/* ============================================================
   VPNCU · ai.css
   AI 工具加速专题页
   ============================================================ */

/* ---------- 页面 Hero ---------- */
.page-hero {
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  position: relative;
  overflow: hidden;
  padding: 56px 0 48px;
}

.page-hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--border) 1px, transparent 1px),
    linear-gradient(90deg, var(--border) 1px, transparent 1px);
  background-size: 48px 48px;
  opacity: .35;
  pointer-events: none;
}

.page-hero-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--gutter);
  position: relative;
  z-index: 1;
}

.page-hero .kicker {
  margin-bottom: 18px;
}

.page-hero h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(34px, 4vw, 52px);
  line-height: 1.12;
  letter-spacing: -.025em;
  color: var(--ink);
}

.page-hero h1 .accent-word {
  color: var(--accent-dark);
  background: linear-gradient(transparent 68%, rgba(25,173,146,.22) 68%);
  border-radius: 2px;
}

.page-hero .hero-sub {
  margin-top: 14px;
  max-width: 640px;
  font-size: 16px;
  color: var(--muted);
}

.page-hero .trust-row {
  margin-top: 20px;
}

.page-hero .tool-chips {
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.page-hero .tool-chips .chip {
  font-family: var(--font-mono);
  font-size: 12px;
}

/* ---------- 工具卡片 ---------- */
.tool-card-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.tool-card {
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  background: var(--panel);
  padding: 24px 26px;
  box-shadow: var(--shadow-1);
  transition: transform .22s ease, box-shadow .22s ease;
  min-width: 0;
}

.tool-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-2);
}

.tool-card-head {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
}

.tool-card-head .tool-icon {
  width: 36px;
  height: 36px;
  border-radius: 9px;
  background: var(--panel2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-dark);
  flex-shrink: 0;
}

.tool-card-head .tool-icon svg {
  width: 20px;
  height: 20px;
  display: block;
}

.tool-card-head .tool-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 17px;
  color: var(--ink);
}

.tool-card-head .tool-tag {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 10.5px;
  color: var(--accent-dark);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--r-pill);
  padding: 3px 10px;
  white-space: nowrap;
  max-width: 100%;
  overflow: hidden;
}

.tool-card-body p {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.7;
  margin-bottom: 12px;
}

.tool-card-body ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.tool-card-body li {
  padding: 5px 0;
  font-size: 13.5px;
  color: var(--muted);
  display: flex;
  align-items: flex-start;
  gap: 8px;
}

.tool-card-body li::before {
  content: '▸';
  color: var(--accent);
  font-size: 11px;
  flex-shrink: 0;
  margin-top: 2px;
}

.tool-card-body li strong {
  color: var(--ink);
  font-weight: 600;
}

/* ---------- 对照表 ---------- */
.compare-table .data-table td {
  font-size: 13px;
}

.compare-table .data-table th {
  font-size: 12.5px;
}

/* ---------- 开发者 / 双栏卡片 ---------- */
.dev-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.dev-card {
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  background: var(--panel);
  padding: 22px 24px;
  min-width: 0;
}

.dev-card .dev-cap {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--accent-dark);
  text-transform: uppercase;
  margin-bottom: 10px;
}

.dev-card h3 {
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 8px;
}

.dev-card p {
  font-size: 13.5px;
  color: var(--muted);
  line-height: 1.7;
}

/* ---------- 勾选清单 ---------- */
.check-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.check-list li {
  padding: 9px 0;
  font-size: 14.5px;
  color: var(--muted);
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

.check-list li::before {
  content: '✓';
  color: var(--ok);
  font-weight: 700;
  flex-shrink: 0;
}

.check-list li strong {
  color: var(--ink);
  font-weight: 600;
}

/* ---------- 失败现象列表 ---------- */
.fail-list {
  display: grid;
  gap: 10px;
}

.fail-item {
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  background: var(--panel);
  padding: 16px 20px;
}

.fail-item .fail-title {
  font-weight: 600;
  font-size: 14.5px;
  color: var(--ink);
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.fail-item .fail-title::before {
  content: '';
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--warn);
  flex-shrink: 0;
}

.fail-item p {
  font-size: 13.5px;
  color: var(--muted);
  line-height: 1.7;
}

/* ---------- 选线建议 CTA 链接 ---------- */
.cta-links {
  margin-top: 28px;
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
}

/* ---------- 底部 CTA 带 ---------- */
.cta-band {
  background: var(--accent-dark);
  border-radius: var(--r-lg);
  padding: 40px 44px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
  position: relative;
  overflow: hidden;
}

.cta-band::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: radial-gradient(circle, rgba(255,255,255,.08) 1px, transparent 1px);
  background-size: 22px 22px;
  pointer-events: none;
}

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

.cta-band .cta-title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 22px;
  color: var(--white);
  line-height: 1.3;
}

.cta-band .cta-sub {
  margin-top: 6px;
  font-size: 14px;
  color: rgba(255,255,255,.82);
  max-width: 480px;
}

.cta-band .btn-light {
  background: var(--white);
  color: var(--accent-dark);
  font-weight: 700;
  padding: 14px 30px;
  border-radius: 11px;
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-size: 15.5px;
  flex-shrink: 0;
  transition: background .18s ease, transform .18s ease;
}

.cta-band .btn-light:hover {
  background: var(--bg);
  transform: translateY(-1px);
}

.cta-band .btn-light .arr {
  width: 15px;
  height: 15px;
  display: block;
  flex-shrink: 0;
}

/* ---------- 响应式 ---------- */
@media (max-width: 900px) {
  .tool-card-grid {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 768px) {
  .page-hero {
    padding: 40px 0 36px;
  }

  .page-hero h1 {
    font-size: clamp(28px, 7vw, 36px);
  }

  .page-hero .hero-sub {
    font-size: 15px;
  }

  .cta-band {
    padding: 32px 28px;
    flex-direction: column;
    align-items: flex-start;
  }

  .cta-band .btn-light {
    width: 100%;
  }
}

@media (max-width: 480px) {
  .dev-grid {
    grid-template-columns: 1fr;
  }
}