/* Base Theme Variables */
:root {
  --bg: #ffffff;
  --text: #111111;
  --muted: #666666;
  --border: #e5e5e5;
  --primary: #111111;
  --grid-line: #000000;
  --header-h: 60px;
}

[data-theme="dark"] {
  --bg: #0a0a0a;
  --text: #f5f5f5;
  --muted: #b0b0b0;
  --border: #222222;
  --primary: #ffffff;
  --grid-line: #ffffff;
}

/* Global Reset */
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  line-height: 1.6;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

.container {
  width: min(1200px, 92%);
  margin: 0 auto;
}

/* Header */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: var(--bg);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: var(--header-h);
  gap: 16px;
}

.header__logo {
  font-weight: 700;
  letter-spacing: .2px;
  font-size: 20px;
}

.header__actions { display: flex; align-items: center; gap: 10px; }

.theme-toggle {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: transparent;
  display: inline-grid;
  place-items: center;
  cursor: pointer;
}
.theme-toggle__icon {
  width: 18px; height: 18px; display: inline-block;
  background: conic-gradient(from 0deg, var(--primary) 0 180deg, transparent 180deg 360deg);
  border-radius: 50%;
  -webkit-mask: radial-gradient(circle at 60% 40%, black 55%, transparent 56%);
          mask: radial-gradient(circle at 60% 40%, black 55%, transparent 56%);
}

.lang { position: relative; display: inline-flex; align-items: center; }
.lang__toggle {
  height: 36px; padding: 0 10px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: transparent; color: var(--text);
  font-size: 12px; cursor: pointer;
}
.lang__menu {
  position: absolute; right: 0; top: calc(100% + 6px);
  min-width: calc(140px / 3);
  width: calc(140px / 3); /* 2. 缩小为当前的 1/3 */
  border: 1px solid var(--border);
  background: var(--bg);
  border-radius: 10px;
  box-shadow: 0 6px 24px color-mix(in oklab, var(--text) 10%, transparent);
  padding: 6px;
  z-index: 200;
}
.lang__item {
  width: 100%; text-align: center; /* 2. 窄宽度下居中更协调 */
  height: 32px; padding: 0 10px;
  background: transparent; color: var(--text);
  border: 0; border-radius: 8px;
  cursor: pointer; font-size: 12px;
}
.lang__item:hover { background: color-mix(in oklab, var(--text) 6%, var(--bg)); }

/* Layout spacing to avoid overlap with fixed header */
.main { padding-top: var(--header-h); padding-bottom: 0; }

/* Hero */
.hero {
  position: relative;
  height: 100vh;
  overflow: hidden;
}
.hero__bg {
  position: absolute; inset: 0;
  display: grid; place-items: center;
}
.hero__content {
  position: absolute; inset: 0;
  display: grid; place-items: center;
  text-align: center;
}
.hero__title {
  margin: 0;
  transform: translateY(-100px);
  font-size: clamp(28px, 6vw, 64px);
  font-weight: 800;
  letter-spacing: .5px;
}

/* Retro Grid effect */
.retro-grid {
  aspect-ratio: 16 / 9;
  height: 100vh;
  width: calc(100vh * 16 / 9);
  --grid-color: var(--grid-line);
  background:
    radial-gradient(120% 60% at 50% 140%, var(--bg) 10%, transparent 60%),
    linear-gradient(to bottom, color-mix(in oklab, var(--bg) 0%, transparent) 0%, var(--bg) 80%),
    repeating-linear-gradient(
      to right,
      transparent 0 48px,
      color-mix(in oklab, var(--grid-color) 55%, transparent) 48px 49px,
      transparent 49px 96px
    ),
    repeating-linear-gradient(
      to top,
      transparent 0 48px,
      color-mix(in oklab, var(--grid-color) 55%, transparent) 48px 49px,
      transparent 49px 96px
    );
  transform: perspective(600px) rotateX(60deg);
  transform-origin: center top;
  animation: gridMove 10s linear infinite;
}

@keyframes gridMove {
  0% { background-position: 0 0, 0 0, 0 0, 0 0; }
  100% { background-position: 0 0, 0 0, 0 96px, 0 96px; }
}

/* Portfolio */
.portfolio { min-height: 100vh; display: grid; align-items: center; margin-top: 150px; margin-bottom: 150px; }
.portfolio__grid {
  list-style: none; margin: 0; padding: 0;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 21px; /* 75% of previous 28px */
}
.portfolio__item { }
.card { display: grid; justify-items: center; text-align: center; gap: 10px; }
.card__thumb {
  width: 120px; height: 120px;
  border-radius: 999px;
  border: 2px solid var(--text);
  display: grid; place-items: center;
  background: color-mix(in oklab, var(--text) 6%, var(--bg));
  color: var(--muted);
  font-weight: 700;
}
.card__title { font-weight: 600; }
.card__desc { color: var(--muted); font-size: 14px; }

/* Footer */
.footer {
  position: static;
  margin-top: 250px;
  background: var(--bg);
}
.footer__text { margin: 12px 0; font-size: 12px; text-align: center; color: var(--muted); }

/* Responsive */
@media (max-width: 1280px) {
  .portfolio__grid { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 768px) {
  .portfolio__grid { grid-template-columns: repeat(2, 1fr); }
  .card__thumb { width: 100px; height: 100px; }
}
@media (max-width: 480px) {
  .portfolio__grid { grid-template-columns: 1fr; }
  .header__logo { font-size: 20px; }
  .theme-toggle, .lang__toggle { height: 32px; }
}

/* Overrides */
.lang__menu { left: 0; right: 0; min-width: 100%; width: 100%; }
.card__img { width: 100%; height: 100%; object-fit: contain; border-radius: inherit; }