/* ============================================================
   lji · 个人主页 v3 —— 明亮清爽 · 蓝调
   参考 image2:冷调近白背景 + 皇家蓝强调 + 高对比 + 品牌图标墙。
   内容仍以 AI 前置(多 agent / 自建 LLM 网关 / 自研 Skills)。
   ============================================================ */

:root {
  --bg:         #f7f9fe;
  --surface:    #ffffff;
  --ink:        #121a2f;   /* 近黑冷调标题(高对比) */
  --ink-soft:   #3f4b63;
  --muted:      #7f8aa3;
  --line:       #e3e8f1;
  --line-strong:#dfe6f2;
  --accent:     #4f78ea;   /* 皇家蓝 */
  --accent-2:   #5b86ee;
  --accent-ink: #2f54c8;
  --accent-bg:  #eaf0fd;
  --accent-soft:#f2f6fe;
  --shadow-sm:  0 4px 12px rgba(22,32,58,.06);
  --shadow:     0 1px 2px rgba(22,32,58,.05), 0 12px 30px rgba(40,64,140,.10);
  --shadow-lg:  0 2px 6px rgba(22,32,58,.07), 0 26px 54px rgba(40,64,140,.16);
  --shadow-blue:0 12px 24px rgba(79,120,234,.30);
  --radius:     16px;
  --maxw:       1120px;
  --sans: "Inter", -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: var(--sans);
  background: var(--bg);
  background-image: radial-gradient(55% 45% at 84% -8%, rgba(79,120,234,.07) 0%, transparent 60%),
                    radial-gradient(40% 35% at -2% 6%, rgba(79,120,234,.05) 0%, transparent 55%);
  color: var(--ink);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: inherit; text-decoration: none; }
::selection { background: var(--accent); color: #fff; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 5px; }
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 1.6rem; }

/* ============ 顶栏 ============ */
.nav { position: sticky; top: 0; z-index: 50; background: rgba(255,255,255,.86); backdrop-filter: saturate(180%) blur(14px); border-bottom: 1px solid transparent; transition: border-color .3s, box-shadow .3s; }
.nav.scrolled { border-bottom-color: var(--line); box-shadow: 0 10px 30px rgba(22,32,58,.06); }
.nav-inner { max-width: var(--maxw); margin: 0 auto; padding: .95rem 1.6rem; display: flex; align-items: center; justify-content: space-between; }
.brand { display: inline-flex; align-items: center; gap: .55rem; font-weight: 800; font-size: 1.12rem; letter-spacing: -.02em; }
.brand .mark { width: 26px; height: 26px; border-radius: 8px; background: linear-gradient(135deg, var(--accent-2), var(--accent)); color: #fff; display: grid; place-items: center; font-size: .82rem; font-weight: 800; box-shadow: var(--shadow-blue); }
.nav-links { display: flex; gap: 2rem; }
.nav-links a { color: var(--ink-soft); font-size: .92rem; font-weight: 500; transition: color .2s; }
.nav-links a:hover { color: var(--accent-ink); }
.nav-cta { font-size: .88rem; font-weight: 600; color: #fff; background: linear-gradient(135deg, var(--accent-2), var(--accent)); padding: .5rem 1rem; border-radius: 9px; box-shadow: var(--shadow-blue); transition: transform .15s, box-shadow .2s; }
.nav-cta:hover { transform: translateY(-1px); }
@media (max-width: 800px) { .nav-links { display: none; } }

/* ============ 通用 ============ */
section { padding: 6rem 0; }
.badge { display: inline-flex; align-items: center; gap: .5rem; font-size: .82rem; font-weight: 600; color: var(--accent-ink); background: var(--accent-bg); border: 1px solid #d9e4fb; padding: .4rem .85rem; border-radius: 999px; margin-bottom: 1.4rem; }
.badge .d { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 3px rgba(79,120,234,.18); }
.section-head { margin-bottom: 2.8rem; }
.kicker { display: inline-flex; align-items: center; gap: .55rem; font-size: .82rem; font-weight: 700; letter-spacing: .02em; color: var(--accent-ink); margin-bottom: .9rem; }
.kicker .sq { width: 16px; height: 16px; border-radius: 5px; background: linear-gradient(135deg, var(--accent-2), var(--accent)); box-shadow: var(--shadow-blue); }
.h2 { font-size: clamp(1.8rem, 3.7vw, 2.5rem); font-weight: 800; letter-spacing: -.03em; margin-bottom: .65rem; }
.h2 .accent { color: var(--accent); }
.lead { color: var(--ink-soft); max-width: 52ch; font-size: 1.04rem; }

/* ============ HERO ============ */
.hero { position: relative; padding: 3.6rem 0 4rem; overflow: hidden; }
.hero-deco { position: absolute; inset: 0; z-index: 0; pointer-events: none; background-image: radial-gradient(rgba(79,120,234,.12) 1.2px, transparent 1.4px); background-size: 24px 24px; -webkit-mask-image: radial-gradient(70% 60% at 18% 22%, #000 0%, transparent 62%); mask-image: radial-gradient(70% 60% at 18% 22%, #000 0%, transparent 62%); opacity: .7; }
.hero-grid { position: relative; z-index: 1; display: grid; grid-template-columns: 1.12fr 1fr; gap: 3rem; align-items: center; }
.hero h1 { font-size: clamp(2.3rem, 4.7vw, 3.4rem); font-weight: 800; line-height: 1.16; letter-spacing: -.035em; margin-bottom: 1.4rem; white-space: nowrap; }
.hero h1 .accent { color: var(--accent); }
.hero-sub { font-size: 1.12rem; color: var(--ink-soft); max-width: 44ch; margin-bottom: 2.1rem; }
.cta { display: flex; flex-wrap: wrap; gap: .9rem; margin-bottom: 2rem; }
.btn { display: inline-flex; align-items: center; gap: .5rem; padding: .82rem 1.5rem; border-radius: 12px; font-weight: 600; font-size: .96rem; cursor: pointer; transition: transform .16s cubic-bezier(.2,.7,.2,1), box-shadow .22s, border-color .2s, color .2s, background .2s; }
.btn svg { width: 18px; height: 18px; }
.btn-primary { color: #fff; background: linear-gradient(135deg, var(--accent-2), var(--accent)); box-shadow: var(--shadow-blue); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 16px 30px rgba(79,120,234,.42); }
.btn-primary:active { transform: translateY(0); }
.btn-ghost { color: var(--ink); background: var(--surface); border: 1px solid var(--line-strong); box-shadow: var(--shadow-sm); }
.btn-ghost:hover { transform: translateY(-2px); border-color: var(--accent); color: var(--accent-ink); box-shadow: var(--shadow); }
.hero-contact { display: flex; align-items: center; gap: 1rem; color: var(--muted); font-size: .9rem; }
.hero-contact a { display: inline-flex; align-items: center; gap: .4rem; color: var(--ink-soft); transition: color .2s; }
.hero-contact a:hover { color: var(--accent-ink); }
.hero-contact svg { width: 17px; height: 17px; }
@media (max-width: 880px) { .hero-grid { grid-template-columns: 1fr; gap: 2.4rem; } .hero-art { order: 2; max-width: 440px; margin: 0 auto; } }
@media (max-width: 480px) { .hero h1 { white-space: normal; font-size: 2.05rem; } }

/* 英雄插画 */
.hero-art { position: relative; }
.hero-art svg { width: 100%; height: auto; display: block; transform: scale(1.06); transform-origin: center; filter: drop-shadow(0 34px 54px rgba(40,64,140,.18)); }

/* ============ 关于 ============ */
.about-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.25rem; }
.feature { position: relative; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.8rem 1.6rem; box-shadow: var(--shadow); transition: transform .22s, box-shadow .22s, border-color .22s; }
.feature:hover { transform: translateY(-3px); border-color: var(--line-strong); box-shadow: var(--shadow-lg); }
.feature .ic { width: 48px; height: 48px; border-radius: 13px; background: linear-gradient(135deg, var(--accent-2), var(--accent)); color: #fff; display: grid; place-items: center; margin-bottom: 1.1rem; box-shadow: var(--shadow-blue); }
.feature .ic svg { width: 24px; height: 24px; }
.feature h3 { font-size: 1.08rem; font-weight: 750; margin-bottom: .5rem; }
.feature p { color: var(--ink-soft); font-size: .92rem; }
@media (max-width: 880px) { .about-grid { grid-template-columns: 1fr; } }

/* ============ 技术栈:品牌图标墙 ============ */
.alt { background: linear-gradient(180deg, #f7f9fe, #f6f8fc); }
.stack-group { margin-top: 1.6rem; }
.stack-group + .stack-group { margin-top: 1.6rem; }
.stack-group .gl { font-size: .82rem; font-weight: 700; color: var(--muted); letter-spacing: .03em; margin-bottom: .9rem; display: flex; align-items: center; gap: .55rem; }
.stack-group .gl::after { content: ""; flex: 1; height: 1px; background: var(--line); }
.pills { display: flex; flex-wrap: wrap; gap: .7rem; }
.pill { display: inline-flex; align-items: center; gap: .55rem; background: var(--surface); border: 1px solid var(--line); border-radius: 999px; padding: .5rem 1rem; font-size: .9rem; font-weight: 600; color: #25304a; box-shadow: var(--shadow-sm); transition: transform .16s, box-shadow .2s, border-color .2s; }
.pill:hover { transform: translateY(-3px); border-color: var(--line-strong); box-shadow: var(--shadow); }
.pill img { width: 20px; height: 20px; display: block; flex: none; }
.pill .mono { width: 20px; height: 20px; flex: none; border-radius: 6px; background: linear-gradient(135deg, #e9f0fd, #dde8fc); color: var(--accent-ink); font-size: .66rem; font-weight: 800; display: grid; place-items: center; line-height: 1; border: 1px solid #d7e3fb; }

/* ============ 项目 ============ */
.proj-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.25rem; }
.proj { position: relative; display: flex; flex-direction: column; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.7rem; box-shadow: var(--shadow); overflow: hidden; transition: transform .22s, box-shadow .22s, border-color .22s; }
.proj::after { content: ""; position: absolute; left: 0; right: 0; top: 0; height: 3px; background: linear-gradient(90deg, var(--accent-2), var(--accent)); transform: scaleX(0); transform-origin: left; transition: transform .3s ease; }
.proj:hover { transform: translateY(-3px); border-color: var(--line-strong); box-shadow: var(--shadow-lg); }
.proj:hover::after { transform: scaleX(1); }
.proj-top { display: flex; align-items: center; justify-content: space-between; margin-bottom: .9rem; }
.proj-kind { font-size: .74rem; font-weight: 700; letter-spacing: .04em; text-transform: uppercase; color: var(--accent-ink); background: var(--accent-bg); padding: .26rem .6rem; border-radius: 7px; }
.proj-idx { font-size: .82rem; font-weight: 800; color: var(--line-strong); }
.proj h3 { font-size: 1.15rem; font-weight: 760; margin-bottom: .55rem; letter-spacing: -.01em; }
.proj p { color: var(--ink-soft); font-size: .9rem; margin-bottom: 1.1rem; flex: 1; }
.proj .ptags { display: flex; flex-wrap: wrap; gap: .4rem; }
.proj .ptags span { font-size: .74rem; font-weight: 600; color: var(--ink-soft); background: var(--bg); border: 1px solid var(--line); padding: .2rem .55rem; border-radius: 6px; }
@media (max-width: 980px) { .proj-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 680px) { .proj-grid { grid-template-columns: 1fr; } }

/* ============ 联系 ============ */
.contact-card { display: grid; grid-template-columns: 1.2fr auto; gap: 2rem; align-items: center; background: linear-gradient(135deg, #3f6fe6, #5b86ee); color: #fff; border-radius: 18px; padding: 2.6rem; box-shadow: 0 24px 50px rgba(63,111,230,.32); }
.contact-card h2 { font-size: clamp(1.5rem, 3vw, 2rem); font-weight: 800; letter-spacing: -.02em; margin-bottom: .6rem; }
.contact-card p { color: rgba(255,255,255,.86); max-width: 46ch; }
.contact-btn { display: inline-flex; align-items: center; gap: .55rem; background: #fff; color: var(--accent-ink); font-weight: 700; padding: .9rem 1.5rem; border-radius: 12px; white-space: nowrap; box-shadow: 0 10px 24px rgba(0,0,0,.16); transition: transform .16s; }
.contact-btn:hover { transform: translateY(-2px); }
.contact-btn svg { width: 18px; height: 18px; }
@media (max-width: 720px) { .contact-card { grid-template-columns: 1fr; gap: 1.4rem; padding: 2rem; text-align: center; } .contact-btn { justify-content: center; } }

/* ============ 页脚 ============ */
.footer { border-top: 1px solid var(--line); padding: 2.6rem 0; }
.footer-inner { display: flex; flex-wrap: wrap; gap: .5rem 1.5rem; align-items: center; justify-content: space-between; color: var(--muted); font-size: .86rem; }
.footer .accent { color: var(--accent-ink); font-weight: 600; }

/* ============ 渐入 ============ */
.reveal { opacity: 0; transform: translateY(20px); transition: opacity .6s cubic-bezier(.2,.7,.2,1), transform .6s cubic-bezier(.2,.7,.2,1); }
.reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation: none !important; transition: none !important; } .reveal { opacity: 1; transform: none; } }