
  --ink-soft: #c5c9d6;
  --muted: #a3a8ba;
  --line: #2a2e3d;
  --bg: #12141c;
  --bg-soft: #171a24;
  --card: #1a1d28;
  --card-glass: rgba(26, 29, 40, 0.72);
  --shadow-sm: 0 2px 12px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 10px 30px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 18px 48px rgba(0, 0, 0, 0.5);
  --brand-glow: rgba(91, 108, 255, 0.45);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

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

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color 0.4s var(--ease), color 0.4s var(--ease);
}

a {
  color: var(--brand);
  text-decoration: none;
  transition: color 0.25s var(--ease), opacity 0.25s var(--ease);
}

a:hover {
  color: var(--brand-2);
}

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

::selection {
  background: var(--brand-glow);
  color: #fff;
}

:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
  border-radius: 4px;
}

.wrap {
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ===== Header ===== */
header.site {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--card-glass);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
  box-shadow: var(--shadow-sm);
  transition: background-color 0.4s var(--ease), border-color 0.4s var(--ease);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  gap: 16px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 18px;
  color: var(--ink);
  letter-spacing: 0.5px;
  transition: transform 0.3s var(--ease);
}

.logo:hover {
  transform: translateY(-1px);
  color: var(--ink);
}

.logo svg {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  transition: transform 0.45s var(--ease), box-shadow 0.45s var(--ease);
  box-shadow: 0 4px 14px var(--brand-glow);
}

.logo:hover svg {
  transform: rotate(-6deg) scale(1.06);
}

.nav ul {
  display: flex;
  gap: 22px;
  list-style: none;
  flex-wrap: wrap;
}

.nav ul a {
  color: var(--ink);
  font-size: 15px;
  position: relative;
  padding: 4px 0;
}

.nav ul a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 2px;
  border-radius: 2px;
  background: var(--grad-brand);
  transition: width 0.3s var(--ease);
}

.nav ul a:hover {
  color: var(--brand);
}

.nav ul a:hover::after {
  width: 100%;
}

.tools {
  display: flex;
  align-items: center;
  gap: 10px;
}

.search {
  display: flex;
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 4px 4px 4px 12px;
  background: var(--bg-soft);
  transition: border-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.search:focus-within {
  border-color: var(--brand);
  box-shadow: 0 0 0 3px var(--brand-glow);
}

.search input {
  border: none;
  outline: none;
  background: transparent;
  color: var(--ink);
  width: 130px;
  font-size: 14px;
  font-family: inherit;
}

.search input::placeholder {
  color: var(--muted);
}

.search button {
  border: none;
  background: var(--grad-brand);
  color: #fff;
  border-radius: 16px;
  padding: 5px 12px;
  cursor: pointer;
  font-size: 13px;
  font-family: inherit;
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.search button:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 16px var(--brand-glow);
}

.search button:active {
  transform: translateY(0);
}

.btn-icon {
  border: 1px solid var(--line);
  background: var(--card);
  color: var(--ink);
  border-radius: 20px;
  padding: 6px 14px;
  cursor: pointer;
  font-size: 13px;
  font-family: inherit;
  transition: all 0.3s var(--ease);
}

.btn-icon:hover {
  border-color: var(--brand);
  color: var(--brand);
  box-shadow: 0 4px 14px var(--brand-glow);
  transform: translateY(-1px);
}

.menu-btn {
  display: none;
  border: 1px solid var(--line);
  background: var(--card);
  color: var(--ink);
  border-radius: 8px;
  padding: 6px 10px;
  cursor: pointer;
  font-size: 16px;
  transition: all 0.3s var(--ease);
}

.menu-btn:hover {
  border-color: var(--brand);
  color: var(--brand);
}

/* ===== Hero ===== */
.hero {
  position: relative;
  overflow: hidden;
  color: #fff;
  padding: 56px 0 44px;
  background: var(--grad-brand);
  background-size: 200% 200%;
  animation: gradientShift 14s ease infinite;
}

.hero::before,
.hero::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  filter: blur(70px);
  pointer-events: none;
}

.hero::before {
  width: 380px;
  height: 380px;
  top: -140px;
  right: -80px;
  background: rgba(255, 107, 157, 0.55);
}

.hero::after {
  width: 320px;
  height: 320px;
  bottom: -160px;
  left: -60px;
  background: rgba(91, 108, 255, 0.6);
}

@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.hero .wrap {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 36px;
  align-items: center;
}

.hero h1 {
  font-size: 34px;
  line-height: 1.35;
  margin-bottom: 16px;
  font-weight: 800;
  letter-spacing: 0.5px;
  text-shadow: 0 2px 18px rgba(0, 0, 0, 0.12);
}

.hero p {
  font-size: 17px;
  opacity: 0.95;
  margin-bottom: 22px;
}

.hero .cta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.hero .cta a {
  padding: 11px 24px;
  border-radius: 24px;
  font-weight: 600;
  font-size: 15px;
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease), background-color 0.3s var(--ease);
}

.hero .cta .primary {
  background: #fff;
  color: #3d47c9;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.18);
}

.hero .cta .primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 14px 32px rgba(0, 0, 0, 0.26);
  color: #3d47c9;
}

.hero .cta .ghost {
  border: 1.5px solid rgba(255, 255, 255, 0.85);
  color: #fff;
  -webkit-backdrop-filter: blur(6px);
  backdrop-filter: blur(6px);
}

.hero .cta .ghost:hover {
  background: rgba(255, 255, 255, 0.16);
  transform: translateY(-3px);
  color: #fff;
}

.slider {
  background: rgba(255, 255, 255, 0.14);
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: var(--radius-lg);
  padding: 24px;
  -webkit-backdrop-filter: blur(12px) saturate(160%);
  backdrop-filter: blur(12px) saturate(160%);
  box-shadow: 0 18px 44px rgba(0, 0, 0, 0.16);
  transition: transform 0.4s var(--ease);
}

.slider:hover {
  transform: translateY(-4px);
}

.slider .slide {
  display: none;
  animation: fadeSlide 0.5s var(--ease);
}

.slider .slide.active {
  display: block;
}

@keyframes fadeSlide {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.slider h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.slider p {
  font-size: 14px;
  margin-bottom: 14px;
  opacity: 0.92;
}

.dots {
  display: flex;
  gap: 8px;
  margin-top: 8px;
}

.dots span {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.4);
  cursor: pointer;
  transition: background-color 0.3s var(--ease), transform 0.3s var(--ease);
}

.dots span:hover {
  transform: scale(1.3);
}

.dots span.on {
  background: #fff;
  transform: scale(1.15);
}

.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 34px;
}

.stat {
  background: rgba(255, 255, 255, 0.14);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius);
  padding: 16px;
  text-align: center;
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  transition: transform 0.35s var(--ease), background-color 0.35s var(--ease);
}

.stat:hover {
  transform: translateY(-4px);
  background: rgba(255, 255, 255, 0.22);
}

.stat b {
  font-size: 24px;
  display: block;
  font-weight: 800;
  letter-spacing: 0.5px;
}

.stat small {
  font-size: 12px;
  opacity: 0.85;
}

/* ===== Breadcrumb ===== */
.crumb {
  font-size: 13px;
  color: var(--muted);
  padding: 16px 0;
}

.crumb a {
  color: var(--muted);
}

.crumb a:hover {
  color: var(--brand);
}

/* ===== Sections ===== */
section {
  padding: 44px 0;
  scroll-margin-top: 80px;
}

section h2 {
  font-size: 26px;
  margin-bottom: 8px;
  color: var(--ink);
  line-height: 1.4;
  letter-spacing: 0.3px;
}

section h2 .tag {
  display: inline-block;
  font-size: 12px;
  background: rgba(91, 108, 255, 0.12);
  color: var(--brand);
  border-radius: 10px;
  padding: 2px 10px;
  vertical-align: middle;
  margin-right: 8px;
  font-weight: 600;
  letter-spacing: 1px;
}

body.dark section h2 .tag {
  background: rgba(91, 108, 255, 0.2);
}

section .lead {
  color: var(--muted);
  margin-bottom: 26px;
  font-size: 15px;
}

/* ===== Grid ===== */
.grid {
  display: grid;
  gap: 20px;
}

.g2 { grid-template-columns: repeat(2, 1fr); }
.g3 { grid-template-columns: repeat(3, 1fr); }
.g4 { grid-template-columns: repeat(4, 1fr); }

/* ===== Cards ===== */
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease), border-color 0.35s var(--ease);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: var(--grad-brand);
  opacity: 0;
  transition: opacity 0.35s var(--ease);
  pointer-events: none;
  z-index: 0;
}

.card > * {
  position: relative;
  z-index: 1;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
  border-color: transparent;
}

.card:hover::before {
  opacity: 0.04;
}

.card h3 {
  font-size: 18px;
  margin-bottom: 10px;
  color: var(--ink);
  line-height: 1.45;
}

.card h4 {
  font-size: 15px;
  margin: 14px 0 6px;
  color: var(--ink);
}

.card p {
  color: var(--muted);
  font-size: 14.5px;
}

.card ul {
  color: var(--muted);
  font-size: 14.5px;
  padding-left: 20px;
  margin-top: 8px;
}

.card ul li {
  margin-bottom: 6px;
}

.card ul li::marker {
  color: var(--brand);
}

.card a {
  font-weight: 600;
}

.card a:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ===== Article block ===== */
.article-block {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px;
  box-shadow: var(--shadow-sm);
}

.article-block h3 {
  font-size: 20px;
  margin: 24px 0 10px;
  color: var(--ink);
  padding-left: 14px;
  border-left: 4px solid var(--brand);
  line-height: 1.45;
}

.article-block h3:first-child {
  margin-top: 0;
}

.article-block h4 {
  font-size: 16px;
  margin: 16px 0 8px;
  color: var(--ink);
}

.article-block p {
  color: var(--ink-soft);
  font-size: 15px;
  margin-bottom: 10px;
}

.article-block ul,
.article-block ol {
  padding-left: 22px;
  color: var(--ink-soft);
  font-size: 15px;
  margin-bottom: 10px;
}

.article-block li {
  margin-bottom: 6px;
}

.article-block li::marker {
  color: var(--brand);
}

/* ===== News ===== */
.news-item {
  display: flex;
  gap: 16px;
  padding: 16px 0;
  border-bottom: 1px dashed var(--line);
  transition: transform 0.3s var(--ease), padding-left 0.3s var(--ease);
}

.news-item:hover {
  transform: translateX(4px);
  padding-left: 6px;
}

.news-item:last-child {
  border-bottom: none;
}

.news-item time {
  color: var(--muted);
  font-size: 13px;
  min-width: 92px;
  font-variant-numeric: tabular-nums;
}

.news-item h3 {
  font-size: 16px;
  margin-bottom: 4px;
  color: var(--ink);
  transition: color 0.25s var(--ease);
}

.news-item:hover h3 {
  color: var(--brand);
}

.news-item p {
  font-size: 14px;
  color: var(--muted);
}

/* ===== FAQ ===== */
.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  margin-bottom: 12px;
  overflow: hidden;
  background: var(--card);
  transition: border-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.faq-item:hover {
  border-color: var(--brand);
  box-shadow: 0 4px 16px var(--brand-glow);
}

.faq-item.open {
  border-color: var(--brand);
  box-shadow: 0 6px 22px var(--brand-glow);
}

.faq-q {
  width: 100%;
  text-align: left;
  background: transparent;
  border: none;
  padding: 16px 18px;
  font-size: 15.5px;
  font-weight: 600;
  color: var(--ink);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  font-family: inherit;
  transition: color 0.25s var(--ease);
}

.faq-q:hover {
  color: var(--brand);
}

.faq-a {
  padding: 0 18px 16px;
  color: var(--muted);
  font-size: 14.5px;
  display: none;
  animation: fadeSlide 0.35s var(--ease);
}

.faq-item.open .faq-a {
  display: block;
}

.faq-item.open .faq-q .arrow {
  transform: rotate(180deg);
}

.arrow {
  transition: transform 0.3s var(--ease);
  color: var(--brand);
  flex-shrink: 0;
}

/* ===== Steps ===== */
.steps {
  counter-reset: step;
  list-style: none;
  padding: 0;
}

.steps li {
  counter-increment: step;
  position: relative;
  padding-left: 52px;
  margin-bottom: 20px;
}

.steps li::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--grad-brand);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  box-shadow: 0 6px 16px var(--brand-glow);
  transition: transform 0.3s var(--ease);
}

.steps li:hover::before {
  transform: scale(1.1);
}

.steps h4 {
  font-size: 15.5px;
  color: var(--ink);
  margin-bottom: 4px;
}

.steps p {
  font-size: 14.5px;
  color: var(--muted);
}

/* ===== Author box ===== */
.author-box {
  display: flex;
  gap: 16px;
  align-items: center;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease);
}

.author-box:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.author-box .avatar {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--grad-brand);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 700;
  font-size: 20px;
  flex-shrink: 0;
  box-shadow: 0 6px 18px var(--brand-glow);
}

.author-box h4 {
  font-size: 16px;
  color: var(--ink);
}

.author-box p {
  font-size: 13.5px;
  color: var(--muted);
}

/* ===== Contact ===== */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.contact-item {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 18px;
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.contact-item:hover {
  transform: translateY(-3px);
  border-color: var(--brand);
  box-shadow: 0 8px 22px var(--brand-glow);
}

.contact-item h4 {
  font-size: 15px;
  color: var(--ink);
  margin-bottom: 6px;
}

.contact-item p {
  font-size: 14px;
  color: var(--muted);
  word-break: break-word;
}

/* ===== Sitemap ===== */
.sitemap-links {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.sitemap-links h4 {
  font-size: 15px;
  margin-bottom: 10px;
  color: var(--ink);
}

.sitemap-links ul {
  list-style: none;
  padding: 0;
}

.sitemap-links li {
  margin-bottom: 6px;
  font-size: 14px;
}

.sitemap-links a {
  color: var(--muted);
  position: relative;
  transition: color 0.25s var(--ease), padding-left 0.25s var(--ease);
}

.sitemap-links a::before {
  content: "›";
  position: absolute;
  left: -10px;
  opacity: 0;
  transition: opacity 0.25s var(--ease);
  color: var(--brand);
}

.sitemap-links a:hover {
  color: var(--brand);
  padding-left: 6px;
}

.sitemap-links a:hover::before {
  opacity: 1;
}

/* ===== Footer ===== */
footer.site {
  background: #141726;
  color: #a9aec2;
  padding: 44px 0 24px;
  margin-top: 30px;
}

footer.site .cols {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 28px;
  margin-bottom: 28px;
}

footer.site h4 {
  color: #fff;
  font-size: 15px;
  margin-bottom: 12px;
}

footer.site ul {
  list-style: none;
  padding: 0;
}

footer.site li {
  margin-bottom: 8px;
  font-size: 13.5px;
}

footer.site a {
  color: #a9aec2;
  transition: color 0.25s var(--ease), padding-left 0.25s var(--ease);
}

footer.site a:hover {
  color: #fff;
  padding-left: 4px;
}

footer.site .copy {
  border-top: 1px solid #262a3d;
  padding-top: 18px;
  font-size: 13px;
  text-align: center;
  color: #7d8296;
}

/* ===== Back to top ===== */
.backtop {
  position: fixed;
  right: 22px;
  bottom: 22px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--grad-brand);
  color: #fff;
  border: none;
  cursor: pointer;
  font-size: 18px;
  box-shadow: 0 6px 20px var(--brand-glow);
  display: none;
  z-index: 120;
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.backtop:hover {
  transform: translateY(-4px) scale(1.05);
  box-shadow: 0 12px 28px var(--brand-glow);
}

.backtop:active {
  transform: translateY(-1px) scale(1);
}

.backtop.show {
  display: block;
  animation: popIn 0.35s var(--ease);
}

@keyframes popIn {
  from { opacity: 0; transform: scale(0.6); }
  to { opacity: 1; transform: scale(1); }
}

/* ===== Scroll reveal ===== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
  will-change: opacity, transform;
}

.reveal.in {
  opacity: 1;
  transform: none;
}

/* ===== Reduced motion ===== */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* ===== Responsive: 960px ===== */
@media (max-width: 960px) {
  .hero .wrap {
    grid-template-columns: 1fr;
  }
  .g3,
  .g4 {
    grid-template-columns: repeat(2, 1fr);
  }
  .stats {
    grid-template-columns: repeat(2, 1fr);
  }
  .contact-grid,
  .sitemap-links {
    grid-template-columns: repeat(2, 1fr);
  }
  footer.site .cols {
    grid-template-columns: repeat(2, 1fr);
  }
  .article-block {
    padding: 24px;
  }
}

/* ===== Responsive: 680px ===== */
@media (max-width: 680px) {
  body {
    font-size: 15px;
  }
  .nav {
    height: 60px;
  }
  .nav ul {
    display: none;
  }
  .nav ul.open {
    display: flex;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    background: var(--card);
    flex-direction: column;
    padding: 16px 20px;
    border-bottom: 1px solid var(--line);
    gap: 14px;
    box-shadow: var(--shadow-md);
    animation: fadeSlide 0.3s var(--ease);
  }
  .nav ul.open a::after {
    display: none;
  }
  .menu-btn {
    display: block;
  }
  .search input {
    width: 90px;
  }
  .search button {
    padding: 4px 10px;
  }
  .hero {
    padding: 40px 0 36px;
  }
  .hero h1 {
    font-size: 26px;
  }
  .hero p {
    font-size: 15px;
  }
  .hero .cta a {
    padding: 10px 18px;
    font-size: 14px;
  }
  .slider {
    padding: 18px;
  }
  .stat b {
    font-size: 20px;
  }
  section {
    padding: 34px 0;
  }
  section h2 {
    font-size: 21px;
  }
  .g2,
  .g3,
  .g4 {
    grid-template-columns: 1fr;
  }
  .contact-grid,
  .sitemap-links {
    grid-template-columns: 1fr;
  }
  footer.site .cols {
    grid-template-columns: 1fr;
  }
  .article-block {
    padding: 20px;
  }
  .article-block h3 {
    font-size: 18px;
  }
  .news-item {
    flex-direction: column;
    gap: 4px;
  }
  .author-box {
    flex-direction: column;
    text-align: center;
    align-items: center;
  }
  .backtop {
    right: 14px;
    bottom: 14px;
    width: 42px;
    height: 42px;
  }
}

/* ===== Responsive: 400px ===== */
@media (max-width: 400px) {
  .wrap {
    padding: 0 14px;
  }
  .logo span {
    font-size: 16px;
  }
  .search input {
    width: 70px;
  }
  .hero h1 {
    font-size: 22px;
  }
  .stats {
    gap: 10px;
  }
  .stat {
    padding: 12px;
  }
}