/* ============================================================
   GTA.Plus · 公共基础样式（所有页面引用）
   ============================================================ */

:root {
  --brand:       #1f6feb;
  --brand-dark:  #0b4fbe;
  --brand-soft:  #e8f1ff;
  --text:        #1f2733;
  --text-soft:   #5b6675;
  --text-cell:   #33405a;
  --line:        #e4eaf2;
  --line-strong: #d5deea;
  --panel:       #ffffff;
  --page:        #f2f5fa;
  --stripe:      #f8fafd;
  --head-from:   #24334d;
  --head-to:     #16223a;
}

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

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

body {
  margin: 0;
  padding: 40px clamp(16px, 3.5vw, 56px) 72px;
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB",
               "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text);
  background-color: var(--page);
  background-image:
    radial-gradient(1200px 520px at 0% -12%, rgba(31, 111, 235, .10), transparent 60%),
    radial-gradient(900px 440px at 100% 0%, rgba(56, 189, 248, .10), transparent 55%);
  background-repeat: no-repeat;
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

::selection { background: rgba(31, 111, 235, .22); }

/* ---------------- 标题 ---------------- */

h1 {
  margin: 0 0 4px;
  font-size: clamp(26px, 3.2vw, 38px);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: .06em;
  color: #12203a;
  background: linear-gradient(120deg, #12203a 8%, #1f6feb 58%, #38bdf8 96%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

h1::after {
  content: "";
  display: block;
  width: 88px;
  height: 5px;
  margin: 14px 0 0;
  border-radius: 999px;
  background: linear-gradient(90deg, #1f6feb, #38bdf8 55%, rgba(56, 189, 248, 0));
}

h2, h3 { color: #16223a; }

h3 {
  margin: 48px 0 16px;
  padding-left: 16px;
  font-size: clamp(18px, 2vw, 22px);
  font-weight: 700;
  line-height: 1.4;
  border-left: 5px solid var(--brand);
}

h4 {
  display: flex;
  align-items: center;
  gap: 9px;
  margin: 30px 0 10px;
  font-size: 16px;
  font-weight: 700;
  color: var(--brand-dark);
}

h4::before {
  content: "";
  flex: none;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--brand);
  box-shadow: 0 0 0 3px rgba(31, 111, 235, .16);
}

/* ---------------- 正文 ---------------- */

p { margin: 10px 0; color: var(--text); }

b, strong { font-weight: 700; color: #16223a; }

a {
  color: var(--brand);
  text-decoration: none;
  padding: 0 1px;
  border-bottom: 1px solid rgba(31, 111, 235, .35);
  border-radius: 3px;
  transition: color .18s ease, background-color .18s ease, border-color .18s ease;
}

a:hover {
  color: var(--brand-dark);
  border-bottom-color: var(--brand-dark);
  background-color: rgba(31, 111, 235, .08);
}

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

hr {
  height: 1px;
  margin: 56px 0;
  border: 0;
  background: linear-gradient(90deg,
              transparent,
              var(--line-strong) 18%,
              var(--line-strong) 82%,
              transparent);
}

/* ---------------- 页面结尾署名块 ---------------- */

body > p:last-of-type {
  margin-top: 22px;
  padding: 14px 20px;
  color: var(--text-soft);
  font-size: 14px;
  background: var(--brand-soft);
  border-left: 4px solid var(--brand);
  border-radius: 0 10px 10px 0;
}

/* ---------------- 滚动条 ---------------- */

::-webkit-scrollbar { width: 12px; height: 12px; }
::-webkit-scrollbar-track { background: #eef2f8; }
::-webkit-scrollbar-thumb {
  background: #c3cedd;
  border: 3px solid #eef2f8;
  border-radius: 999px;
}
::-webkit-scrollbar-thumb:hover { background: #a8b7cb; }

/* ---------------- 响应式（基础） ---------------- */

@media (max-width: 900px) {
  body { padding: 26px 12px 52px; font-size: 14px; }
  h3 { margin-top: 36px; }
  hr { margin: 40px 0; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}