/* AI Nav — main stylesheet */

:root {
  --ai-bg: #0b1218;
  --ai-bg-elevated: #121c26;
  --ai-surface: #162230;
  --ai-border: rgba(140, 190, 210, 0.14);
  --ai-text: #e8f1f5;
  --ai-muted: #8aa3b3;
  --ai-accent: #2ec4b6;
  --ai-accent-2: #3d9cf0;
  --ai-accent-soft: rgba(46, 196, 182, 0.14);
  --ai-warn: #e8a54b;
  --ai-danger: #e07a7a;
  --ai-radius: 14px;
  --ai-shadow: 0 18px 50px rgba(0, 0, 0, 0.35);
  --ai-font: "Segoe UI", "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", sans-serif;
  --ai-display: "Trebuchet MS", "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --ai-max: 1180px;
  --ai-narrow: 760px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--ai-font);
  color: var(--ai-text);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(61, 156, 240, 0.18), transparent 55%),
    radial-gradient(900px 500px at 90% 0%, rgba(46, 196, 182, 0.14), transparent 50%),
    linear-gradient(180deg, #0b1218 0%, #0e1620 40%, #0b1218 100%);
  background-attachment: fixed;
  line-height: 1.6;
  min-height: 100vh;
}

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

a {
  color: var(--ai-accent);
  text-decoration: none;
}

a:hover {
  color: #5ee0d2;
}

.screen-reader-text,
.skip-link {
  position: absolute;
  left: -9999px;
}

.skip-link:focus {
  left: 1rem;
  top: 1rem;
  z-index: 100;
  background: var(--ai-accent);
  color: #04201c;
  padding: 0.5rem 0.75rem;
}

.ai-container {
  width: min(100% - 2rem, var(--ai-max));
  margin-inline: auto;
}

.ai-container--narrow {
  width: min(100% - 2rem, var(--ai-narrow));
}

/* Header */
.ai-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(16px);
  background: rgba(11, 18, 24, 0.82);
  border-bottom: 1px solid var(--ai-border);
}

.ai-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 72px;
}

.ai-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: inherit;
}

.ai-brand:hover {
  color: inherit;
}

.ai-brand__mark {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background:
    linear-gradient(135deg, var(--ai-accent), var(--ai-accent-2));
  box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.08), 0 8px 24px rgba(46, 196, 182, 0.35);
  animation: ai-pulse 3.5s ease-in-out infinite;
}

.ai-brand__text {
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
}

.ai-brand__text strong {
  font-family: var(--ai-display);
  font-size: 1.05rem;
  letter-spacing: -0.02em;
}

.ai-brand__text small {
  color: var(--ai-muted);
  font-size: 0.75rem;
}

.ai-nav__list,
.ai-mobile-nav__list,
.ai-footer__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 1.25rem;
}

.ai-nav__list a,
.ai-mobile-nav__list a,
.ai-footer__list a {
  color: var(--ai-muted);
  font-weight: 500;
}

.ai-nav__list a:hover,
.ai-mobile-nav__list a:hover {
  color: var(--ai-text);
}

.ai-nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--ai-border);
  border-radius: 10px;
  background: transparent;
  cursor: pointer;
}

.ai-nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 4px auto;
  background: var(--ai-text);
}

.ai-mobile-nav {
  border-top: 1px solid var(--ai-border);
  padding: 1rem 1.25rem 1.25rem;
}

.ai-mobile-nav__list {
  flex-direction: column;
}

@media (max-width: 840px) {
  .ai-nav {
    display: none;
  }
  .ai-nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
  }
}

/* Hero */
.ai-hero {
  position: relative;
  padding: clamp(3.5rem, 8vw, 6.5rem) 0 clamp(2.5rem, 5vw, 4rem);
  overflow: hidden;
}

.ai-hero__bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(120deg, transparent 30%, rgba(46, 196, 182, 0.06) 50%, transparent 70%),
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='80' height='80'%3E%3Cpath d='M0 80V0h80' fill='none' stroke='rgba(140,190,210,0.06)' stroke-width='1'/%3E%3C/svg%3E");
  pointer-events: none;
  animation: ai-drift 18s linear infinite;
}

.ai-hero__content {
  position: relative;
  max-width: 720px;
}

.ai-hero__brand {
  margin: 0 0 0.75rem;
  font-family: var(--ai-display);
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  background: linear-gradient(90deg, #dff8f4, var(--ai-accent), var(--ai-accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  animation: ai-fade-up 0.7s ease both;
}

.ai-hero__title {
  margin: 0 0 0.85rem;
  font-family: var(--ai-display);
  font-size: clamp(1.35rem, 3vw, 1.85rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--ai-text);
  animation: ai-fade-up 0.7s ease 0.08s both;
}

.ai-hero__desc {
  margin: 0 0 1.5rem;
  color: var(--ai-muted);
  font-size: 1.05rem;
  max-width: 36em;
  animation: ai-fade-up 0.7s ease 0.16s both;
}

.ai-search {
  display: flex;
  gap: 0.5rem;
  padding: 0.4rem;
  border-radius: 999px;
  background: rgba(22, 34, 48, 0.9);
  border: 1px solid var(--ai-border);
  box-shadow: var(--ai-shadow);
  animation: ai-fade-up 0.7s ease 0.24s both;
}

.ai-search input {
  flex: 1;
  border: 0;
  background: transparent;
  color: var(--ai-text);
  font: inherit;
  padding: 0.85rem 1.1rem;
  outline: none;
}

.ai-search button {
  border: 0;
  border-radius: 999px;
  padding: 0.85rem 1.4rem;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  color: #04201c;
  background: linear-gradient(135deg, var(--ai-accent), #4fd4c8);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.ai-search button:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 20px rgba(46, 196, 182, 0.35);
}

/* Sections */
.ai-section {
  padding: 2.5rem 0 3.5rem;
}

.ai-section__head {
  margin-bottom: 1.5rem;
}

.ai-section__head h1,
.ai-section__head h2 {
  margin: 0 0 0.4rem;
  font-family: var(--ai-display);
  font-size: clamp(1.35rem, 2.5vw, 1.75rem);
  letter-spacing: -0.02em;
}

.ai-section__head p {
  margin: 0;
  color: var(--ai-muted);
}

/* Filters */
.ai-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin-bottom: 1.5rem;
}

.ai-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  border: 1px solid var(--ai-border);
  background: rgba(22, 34, 48, 0.65);
  color: var(--ai-muted);
  border-radius: 999px;
  padding: 0.45rem 0.9rem;
  font: inherit;
  font-size: 0.92rem;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}

.ai-chip:hover {
  color: var(--ai-text);
  border-color: rgba(46, 196, 182, 0.35);
}

.ai-chip.is-active {
  color: #04201c;
  background: var(--ai-accent);
  border-color: transparent;
  font-weight: 600;
}

.ai-chip__count {
  opacity: 0.7;
  font-size: 0.8em;
}

/* Layout */
.ai-layout {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 1.5rem;
  align-items: start;
}

@media (max-width: 960px) {
  .ai-layout {
    grid-template-columns: 1fr;
  }
}

/* Tool cards */
.ai-tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1rem;
}

.ai-tool-grid--featured .ai-tool-card {
  border-color: rgba(46, 196, 182, 0.28);
}

.ai-tool-card {
  display: flex;
  gap: 0.9rem;
  padding: 1rem;
  border-radius: var(--ai-radius);
  background: linear-gradient(160deg, rgba(22, 34, 48, 0.95), rgba(14, 22, 32, 0.9));
  border: 1px solid var(--ai-border);
  color: inherit;
  transition: transform 0.22s ease, border-color 0.22s ease, box-shadow 0.22s ease;
  min-height: 118px;
}

.ai-tool-card:hover {
  color: inherit;
  transform: translateY(-3px);
  border-color: rgba(46, 196, 182, 0.4);
  box-shadow: 0 14px 36px rgba(0, 0, 0, 0.28);
}

.ai-tool-card__icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: 12px;
  overflow: hidden;
  background: var(--ai-accent-soft);
}

.ai-tool-card__icon img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.ai-tool-card__body {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  min-width: 0;
}

.ai-tool-card__title {
  font-weight: 650;
  font-size: 1.02rem;
  letter-spacing: -0.01em;
}

.ai-tool-card__desc {
  color: var(--ai-muted);
  font-size: 0.88rem;
  line-height: 1.45;
}

.ai-tool-card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  margin-top: auto;
}

.ai-tool-card__tags span {
  font-size: 0.72rem;
  color: var(--ai-accent);
  background: var(--ai-accent-soft);
  padding: 0.15rem 0.45rem;
  border-radius: 999px;
}

/* Side panel */
.ai-side-panel {
  padding: 1.15rem;
  border-radius: var(--ai-radius);
  background: var(--ai-surface);
  border: 1px solid var(--ai-border);
  margin-bottom: 1rem;
}

.ai-side-panel h3 {
  margin: 0 0 0.75rem;
  font-size: 1rem;
}

.ai-side-panel ul {
  margin: 0;
  padding-left: 1.1rem;
  color: var(--ai-muted);
  font-size: 0.92rem;
}

.ai-side-panel li + li {
  margin-top: 0.35rem;
}

.ai-side-panel--cta {
  text-align: center;
}

.ai-side-panel--cta p {
  margin: 0 0 0.85rem;
  color: var(--ai-muted);
}

/* Buttons */
.ai-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.75rem 1.2rem;
  border-radius: 999px;
  font: inherit;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}

.ai-btn--primary {
  background: linear-gradient(135deg, var(--ai-accent), #4fd4c8);
  color: #04201c;
}

.ai-btn--primary:hover {
  color: #04201c;
  transform: translateY(-1px);
}

.ai-btn--ghost {
  background: transparent;
  border-color: var(--ai-border);
  color: var(--ai-text);
}

.ai-btn--ghost:hover {
  border-color: rgba(46, 196, 182, 0.45);
  color: var(--ai-text);
}

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

.ai-load-more-wrap {
  display: flex;
  justify-content: center;
  margin-top: 1.5rem;
}

/* Blog */
.ai-blog-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1rem;
}

.ai-blog-item a {
  display: block;
  padding: 1.15rem;
  border-radius: var(--ai-radius);
  background: var(--ai-surface);
  border: 1px solid var(--ai-border);
  color: inherit;
  height: 100%;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.ai-blog-item a:hover {
  transform: translateY(-2px);
  border-color: rgba(61, 156, 240, 0.4);
  color: inherit;
}

.ai-blog-item h3 {
  margin: 0 0 0.5rem;
  font-size: 1.05rem;
}

.ai-blog-item p {
  margin: 0 0 0.75rem;
  color: var(--ai-muted);
  font-size: 0.9rem;
}

.ai-blog-item time {
  color: var(--ai-muted);
  font-size: 0.8rem;
}

/* Detail */
.ai-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  align-items: center;
  color: var(--ai-muted);
  font-size: 0.88rem;
  margin: 1.5rem 0 1.25rem;
}

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

.ai-detail__hero {
  display: flex;
  justify-content: space-between;
  gap: 1.5rem;
  align-items: flex-start;
  padding: 1.5rem;
  border-radius: calc(var(--ai-radius) + 4px);
  background:
    linear-gradient(135deg, rgba(46, 196, 182, 0.1), transparent 40%),
    var(--ai-surface);
  border: 1px solid var(--ai-border);
  margin-bottom: 1.75rem;
}

.ai-detail__identity {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
}

.ai-detail__icon {
  width: 72px;
  height: 72px;
  border-radius: 18px;
  object-fit: cover;
  background: var(--ai-accent-soft);
}

.ai-detail__title {
  margin: 0 0 0.4rem;
  font-family: var(--ai-display);
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  letter-spacing: -0.03em;
}

.ai-detail__excerpt {
  margin: 0 0 0.85rem;
  color: var(--ai-muted);
  max-width: 40em;
}

.ai-detail__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.ai-detail__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  flex-shrink: 0;
}

.ai-badge {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.6rem;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 600;
  background: var(--ai-accent-soft);
  color: var(--ai-accent);
}

.ai-badge--muted {
  background: rgba(138, 163, 179, 0.15);
  color: var(--ai-muted);
}

.ai-badge--link {
  background: rgba(61, 156, 240, 0.14);
  color: var(--ai-accent-2);
}

.ai-detail__grid {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 1.5rem;
  align-items: start;
  margin-bottom: 2.5rem;
}

@media (max-width: 900px) {
  .ai-detail__hero {
    flex-direction: column;
  }
  .ai-detail__grid {
    grid-template-columns: 1fr;
  }
}

.ai-detail__block {
  margin-bottom: 1.75rem;
  padding: 1.25rem 1.35rem;
  border-radius: var(--ai-radius);
  background: rgba(18, 28, 38, 0.72);
  border: 1px solid var(--ai-border);
}

.ai-detail__block h2 {
  margin: 0 0 0.85rem;
  font-size: 1.15rem;
  font-family: var(--ai-display);
}

.ai-detail__compare {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
}

@media (max-width: 700px) {
  .ai-detail__compare {
    grid-template-columns: 1fr;
  }
}

.ai-list {
  margin: 0;
  padding-left: 1.15rem;
  color: var(--ai-muted);
}

.ai-list li + li {
  margin-top: 0.4rem;
}

.ai-list--pros li::marker {
  color: var(--ai-accent);
}

.ai-list--cons li::marker {
  color: var(--ai-danger);
}

.ai-prose {
  color: var(--ai-muted);
}

.ai-prose h2,
.ai-prose h3,
.ai-prose strong {
  color: var(--ai-text);
}

.ai-prose a {
  text-decoration: underline;
  text-underline-offset: 2px;
}

.ai-prose img {
  border-radius: 12px;
  margin: 1rem 0;
}

.ai-related {
  padding-bottom: 3rem;
}

.ai-related h2 {
  font-family: var(--ai-display);
  margin: 0 0 1rem;
}

/* Article */
.ai-article {
  padding: 2rem 0 3.5rem;
}

.ai-article__head {
  margin-bottom: 1.5rem;
}

.ai-article__head h1 {
  margin: 0 0 0.5rem;
  font-family: var(--ai-display);
  font-size: clamp(1.6rem, 3vw, 2.2rem);
}

.ai-article__head time {
  color: var(--ai-muted);
}

/* Ads */
.ai-ad {
  margin: 1rem auto;
  width: min(100% - 2rem, var(--ai-max));
  min-height: 0;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow: hidden;
}

.ai-ad--sidebar,
.ai-layout__side .ai-ad,
.ai-detail__side .ai-ad {
  width: 100%;
  margin: 0 0 1rem;
}

.ai-ad--home_mid {
  grid-column: 1 / -1;
  width: 100%;
  margin: 0.25rem 0;
  padding: 0.75rem;
  border-radius: var(--ai-radius);
  border: 1px dashed var(--ai-border);
  background: rgba(18, 28, 38, 0.5);
}

/* Footer */
.ai-footer {
  border-top: 1px solid var(--ai-border);
  padding: 2.5rem 0 2rem;
  margin-top: 1rem;
  background: rgba(8, 12, 16, 0.55);
}

.ai-footer__inner {
  display: grid;
  gap: 1.25rem;
}

.ai-footer__brand strong {
  font-family: var(--ai-display);
  font-size: 1.1rem;
}

.ai-footer__brand p,
.ai-footer__copy {
  color: var(--ai-muted);
  margin: 0.4rem 0 0;
  font-size: 0.92rem;
}

.ai-empty {
  color: var(--ai-muted);
  grid-column: 1 / -1;
  padding: 2rem;
  text-align: center;
  border: 1px dashed var(--ai-border);
  border-radius: var(--ai-radius);
}

/* Pagination */
.navigation.pagination {
  margin-top: 2rem;
}

.navigation.pagination .nav-links {
  display: flex;
  gap: 0.5rem;
  justify-content: center;
  flex-wrap: wrap;
}

.navigation.pagination a,
.navigation.pagination .current {
  padding: 0.45rem 0.8rem;
  border-radius: 8px;
  border: 1px solid var(--ai-border);
  color: var(--ai-muted);
}

.navigation.pagination .current {
  background: var(--ai-accent-soft);
  color: var(--ai-accent);
}

/* Animations */
@keyframes ai-fade-up {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes ai-pulse {
  0%,
  100% {
    box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.08), 0 8px 24px rgba(46, 196, 182, 0.3);
  }
  50% {
    box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.12), 0 10px 28px rgba(61, 156, 240, 0.4);
  }
}

@keyframes ai-drift {
  from {
    background-position: 0 0, 0 0;
  }
  to {
    background-position: 80px 80px, 0 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }
}