/* CSS Variables for European minimal style */
:root {
  --bg: #0b0d12;
  --bg-alt: #0f1219;
  --text: #e7e9ee;
  --muted: #a6adbb;
  --primary: #7aa2f7;
  --primary-600: #6790e8;
  --card: #121621;
  --border: #1f2533;
  --container: 1200px;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(0,0,0,.4);
}

* { box-sizing: border-box; }
html, body { height: 100%; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: ui-sans-serif, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji";
  background: radial-gradient(1000px 600px at 80% -10%, rgba(122,162,247,.12), transparent 60%), var(--bg);
  color: var(--text);
  line-height: 1.6;
}

.container { width: min(100% - 2rem, var(--container)); margin-inline: auto; }

.skip-link {
  position: absolute; left: -9999px; top: -9999px;
}
.skip-link:focus { left: 1rem; top: 1rem; background: var(--card); padding: .5rem .75rem; border-radius: .5rem; }

/* Header */
.site-header { position: sticky; top: 0; z-index: 100; background: rgba(11,13,18,.7); backdrop-filter: saturate(140%) blur(10px); border-bottom: 1px solid var(--border); }
.header-inner { display: flex; align-items: center; justify-content: space-between; padding: .75rem 0; }
.brand { display: inline-flex; align-items: center; gap: .6rem; color: var(--text); text-decoration: none; }
.brand-text { font-weight: 600; letter-spacing: .02em; }

.nav { display: flex; align-items: center; gap: 1rem; }
.menu { list-style: none; display: flex; gap: 1.2rem; margin: 0; padding: 0; }
.menu a { color: var(--muted); text-decoration: none; padding: .5rem .25rem; border-radius: .4rem; }
.menu a:hover, .menu a:focus { color: var(--text); }

.nav-toggle { display: none; background: none; border: 0; padding: .25rem; cursor: pointer; }
.nav-toggle-bar { display: block; width: 26px; height: 2px; background: var(--text); margin: 5px 0; border-radius: 2px; transition: transform .3s ease; }

/* Hero */
.hero { position: relative; isolation: isolate; }
.hero-inner { padding: 10svh 0 14svh; text-align: center; }
.hero-title { font-size: clamp(2rem, 3.8vw, 3.2rem); line-height: 1.2; letter-spacing: .01em; margin: 0 0 1rem; }
.hero-subtitle { color: var(--muted); margin: 0 auto 1.5rem; max-width: 70ch; }
.hero-cta { display: flex; gap: .8rem; justify-content: center; }
.hero-bg { position: absolute; inset: 0; background: radial-gradient(900px 500px at 20% 10%, rgba(122,162,247,.12), transparent 60%); z-index: -1; }

.btn { display: inline-flex; align-items: center; justify-content: center; gap: .5rem; padding: .8rem 1.1rem; border-radius: .7rem; text-decoration: none; font-weight: 600; letter-spacing: .01em; border: 1px solid var(--border); }
.btn-primary { background: linear-gradient(180deg, var(--primary), var(--primary-600)); color: #0b0d12; border: 0; box-shadow: var(--shadow); }
.btn-primary:hover { filter: brightness(.95); }
.btn-ghost { color: var(--text); background: transparent; }
.btn-ghost:hover { background: rgba(255,255,255,.04); }

/* Focus styles */
:where(a, button, .btn):focus-visible { outline: 2px solid color-mix(in oklab, var(--primary), white 10%); outline-offset: 2px; box-shadow: 0 0 0 6px rgba(122,162,247,.15); }

/* Sections */
.section { padding: 5rem 0; }
.section { scroll-margin-top: 72px; }
.section-alt { background: var(--bg-alt); border-block: 1px solid var(--border); }
.section-title { font-size: clamp(1.4rem, 2.2vw, 2rem); margin: 0 0 1rem; }
.content p { margin: .5rem 0 0; color: var(--muted); }

.grid { display: grid; gap: 1rem; }
.cards { grid-template-columns: repeat(12, 1fr); }
.card { grid-column: span 12; background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); padding: 1.2rem; box-shadow: 0 6px 20px rgba(0,0,0,.25); }
.card h3 { margin: .2rem 0 .5rem; font-size: 1.05rem; }
.card p { color: var(--muted); }

.features { grid-template-columns: repeat(12, 1fr); padding: 0; list-style: none; margin: 0; }
.feature { grid-column: span 12; background: transparent; border: 1px dashed var(--border); border-radius: var(--radius); padding: 1.2rem; }
.feature h3 { margin: .2rem 0 .5rem; font-size: 1.05rem; }
.feature p { color: var(--muted); }

/* Contact */
.contact address, .contact p { margin: .25rem 0; color: var(--muted); }
.contact a { color: var(--primary); text-underline-offset: 2px; }

/* Footer */
.site-footer { border-top: 1px solid var(--border); background: rgba(11,13,18,.8); }
.footer-inner { display: flex; gap: 1rem; align-items: center; justify-content: space-between; padding: 1.2rem 0; }
.footer-inner p { margin: 0; color: var(--muted); }
.footer-mail { color: var(--muted); text-decoration: none; }
.footer-mail:hover { color: var(--text); }
.beian { color: var(--muted); text-decoration: none; }
.beian:hover { color: var(--text); text-decoration: underline; }

/* Reveal animation */
[data-reveal] { opacity: 0; transform: translateY(8px); transition: opacity .6s ease, transform .6s ease; }
[data-reveal].is-visible { opacity: 1; transform: translateY(0); }

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

/* Responsive */
@media (min-width: 680px) {
  .cards .card { grid-column: span 6; }
  .features .feature { grid-column: span 4; }
}
@media (min-width: 980px) {
  .cards .card { grid-column: span 4; }
}

/* Mobile nav */
@media (max-width: 860px) {
  .nav-toggle { display: inline-block; }
  .menu { position: fixed; inset: 58px 0 auto 0; background: rgba(11,13,18,.96); border-bottom: 1px solid var(--border); display: grid; gap: .25rem; padding: .75rem 1rem 1rem; transform-origin: top; transform: scaleY(0); transition: transform .25s ease; }
  .menu li a { display: block; padding: .8rem; border-radius: .6rem; }
  .menu.is-open { transform: scaleY(1); }
}