/* ============================================================
   SK 技术博客 — 简洁技术博客风格
   原则：白底黑字 · 无渐变发光 · 单一强调色 · 文字优先
   ============================================================ */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
  --fg: #24292f;
  --fg-light: #57606a;
  --fg-faint: #8b949e;
  --line: #d0d7de;
  --line-light: #eaeef2;
  --accent: #0969da;
  --accent-bg: #f0f6ff;
  --bg: #ffffff;
  --bg-soft: #f6f8fa;
  --code-bg: #f6f8fa;
  --danger: #cf222e;
  --ok: #1a7f37;
}

html { -webkit-text-size-adjust: 100%; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--fg);
  background: var(--bg);
  font-size: 16px;
  line-height: 1.8;
}

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

/* ─── 顶部导航 ─── */
.site-header {
  border-bottom: 1px solid var(--line-light);
  background: var(--bg);
  position: sticky; top: 0; z-index: 50;
}
.header-inner {
  max-width: 860px; margin: 0 auto; padding: 0 16px;
  display: flex; align-items: center; gap: 20px; height: 56px;
}
.site-title { font-size: 17px; font-weight: 700; color: var(--fg); }
.site-title:hover { text-decoration: none; color: var(--accent); }
.main-nav { display: flex; gap: 16px; flex: 1; }
.main-nav a { color: var(--fg-light); font-size: 14px; }
.main-nav a:hover { color: var(--accent); text-decoration: none; }
.user-nav { display: flex; gap: 10px; align-items: center; font-size: 14px; }
.user-nav .btn-link { color: var(--accent); }
.user-nav .username { color: var(--fg-light); }

/* ─── 容器 ─── */
.container { max-width: 860px; margin: 0 auto; padding: 24px 16px 48px; }
.container.narrow { max-width: 520px; }

/* ─── 首页 hero 价值区（对外招揽）─── */
.hero {
  margin: 6px 0 22px; padding: 22px 0 18px; border-bottom: 1px solid var(--line-light);
}
.hero-title { font-size: 26px; font-weight: 700; margin-bottom: 10px; letter-spacing: .2px; }
.hero-title .hero-dot { color: var(--fg-faint); font-weight: 400; }
.hero-sub { font-size: 15px; color: var(--fg-light); line-height: 1.8; max-width: 640px; margin-bottom: 8px; }
.hero-author { font-size: 13px; color: var(--fg-faint); margin-bottom: 14px; }
.hero-cta { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin-bottom: 12px; }
.btn-hero {
  display: inline-flex; align-items: center; gap: 8px;
  background: var(--accent); color: #fff; padding: 10px 20px;
  border-radius: 8px; font-size: 15px; font-weight: 600;
  box-shadow: 0 2px 8px rgba(9,105,218,.25);
}
.btn-hero:hover { background: #0a5fc4; text-decoration: none; }
.btn-hero .hero-year { font-size: 12px; font-weight: 400; opacity: .85; }
.btn-hero-ghost {
  color: var(--accent); border: 1px solid var(--line); padding: 10px 20px;
  border-radius: 8px; font-size: 15px;
}
.btn-hero-ghost:hover { border-color: var(--accent); text-decoration: none; background: var(--accent-bg); }
.hero-legend { display: flex; flex-wrap: wrap; gap: 14px; font-size: 13px; color: var(--fg-light); }
.hero-legend .lg-mem { color: #b08800; }
.hero-legend .lg-sec { color: var(--danger); }

/* ─── 热门深度 ─── */
.hot { margin-bottom: 20px; }
.free-picks { margin-bottom: 20px; }
.section-title { font-size: 15px; font-weight: 700; color: var(--fg); margin-bottom: 10px; }
.hot-grid { display: flex; flex-direction: column; gap: 6px; }
.hot-item {
  display: flex; justify-content: space-between; align-items: baseline; gap: 12px;
  padding: 8px 12px; border: 1px solid var(--line-light); border-radius: 8px;
  font-size: 14px; background: var(--bg-soft);
}
.hot-item:hover { border-color: var(--accent); text-decoration: none; }
.hot-title { color: var(--fg); font-weight: 500; }
.hot-meta { color: var(--fg-faint); font-size: 12px; white-space: nowrap; }

/* ─── 搜索框 ─── */
.search-form { flex: 0 1 180px; }
.search-form input {
  width: 100%; padding: 6px 12px; font-size: 13px;
  border: 1px solid var(--line); border-radius: 16px; outline: none; background: var(--bg-soft);
}
.search-form input:focus { border-color: var(--accent); background: #fff; }
.nav-sub { color: var(--accent); font-weight: 600; }

/* ─── 首页文章流 ─── */
.cat-tabs { display: flex; flex-wrap: wrap; gap: 6px; margin: 8px 0 20px; }
.cat-tabs a {
  font-size: 13px; color: var(--fg-light); padding: 4px 12px;
  border: 1px solid var(--line); border-radius: 16px;
}
.cat-tabs a:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }
.cat-tabs a.active { background: var(--accent); border-color: var(--accent); color: #fff; }

.post-list { border-top: 1px solid var(--line-light); }
.post-item {
  padding: 18px 0; border-bottom: 1px solid var(--line-light);
}
.post-item h2 { font-size: 18px; font-weight: 600; margin-bottom: 6px; }
.post-item h2 a { color: var(--fg); }
.post-item h2 a:hover { color: var(--accent); text-decoration: none; }
.post-meta { font-size: 13px; color: var(--fg-faint); margin-bottom: 8px; display: flex; flex-wrap: wrap; gap: 12px; }
.post-meta .lock { color: var(--danger); }
.post-summary { font-size: 14px; color: var(--fg-light); line-height: 1.7; }
.post-tags { margin-top: 8px; }
.tag {
  font-size: 12px; color: var(--accent); background: var(--accent-bg);
  padding: 2px 8px; border-radius: 4px; margin-right: 6px;
}
.tag:hover { text-decoration: none; background: #dbe9ff; }

.pagination { display: flex; gap: 12px; margin-top: 24px; font-size: 14px; }

/* ─── 文章页 ─── */
.article { max-width: 760px; }
.article h1 { font-size: 26px; line-height: 1.4; margin-bottom: 10px; }
.article .post-meta { border-bottom: 1px solid var(--line-light); padding-bottom: 14px; margin-bottom: 20px; }
.article-body { font-size: 15.5px; }
.article-body h2 { font-size: 21px; margin: 28px 0 12px; padding-bottom: 6px; border-bottom: 1px solid var(--line-light); }
.article-body h3 { font-size: 17px; margin: 22px 0 8px; }
.article-body p { margin-bottom: 14px; }
.article-body ul, .article-body ol { margin: 0 0 14px 24px; }
.article-body li { margin-bottom: 4px; }
.article-body blockquote {
  border-left: 3px solid var(--line); padding: 2px 14px; color: var(--fg-light);
  margin: 0 0 14px; background: var(--bg-soft);
}
.article-body code {
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  font-size: 13.5px; background: var(--code-bg); padding: 2px 5px; border-radius: 4px;
}
.article-body pre {
  background: var(--code-bg); padding: 14px; border-radius: 6px;
  overflow-x: auto; margin: 0 0 14px; line-height: 1.6;
}
.article-body pre code { background: none; padding: 0; }
.article-body table { border-collapse: collapse; width: 100%; margin: 0 0 14px; font-size: 14px; }
.article-body th, .article-body td { border: 1px solid var(--line); padding: 7px 10px; text-align: left; }
.article-body th { background: var(--bg-soft); font-weight: 600; }
.article-body img { max-width: 100%; }

/* ─── 面包屑 & 相关文章 ─── */
.breadcrumb {
  font-size: 13px; color: #57606a; margin: 0 0 14px; padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}
.breadcrumb a { color: #0969da; text-decoration: none; }
.breadcrumb a:hover { text-decoration: underline; }
.related {
  margin-top: 28px; padding-top: 16px; border-top: 1px solid var(--line);
}
.related h3 { font-size: 15px; color: #24292f; margin-bottom: 10px; }
.related ul { list-style: none; }
.related li { padding: 6px 0; font-size: 14px; border-bottom: 1px dashed #eaeef2; }
.related li a { color: #0969da; text-decoration: none; }
.related li a:hover { text-decoration: underline; }

/* ─── 付费墙 ─── */
.cap-word {
  flex: 0 0 auto; padding: 6px 12px; border: 1px solid #d0d7de;
  border-radius: 6px; font-size: 14px; color: #24292f; background: #fff;
  white-space: nowrap; user-select: none;
}
.cap-marker { transition: left .05s; }

/* ─── 三色滑块验证弹窗（UX v2）─── */
.cap-modal-overlay {
  position: fixed; inset: 0; background: rgba(16, 22, 30, .55);
  z-index: 1000; display: none; align-items: center; justify-content: center;
  padding: 16px; backdrop-filter: blur(2px);
}
.cap-modal-overlay.show { display: flex; animation: capFadeIn .18s ease-out; }
.cap-modal-card {
  background: #fff; border-radius: 14px; padding: 26px 24px;
  max-width: 540px; width: 100%; box-shadow: 0 20px 60px rgba(0,0,0,.28);
  animation: capPopIn .22s cubic-bezier(.2,.9,.3,1.2);
}
@keyframes capFadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes capPopIn { from { opacity: 0; transform: scale(.92) translateY(8px); } to { opacity: 1; transform: scale(1) translateY(0); } }
@keyframes capShake {
  0%, 100% { transform: translateX(0); }
  20% { transform: translateX(-6px); } 40% { transform: translateX(6px); }
  60% { transform: translateX(-4px); } 80% { transform: translateX(4px); }
}
.cap-shake { animation: capShake .4s ease; }
.cap-hint { font-size: 13px; color: #8b949e; margin-top: 2px; }
.cap-hint.err { color: #cf222e; }

.cap-slider-row { display: flex; align-items: center; gap: 10px; margin-bottom: 16px; }
.cap-dot {
  width: 16px; height: 16px; border-radius: 50%; flex: 0 0 16px;
  box-shadow: inset 0 0 0 3px rgba(255,255,255,.35);
}
.cap-slider-row input[type="range"] {
  -webkit-appearance: none; appearance: none; flex: 1; height: 8px;
  border-radius: 4px; outline: none; cursor: pointer; touch-action: manipulation;
  background: linear-gradient(to right, var(--c) var(--val, 0%), #e8ecf0 var(--val, 0%), #e8ecf0 100%);
}
.cap-slider-row input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none; width: 26px; height: 26px;
  border-radius: 50%; background: #fff; border: 3px solid var(--c);
  box-shadow: 0 2px 6px rgba(0,0,0,.22); cursor: grab; transition: transform .12s ease;
}
.cap-slider-row input[type="range"]::-webkit-slider-thumb:active {
  transform: scale(1.18); cursor: grabbing;
}
.cap-slider-row input[type="range"]::-moz-range-thumb {
  width: 24px; height: 24px; border-radius: 50%; background: #fff;
  border: 3px solid var(--c); box-shadow: 0 2px 6px rgba(0,0,0,.22); cursor: grab;
}
.cap-progress {
  display: flex; align-items: center; gap: 6px; margin: 2px 0 16px;
}
.cap-progress .pdot {
  width: 10px; height: 10px; border-radius: 50%;
  border: 2px solid #d0d7de; background: transparent; transition: all .25s ease;
}
.cap-progress .pdot.on { border-color: var(--pc); background: var(--pc); }
.cap-progress .plabel { font-size: 12px; color: #8b949e; margin-left: 6px; }
.cap-btn-row { display: flex; justify-content: space-between; align-items: center; gap: 10px; }
.cap-btn-ghost {
  background: transparent; border: 1px solid #d0d7de; color: #57606a;
  border-radius: 8px; padding: 9px 16px; font-size: 14px; cursor: pointer;
  transition: all .15s ease;
}
.cap-btn-ghost:hover { background: #f6f8fa; border-color: #b6bec7; }
.cap-btn-ghost:active { transform: scale(.97); }
.cap-btn-primary {
  background: #0969da; color: #fff; border: none; border-radius: 8px;
  padding: 10px 22px; font-size: 14px; font-weight: 600; cursor: pointer;
  box-shadow: 0 2px 8px rgba(9,105,218,.3); transition: all .18s ease;
}
.cap-btn-primary:hover { background: #0a5fc4; }
.cap-btn-primary:active { transform: scale(.97); }
.cap-btn-primary:disabled { background: #b6bec7; box-shadow: none; cursor: not-allowed; }
@keyframes capPop { 0% { transform: scale(1); } 40% { transform: scale(1.12); } 100% { transform: scale(1); } }
.cap-pop { animation: capPop .3s ease; }
@keyframes capCheck { 0% { transform: scale(0); } 60% { transform: scale(1.2); } 100% { transform: scale(1); } }
.cap-check-ok { animation: capCheck .35s cubic-bezier(.2,.9,.3,1.4); display: inline-block; }
.protect-note {
  font-size: 12px; color: #8b949e; margin-bottom: 8px; text-align: right;
}
#canvas-wrap { -webkit-user-select: none; user-select: none; }
#canvas-wrap canvas { display: block; }
.paywall {
  border: 1px solid var(--line); border-radius: 8px; padding: 32px 24px;
  text-align: center; margin: 24px 0;
  background: var(--bg-soft);
  -webkit-user-select: none; user-select: none;
}
.paywall input, .paywall .btn { -webkit-user-select: text; user-select: text; }
.paywall .lock-icon { font-size: 30px; color: var(--fg-faint); margin-bottom: 10px; }
.paywall h3 { font-size: 18px; margin-bottom: 8px; }
.paywall p { font-size: 14px; color: var(--fg-light); margin-bottom: 16px; }
.paywall .price-note { font-size: 13px; color: var(--accent); margin-bottom: 16px; }
.btn {
  display: inline-block; padding: 8px 22px; border-radius: 6px; font-size: 14px;
  border: 1px solid var(--accent); background: var(--accent); color: #fff;
  cursor: pointer; text-align: center;
}
.btn:hover { background: #0a5bbf; text-decoration: none; }
.btn.secondary { background: #fff; color: var(--accent); }
.btn.secondary:hover { background: var(--accent-bg); }
.btn-block { display: block; width: 100%; }

/* ─── 表单 ─── */
.form-group { margin-bottom: 16px; }
.form-group label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 6px; }
.form-group input[type="text"],
.form-group input[type="password"],
.form-group input[type="email"] {
  width: 100%; padding: 9px 12px; border: 1px solid var(--line); border-radius: 6px;
  font-size: 15px; outline: none;
}
.form-group input:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(9,105,218,.12); }

/* ─── 消息 ─── */
.flashes { margin-bottom: 18px; }
.flash { padding: 10px 14px; border-radius: 6px; font-size: 14px; margin-bottom: 8px; }
.flash.ok { background: #dafbe1; color: var(--ok); }
.flash.warn { background: #fff8c5; color: #9a6700; }

/* ─── 订阅页 ─── */
.page-title { font-size: 24px; margin-bottom: 6px; }
.page-sub { color: var(--fg-light); font-size: 14px; margin-bottom: 24px; }
.plan-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; margin-bottom: 24px; }
.plan-card { border: 1px solid var(--line); border-radius: 8px; padding: 20px; text-align: center; }
.plan-card.hot { border-color: var(--accent); background: var(--accent-bg); }
.plan-name { font-size: 16px; font-weight: 700; }
.plan-price { font-size: 30px; font-weight: 700; margin: 10px 0 4px; color: var(--accent); }
.plan-price small { font-size: 13px; color: var(--fg-light); font-weight: 400; }
.plan-note { font-size: 13px; color: var(--fg-light); margin-bottom: 14px; }
.plan-redeem { border: 1px solid var(--line); border-radius: 8px; padding: 16px; margin-top: 16px; }

/* ─── 信息页 ─── */
.info-card { border: 1px solid var(--line-light); border-radius: 8px; padding: 20px; margin-bottom: 16px; }
.info-card h3 { font-size: 16px; margin-bottom: 10px; }

/* ─── 页脚 ─── */
.site-footer {
  border-top: 1px solid var(--line-light); padding: 20px 16px;
  text-align: center; color: var(--fg-faint); font-size: 13px;
}

/* ─── 移动端 ─── */
@media (max-width: 640px) {
  body { font-size: 15px; }
  .header-inner { gap: 10px; height: 50px; padding: 0 12px; }
  .site-title { font-size: 15px; }
  .main-nav { gap: 10px; }
  .main-nav a { font-size: 13px; }
  .search-form { flex: 0 1 100%; order: 5; margin: 4px 0 6px; }
  .article h1 { font-size: 21px; }
  .container { padding: 16px 14px 40px; }
  .plan-grid { grid-template-columns: 1fr 1fr; gap: 10px; }
  .plan-price { font-size: 24px; }
  /* 触控目标放大（≥40px） */
  .cat-tabs a { padding: 8px 14px; font-size: 14px; }
  .tag { padding: 5px 10px; font-size: 12.5px; margin-right: 8px; }
  .post-item h2 { line-height: 1.6; }
  .post-item { padding: 16px 0; }
  .post-meta { gap: 8px; }
  .btn-hero, .btn-hero-ghost { padding: 12px 20px; font-size: 15px; }
  .hot-item { padding: 10px 12px; }
  .hero-title { font-size: 22px; }
  .hero-author { font-size: 12.5px; }
  .hero-legend { gap: 8px; font-size: 12.5px; }
}