/* Semantic Field · Visual tokens · v0.3.10 */
@font-face {
  font-family: "IBM Plex Sans";
  src: url("/assets/fonts/IBMPlexSans-Regular.woff2") format("woff2");
  font-style: normal;
  font-weight: 400;
  font-display: swap;
}
@font-face {
  font-family: "IBM Plex Sans";
  src: url("/assets/fonts/IBMPlexSans-SemiBold.woff2") format("woff2");
  font-style: normal;
  font-weight: 600;
  font-display: swap;
}
@font-face {
  font-family: "IBM Plex Sans";
  src: url("/assets/fonts/IBMPlexSans-Bold.woff2") format("woff2");
  font-style: normal;
  font-weight: 700;
  font-display: swap;
}
@font-face {
  font-family: "IBM Plex Mono";
  src: url("/assets/fonts/IBMPlexMono-Regular.woff2") format("woff2");
  font-style: normal;
  font-weight: 400;
  font-display: swap;
}
@font-face {
  font-family: "IBM Plex Mono";
  src: url("/assets/fonts/IBMPlexMono-SemiBold.woff2") format("woff2");
  font-style: normal;
  font-weight: 600;
  font-display: swap;
}
@font-face {
  font-family: "IBM Plex Mono";
  src: url("/assets/fonts/IBMPlexMono-Bold.woff2") format("woff2");
  font-style: normal;
  font-weight: 700;
  font-display: swap;
}

:root {
  color-scheme: light;

  /* Neutral palette */
  --sf-gray-0: #ffffff;
  --sf-gray-25: #f8fafc;
  --sf-gray-50: #f5f7fa;
  --sf-gray-100: #eef2f7;
  --sf-gray-200: #dce2ea;
  --sf-gray-300: #bcc6d4;
  --sf-gray-500: #667085;
  --sf-gray-600: #475467;
  --sf-gray-700: #364153;
  --sf-gray-900: #172033;

  /* Brand and interaction */
  --sf-brand: #3559c7;
  --sf-brand-hover: #27459f;
  --sf-brand-soft: #e9edfb;

  /* Content status tags */
  --sf-status-tag-text: #64748b;
  --sf-status-tag-bg: #f1f5f9;

  /* Standard UI feedback */
  --sf-info: #3559c7;
  --sf-info-soft: #e9edfb;
  --sf-success: #26735f;
  --sf-success-soft: #e4f1ed;
  --sf-warning: #a86519;
  --sf-warning-soft: #f8eddd;
  --sf-danger: #b54747;
  --sf-danger-soft: #f8e8e8;

  /* Surface aliases */
  --sf-page: var(--sf-gray-50);
  --sf-surface: var(--sf-gray-0);
  --sf-surface-subtle: var(--sf-gray-100);
  --sf-text: var(--sf-gray-900);
  --sf-text-secondary: var(--sf-gray-700);
  --sf-text-muted: var(--sf-gray-500);
  --sf-border: var(--sf-gray-200);
  --sf-border-strong: var(--sf-gray-300);

  /* Font families */
  --sf-font-sans: "IBM Plex Sans", "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --sf-font-mono: "IBM Plex Mono", "SFMono-Regular", Consolas, monospace;

  /* Type scale */
  --sf-heading-1: 3.5rem;   /* 56px */
  --sf-heading-2: 2.5rem;   /* 40px */
  --sf-heading-3: 2rem;     /* 32px */
  --sf-heading-4: 1.5rem;   /* 24px */
  --sf-heading-5: 1.25rem;  /* 20px */
  --sf-heading-6: 1rem;     /* 16px */
  --sf-body-lg: 1.125rem;   /* 18px */
  --sf-body-md: 1rem;       /* 16px */
  --sf-body-sm: 0.875rem;   /* 14px */
  --sf-caption: 0.75rem;    /* 12px — minimum */

  --sf-leading-display: 1.1;
  --sf-leading-heading: 1.25;
  --sf-leading-body: 1.7;
  --sf-leading-compact: 1.45;
  --sf-tracking-display: -0.025em;
  --sf-tracking-label: 0.06em;

  /* Four-pixel spacing scale */
  --sf-space-1: 0.25rem;
  --sf-space-2: 0.5rem;
  --sf-space-3: 0.75rem;
  --sf-space-4: 1rem;
  --sf-space-5: 1.25rem;
  --sf-space-6: 1.5rem;
  --sf-space-8: 2rem;
  --sf-space-10: 2.5rem;
  --sf-space-12: 3rem;
  --sf-space-16: 4rem;
  --sf-space-20: 5rem;
  --sf-space-24: 6rem;

  /* Layout */
  --sf-page-max: 80rem;
  --sf-content-max: 72rem;
  --sf-reading-max: 45rem;
  --sf-gutter: clamp(1.25rem, 4vw, 4rem);
  --sf-header-height: 4rem;
  --sf-sidebar-width: 16rem;
  --sf-nav-item-height: 2.75rem;

  /* Shape and depth */
  --sf-radius-sm: 0.25rem;
  --sf-radius-md: 0.5rem;
  --sf-radius-lg: 0.75rem;
  --sf-radius-pill: 999px;
  --sf-shadow-sm: 0 1px 3px rgb(23 32 51 / 0.1);
  --sf-shadow-overlay: 0 18px 48px rgb(23 32 51 / 0.16);

  /* Motion */
  --sf-duration-fast: 120ms;
  --sf-duration-base: 220ms;
  --sf-ease-out: cubic-bezier(0.16, 1, 0.3, 1);
}

* { box-sizing: border-box; }
html { font-family: var(--sf-font-sans); font-size: 16px; color: var(--sf-text); background: var(--sf-page); scroll-behavior: smooth; }
body { margin: 0; min-width: 20rem; font-size: var(--sf-body-md); line-height: var(--sf-leading-body); -webkit-font-smoothing: antialiased; }
button, input, textarea, select { font: inherit; }
a { color: inherit; }
:focus-visible { outline: 2px solid var(--sf-brand); outline-offset: 3px; }
::selection { color: var(--sf-text); background: var(--sf-brand-soft); }

/* Responsive tiers: navigation 68rem · layout 52rem · compact 38rem */
@media (max-width: 52rem) {
  :root { --sf-heading-1: 2.5rem; --sf-heading-2: 2rem; --sf-heading-3: 1.75rem; --sf-gutter: 1.25rem; }
}

@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; }
}