/* ============================================================
   styles.css · 杨金川个人简历网站
   风格：安静工艺（Quiet Craft）—— 暖纸底色、墨色文字、
        单一深绿点缀、编辑感排版
   ============================================================ */

:root {
  --paper: #f7f5f0;
  --paper-alt: #f0ede4;
  --ink: #1d1e1b;
  --muted: #65685e;
  --line: #e1ddd3;
  --accent: #1f6a56;
  --accent-deep: #15483a;
  --accent-soft: #dfe9e2;
  --white: #fffdf8;

  --font-serif: "Songti SC", "STSong", "SimSun", "Noto Serif SC", "Source Han Serif SC", serif;
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", sans-serif;

  --sp-1: 0.625rem;  /* 10px */
  --sp-2: 1rem;      /* 16px */
  --sp-3: 1.625rem;  /* 26px */
  --sp-4: 2.75rem;   /* 44px */
  --sp-5: 4.75rem;   /* 76px */

  --radius: 10px;
  --nav-h: 64px;
  --shadow: 0 1px 0 rgba(29, 30, 27, .06), 0 12px 32px -18px rgba(29, 30, 27, .25);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 12px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; display: block; }
a { color: var(--accent-deep); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { text-decoration: underline; }

.container {
  width: min(960px, calc(100% - 48px));
  margin-inline: auto;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--accent);
  color: var(--white);
  padding: 8px 16px;
  z-index: 100;
}
.skip-link:focus { left: 0; text-decoration: none; }

/* ---------- 导航 ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--nav-h);
  background: rgba(247, 245, 240, .86);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  width: min(960px, calc(100% - 40px));
  margin-inline: auto;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 24px;
}
.nav-brand {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: .04em;
  margin-right: auto;
}
.nav-brand span { color: var(--accent); }
.nav-links {
  display: flex;
  gap: 22px;
}
.nav-links a {
  position: relative;
  color: var(--muted);
  text-decoration: none;
  font-size: .92rem;
  padding: 4px 0;
  transition: color .2s;
}
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .25s ease;
}
.nav-links a:hover { color: var(--ink); }
.nav-links a:hover::after { transform: scaleX(1); }
.nav-links a.active { color: var(--accent); }
.nav-links a.active::after { transform: scaleX(1); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 22px;
  border-radius: 999px;
  font-size: .9rem;
  line-height: 1.5;
  text-decoration: none;
  border: 1px solid transparent;
  transition: all .2s ease;
  white-space: nowrap;
}
.btn-sm { padding: 6px 16px; font-size: .85rem; }
.btn-solid {
  background: var(--accent);
  color: var(--white);
}
.btn-solid:hover { background: var(--accent-deep); text-decoration: none; }
.btn-ghost {
  border-color: var(--line);
  color: var(--ink);
  background: transparent;
}
.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent-deep);
  text-decoration: none;
}

.nav .btn-solid { flex-shrink: 0; }

/* 移动端汉堡按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  padding: 8px;
  background: none;
  border: none;
  cursor: pointer;
}
.nav-toggle span {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--ink);
  transition: transform .25s ease, opacity .2s ease;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: clamp(72px, 12vh, 128px) 0 clamp(64px, 9vh, 104px);
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}
.hero-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(to right, rgba(29, 30, 27, .045) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(29, 30, 27, .045) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 90% 80% at 70% 20%, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse 90% 80% at 70% 20%, #000 30%, transparent 75%);
}
.hero-watermark {
  position: absolute;
  right: clamp(8px, 6vw, 96px);
  top: clamp(-20px, -2vw, 8px);
  font-family: var(--font-serif);
  font-size: clamp(13rem, 34vw, 26rem);
  line-height: 1;
  color: transparent;
  background: linear-gradient(160deg, rgba(31, 106, 86, .10), rgba(31, 106, 86, .02));
  -webkit-background-clip: text;
  background-clip: text;
  user-select: none;
}
.hero-inner { position: relative; }
.eyebrow {
  margin: 0 0 22px;
  font-size: .86rem;
  letter-spacing: .08em;
  color: var(--accent-deep);
  font-weight: 600;
}
.eyebrow::before {
  content: "";
  display: inline-block;
  width: 28px;
  height: 2px;
  background: var(--accent);
  vertical-align: middle;
  margin-right: 10px;
}
.hero-name {
  margin: 0 0 10px;
  font-family: var(--font-serif);
  font-size: clamp(3.4rem, 9.5vw, 6rem);
  line-height: 1.08;
  letter-spacing: .06em;
  color: var(--ink);
}
.hero-tagline {
  margin: 0 0 20px;
  font-size: clamp(1.05rem, 2.4vw, 1.35rem);
  color: var(--accent-deep);
  font-weight: 600;
  max-width: 30em;
}
.hero-desc {
  margin: 0 0 26px;
  color: var(--muted);
  max-width: 34em;
  font-size: .98rem;
}
.hero-tags {
  list-style: none;
  margin: 0 0 32px;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.hero-tags li {
  font-size: .8rem;
  color: var(--accent-deep);
  background: var(--accent-soft);
  border: 1px solid transparent;
  padding: 5px 14px;
  border-radius: 999px;
  letter-spacing: .02em;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

/* ---------- 通用 section ---------- */
.section { padding: clamp(64px, 9vw, 104px) 0; }
.section-alt { background: var(--paper-alt); }
.section-quote { background: var(--accent-deep); color: var(--paper); }

.section-head {
  display: flex;
  align-items: baseline;
  gap: 18px;
  margin-bottom: clamp(32px, 5vw, 52px);
  border-bottom: 1px solid var(--line);
  padding-bottom: 18px;
}
.section-num {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  color: var(--accent);
  font-weight: 700;
}
.section-title {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 3.4vw, 2.1rem);
  margin: 0;
  font-weight: 700;
  letter-spacing: .04em;
}

/* ---------- 关于 ---------- */
.about-body p {
  margin: 0 0 1.1em;
  max-width: 40em;
  font-size: 1.02rem;
}
.about-body strong { color: var(--accent-deep); font-weight: 600; }

/* ---------- 教育 ---------- */
.edu-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(24px, 4vw, 40px);
  box-shadow: var(--shadow);
}
.edu-main {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 20px;
  margin-bottom: 22px;
}
.edu-school { margin: 0; font-family: var(--font-serif); font-size: 1.5rem; }
.edu-meta { margin: 0; color: var(--muted); font-size: .95rem; }
.edu-time {
  margin: 0;
  margin-left: auto;
  color: var(--accent-deep);
  font-size: .92rem;
  font-weight: 600;
  white-space: nowrap;
}
.label {
  display: inline-block;
  font-size: .8rem;
  letter-spacing: .08em;
  color: var(--accent-deep);
  margin-bottom: 10px;
  font-weight: 600;
}
.course-tags {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.course-tags li {
  font-size: .85rem;
  background: var(--paper-alt);
  border: 1px solid var(--line);
  padding: 4px 12px;
  border-radius: 6px;
  color: var(--ink);
}

/* ---------- 项目 ---------- */
.project {
  background: var(--white);
  border: 1px solid var(--line);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius);
  padding: clamp(22px, 3.6vw, 34px);
  margin-bottom: 26px;
  transition: transform .25s ease, box-shadow .25s ease;
}
.project:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow);
}
.project-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px 20px;
  margin-bottom: 14px;
}
.project-name {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 1.3rem;
  letter-spacing: .02em;
}
.project-role {
  margin: 2px 0 0;
  color: var(--muted);
  font-size: .88rem;
}
.project-time {
  margin-left: auto;
  color: var(--accent-deep);
  font-size: .88rem;
  font-weight: 600;
  white-space: nowrap;
}
.project-points {
  margin: 0 0 16px;
  padding-left: 1.2em;
  color: var(--ink);
  font-size: .96rem;
}
.project-points li { margin-bottom: 6px; }
.project-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.project-tags span {
  font-size: .78rem;
  color: var(--accent-deep);
  background: var(--accent-soft);
  padding: 3px 10px;
  border-radius: 999px;
}

/* ---------- 经历（时间线） ---------- */
.timeline {
  position: relative;
  padding-left: 34px;
}
.timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: linear-gradient(to bottom, var(--accent), rgba(31, 106, 86, .15));
}
.timeline-item { position: relative; }
.timeline-dot {
  position: absolute;
  left: -34px;
  top: 10px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--paper-alt);
  border: 4px solid var(--accent);
}
.timeline-head {
  margin-bottom: 14px;
  display: flex;
  flex-wrap: wrap;
  gap: 2px 18px;
  align-items: baseline;
}
.timeline-title { margin: 0; font-family: var(--font-serif); font-size: 1.3rem; }
.timeline-org { margin: 0; color: var(--muted); font-size: .95rem; }
.timeline-time {
  margin: 0;
  margin-left: auto;
  color: var(--accent-deep);
  font-size: .88rem;
  font-weight: 600;
  white-space: nowrap;
}
.timeline-points {
  margin: 0;
  padding-left: 1.2em;
  font-size: .96rem;
}
.timeline-points li { margin-bottom: 6px; }

/* ---------- 能力 ---------- */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.skill-card {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 24px;
  transition: transform .25s ease, box-shadow .25s ease;
}
.skill-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow);
}
.skill-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: 10px;
  background: var(--accent);
  color: var(--white);
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 18px;
}
.skill-name {
  margin: 0 0 10px;
  font-family: var(--font-serif);
  font-size: 1.12rem;
}
.skill-desc {
  margin: 0;
  font-size: .92rem;
  color: var(--muted);
  line-height: 1.75;
}

/* ---------- 优势 ---------- */
.section-quote .section-head { border-bottom-color: rgba(247, 245, 240, .18); }
.section-quote .section-num { color: #9fd3bd; }
.section-quote .section-title { color: var(--paper); }
.strength-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}
.strength-item {
  background: rgba(255, 253, 248, .06);
  border: 1px solid rgba(247, 245, 240, .16);
  border-radius: var(--radius);
  padding: 22px 24px;
  font-size: .98rem;
  line-height: 1.8;
}
.strength-mark {
  color: #9fd3bd;
  margin-right: 10px;
  font-weight: 700;
}

/* ---------- 联系 ---------- */
.contact { text-align: center; }
.contact-title {
  font-family: var(--font-serif);
  font-size: clamp(1.7rem, 4.4vw, 2.6rem);
  font-weight: 600;
  line-height: 1.5;
  margin: 0 0 36px;
}
.contact-title em {
  font-style: normal;
  color: var(--accent-deep);
  border-bottom: 3px solid var(--accent);
  padding-bottom: 2px;
}
.contact-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 14px;
  margin-bottom: 22px;
}
.contact-meta { margin: 0; color: var(--muted); font-size: .92rem; }

/* ---------- 页脚 ---------- */
.footer {
  border-top: 1px solid var(--line);
  padding: 26px 0;
  background: var(--paper-alt);
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 10px;
  font-size: .86rem;
  color: var(--muted);
}
.footer a { color: var(--muted); }

/* ---------- 入场动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity .7s ease, transform .7s ease;
}
.reveal.in { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .project, .skill-card { transition: none; }
}

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

@media (max-width: 760px) {
  .nav-links {
    position: absolute;
    top: var(--nav-h);
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
    padding: 8px 24px 16px;
    display: none;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 12px 0; border-bottom: 1px solid var(--line); }
  .nav-links a::after { display: none; }
  .nav-toggle { display: flex; }
  .nav .btn-solid { display: none; }
  .container { width: min(960px, calc(100% - 36px)); }
  .edu-time, .project-time, .timeline-time { margin-left: 0; }
  .hero-watermark { opacity: .6; }
}