/* ============================================================
   Agent WHY · agentwhy.cn
   简约大方 · 纯静态 · 无依赖
   ============================================================ */

/* ---------- 主题变量 ---------- */
:root {
  color-scheme: light;

  --bg: #fbfaf8;
  --bg-soft: #f2f0ec;
  --card: #ffffff;
  --text: #1a1c20;
  --text-2: #5d626c;
  --line: #e7e4de;

  --accent: #4f46e5;
  --accent-2: #9333ea;
  --grad: linear-gradient(120deg, var(--accent), var(--accent-2));

  --btn-inverse-bg: #1a1c20;
  --btn-inverse-fg: #fbfaf8;

  /* 导航终端图标（跟随明暗主题） */
  --icon-bg: #f7f7f4;
  --icon-bar: #e2e2dd;
  --icon-line: #c8c8c2;
  --icon-prompt: #26282d;

  --shadow-rest: 0 1px 2px rgba(23, 22, 20, 0.05);
  --shadow-lift: 0 18px 44px -14px rgba(23, 22, 20, 0.18);
}

[data-theme="dark"] {
  color-scheme: dark;

  --bg: #0f1013;
  --bg-soft: #17181d;
  --card: #14161a;
  --text: #eceded;
  --text-2: #9aa0ab;
  --line: #26282f;

  --accent: #818cf8;
  --accent-2: #c084fc;

  --btn-inverse-bg: #eceded;
  --btn-inverse-fg: #0f1013;

  /* 导航终端图标（跟随明暗主题） */
  --icon-bg: #26282d;
  --icon-bar: #3c3f46;
  --icon-line: #4a4d55;
  --icon-prompt: #e8eaf0;

  --shadow-rest: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-lift: 0 18px 44px -14px rgba(0, 0, 0, 0.55);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background-color 0.35s ease, color 0.35s ease;
}

::selection { background: var(--accent); color: #fff; }

img, svg { display: inline-block; vertical-align: middle; }
a { color: inherit; text-decoration: none; }

h1, h2, h3 {
  margin: 0;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.25;
}

p { margin: 0; }

.mono {
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas,
    "Liberation Mono", monospace;
}

.container {
  width: min(100% - 48px, 1080px);
  margin-inline: auto;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 6px;
}

/* 跳转链接（无障碍） */
.skip {
  position: fixed;
  top: -64px;
  left: 16px;
  z-index: 100;
  padding: 10px 18px;
  background: var(--accent);
  color: #fff;
  border-radius: 10px;
  font-size: 0.9rem;
  transition: top 0.25s ease;
}
.skip:focus { top: 12px; }

/* ---------- 顶部导航 ---------- */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  height: 64px;
  transition: background-color 0.3s ease, border-color 0.3s ease,
    backdrop-filter 0.3s ease;
  border-bottom: 1px solid transparent;
}

.nav.scrolled {
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  -webkit-backdrop-filter: saturate(1.6) blur(14px);
  backdrop-filter: saturate(1.6) blur(14px);
  border-bottom-color: var(--line);
}

.nav-inner {
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas,
    monospace;
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  white-space: nowrap;
}
.brand .why { color: var(--accent); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.92rem;
}

.nav-links a {
  padding: 8px 12px;
  border-radius: 10px;
  color: var(--text-2);
  white-space: nowrap;
  transition: color 0.2s ease, background-color 0.2s ease;
}
.nav-links a:hover { color: var(--text); background: var(--bg-soft); }

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: transparent;
  color: var(--text-2);
  cursor: pointer;
  transition: color 0.2s ease, border-color 0.2s ease,
    background-color 0.2s ease, transform 0.2s ease;
}
.icon-btn:hover {
  color: var(--text);
  border-color: var(--text-2);
  background: var(--bg-soft);
  transform: translateY(-1px);
}
.icon-btn svg { width: 17px; height: 17px; }

/* 主题图标随模式切换 */
[data-theme="light"] .icon-sun { display: none; }
[data-theme="dark"] .icon-moon { display: none; }

/* ---------- Hero ---------- */
.hero {
  position: relative;
  min-height: calc(100svh - 64px);
  margin-top: 64px;
  display: flex;
  align-items: center;
  overflow: hidden;
}

/* 噪点颗粒（胶片质感，配合极光） */
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='160' height='160'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2'/><feColorMatrix type='saturate' values='0'/></filter><rect width='100%25' height='100%25' filter='url(%23n)' opacity='0.05'/></svg>");
  pointer-events: none;
}

/* 极光渐变（品牌色光斑） */
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(760px 520px at 84% 14%, rgba(79, 70, 229, 0.14), transparent 68%),
    radial-gradient(680px 500px at 8% 90%, rgba(147, 51, 234, 0.11), transparent 68%),
    radial-gradient(480px 360px at 58% 55%, rgba(56, 189, 248, 0.05), transparent 70%);
  pointer-events: none;
}

[data-theme="dark"] .hero::after {
  background:
    radial-gradient(760px 520px at 84% 14%, rgba(129, 140, 248, 0.17), transparent 68%),
    radial-gradient(680px 500px at 8% 90%, rgba(192, 132, 252, 0.12), transparent 68%),
    radial-gradient(480px 360px at 58% 55%, rgba(56, 189, 248, 0.06), transparent 70%);
}

.hero-inner {
  position: relative;
  z-index: 1;
  max-width: 780px;
  padding: 96px 0 112px;
}

/* 巨型问号水印 */
.hero-mark {
  position: absolute;
  right: -3vw;
  top: 50%;
  transform: translateY(-50%);
  z-index: 0;
  font-size: min(44vw, 540px);
  font-weight: 800;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1.5px var(--line);
  user-select: none;
  pointer-events: none;
  animation: float 10s ease-in-out infinite;
}
@supports not (-webkit-text-stroke: 1px black) {
  .hero-mark { color: var(--bg-soft); }
}

@keyframes float {
  0%, 100% { transform: translateY(-50%); }
  50% { transform: translateY(calc(-50% - 18px)); }
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 0.85rem;
  color: var(--text-2);
  letter-spacing: 0.02em;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #34c98e;
  box-shadow: 0 0 0 0 rgba(52, 201, 142, 0.5);
  animation: pulse 2.4s ease-out infinite;
}
@keyframes pulse {
  0% { box-shadow: 0 0 0 0 rgba(52, 201, 142, 0.45); }
  70% { box-shadow: 0 0 0 10px rgba(52, 201, 142, 0); }
  100% { box-shadow: 0 0 0 0 rgba(52, 201, 142, 0); }
}

.hero-title {
  margin: 26px 0 22px;
  font-size: clamp(3rem, 8.5vw, 5.25rem);
  font-weight: 800;
  letter-spacing: -0.035em;
  line-height: 1.08;
}

.hero-title em {
  font-style: normal;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-sub {
  max-width: 560px;
  font-size: clamp(1.05rem, 2.2vw, 1.25rem);
  color: var(--text-2);
  line-height: 1.9;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 40px;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 12px 24px;
  border-radius: 12px;
  border: 1px solid transparent;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease,
    border-color 0.2s ease, background-color 0.2s ease, color 0.2s ease;
}
.btn svg { width: 16px; height: 16px; }

.btn-primary {
  background: var(--btn-inverse-bg);
  color: var(--btn-inverse-fg);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lift);
}

.btn-ghost {
  border-color: var(--line);
  color: var(--text);
  background: transparent;
}
.btn-ghost:hover {
  transform: translateY(-2px);
  border-color: var(--text-2);
  background: var(--bg-soft);
}

/* ---------- 区块通用 ---------- */
.section { padding: 108px 0 0; }
.section:last-of-type { padding-bottom: 40px; }

.eyebrow {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.8rem;
  letter-spacing: 0.14em;
  color: var(--accent);
  text-transform: uppercase;
}
.eyebrow::before {
  content: "";
  width: 28px;
  height: 1.5px;
  background: currentColor;
  opacity: 0.6;
}

.section h2 {
  margin: 14px 0 18px;
  font-size: clamp(1.65rem, 3.4vw, 2.1rem);
  font-weight: 750;
}

.section .lead {
  max-width: 640px;
  color: var(--text-2);
}

/* ---------- 关于 ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 56px;
  margin-top: 36px;
  align-items: start;
}

.about-text p + p { margin-top: 18px; }
.about-text .lead { color: var(--text); }
.about-text a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: opacity 0.2s ease;
}
.about-text a:hover { opacity: 0.75; }

/* 「现在」清单 */
.now-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--line);
  font-size: 0.92rem;
}
.now-list li {
  display: flex;
  gap: 16px;
  padding: 15px 2px;
  border-bottom: 1px solid var(--line);
  line-height: 1.65;
}
.now-list .k {
  flex: none;
  width: 76px;
  color: var(--accent);
  font-size: 0.8rem;
  letter-spacing: 0.04em;
  padding-top: 2px;
}
.now-list .v { color: var(--text-2); }

/* ---------- 项目卡片 ---------- */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px;
  margin-top: 40px;
}

.card {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 26px 26px 22px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow-rest);
  transition: transform 0.25s ease, box-shadow 0.25s ease,
    border-color 0.25s ease, background-color 0.35s ease;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lift);
  border-color: color-mix(in srgb, var(--accent) 32%, var(--line));
}

.card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.card h3 { font-size: 1.12rem; font-weight: 700; }

.card-arrow {
  color: var(--text-2);
  transition: transform 0.25s ease, color 0.25s ease;
}
.card:hover .card-arrow {
  transform: translate(3px, -3px);
  color: var(--accent);
}

.card p {
  color: var(--text-2);
  font-size: 0.93rem;
  line-height: 1.75;
  flex: 1;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
  margin: 4px 0 0;
  padding: 0;
}
.tags li {
  padding: 3px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 0.72rem;
  color: var(--text-2);
  letter-spacing: 0.02em;
}

/* ---------- 联系 ---------- */
.email-box {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 32px;
  padding: 8px 8px 8px 22px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--card);
  box-shadow: var(--shadow-rest);
  flex-wrap: wrap;
}

.email-box .addr {
  font-size: clamp(1rem, 2.6vw, 1.2rem);
  letter-spacing: 0.01em;
}

.copy-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  border: none;
  border-radius: 10px;
  background: var(--btn-inverse-bg);
  color: var(--btn-inverse-fg);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, opacity 0.2s ease;
}
.copy-btn:hover { transform: translateY(-1px); box-shadow: var(--shadow-lift); }
.copy-btn.copied { background: #1f9d70; color: #fff; }
.copy-btn svg { width: 15px; height: 15px; }
.copy-btn .i-check { display: none; }
.copy-btn.copied .i-copy { display: none; }
.copy-btn.copied .i-check { display: inline-block; }

.contact-links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 26px;
}

/* ---------- 页脚 ---------- */
.footer {
  margin-top: 108px;
  border-top: 1px solid var(--line);
  padding: 34px 0 44px;
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 10px;
  font-size: 0.85rem;
  color: var(--text-2);
}
.footer a:hover { color: var(--text); }

/* ---------- 入场动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.7s cubic-bezier(0.2, 0.6, 0.2, 1),
    transform 0.7s cubic-bezier(0.2, 0.6, 0.2, 1);
}
.reveal.in { opacity: 1; transform: none; }
.reveal.d1 { transition-delay: 0.08s; }
.reveal.d2 { transition-delay: 0.16s; }
.reveal.d3 { transition-delay: 0.24s; }

/* ---------- 404 ---------- */
.page-404 {
  min-height: 100svh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 120px 24px 60px;
}
.page-404 .code {
  font-size: clamp(4.5rem, 14vw, 7rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  line-height: 1.1;
}
.page-404 h1 { margin: 10px 0 14px; font-size: 1.5rem; }
.page-404 p { color: var(--text-2); margin-bottom: 30px; }

/* ---------- 响应式 ---------- */
@media (max-width: 820px) {
  .about-grid { grid-template-columns: 1fr; gap: 36px; }
  .hero-mark { font-size: 62vw; right: -12vw; opacity: 0.75; }
}

@media (max-width: 600px) {
  .container { width: min(100% - 40px, 1080px); }
  .brand { font-size: 0.95rem; gap: 8px; }
  .brand svg { width: 18px; height: 18px; }
  .nav-links { font-size: 0.85rem; gap: 2px; }
  .nav-links a { padding: 7px 7px; }
  .icon-btn { width: 34px; height: 34px; }
  .section { padding-top: 84px; }
  .footer { margin-top: 84px; }
  .hero-inner { padding: 72px 0 88px; }
  .email-box { width: 100%; justify-content: space-between; }
}

@media (max-width: 430px) {
  /* 极窄屏幕：隐藏导航里的 GitHub 图标（首屏与联系区仍有入口） */
  .nav-gh { display: none; }
  .nav-links a { padding: 7px 6px; }
}

/* ---------- 动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .reveal { opacity: 1; transform: none; }
}