/* CSS Custom Properties for SNSF Leading House Asia Site */
/* Created: December 2024 */

:root {
  /* Primary Colors */
  --color-primary: #1e3a5f;
  --color-accent: #2563eb;

  /* Background Colors */
  --color-bg-page: #f8fafc;
  --color-bg-white: #ffffff;
  --color-bg-light: #f1f5f9;
  --color-bg-alt: #f6f8fa;

  /* Border Colors */
  --color-border: #e1e4e8;
  --color-border-light: #e2e8f0;
  --color-border-lighter: #f0f0f0;

  /* Text Colors */
  --color-text-primary: #1e293b;
  --color-text-secondary: #475569;
  --color-text-muted: #64748b;
  --color-text-light: #94a3b8;
  --color-text-nav: #586069;
  --color-text-heading: #24292e;

  /* Link Colors */
  --color-link: #2563eb;
  --color-link-hover: #1d4ed8;
  --color-link-footer: #93c5fd;

  /* Special Colors */
  --color-news-bg: #fef3c7;
  --color-news-text: #92400e;
  --color-badge-bg: #e0e7ff;
  --color-badge-text: #3730a3;
  --color-orcid: #a3e635;
  --color-success: #22c55e;
  --color-warning: #f59e0b;

  /* Gradients */
  --gradient-primary: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
  --gradient-hero: linear-gradient(135deg, #1e3a5f 0%, #2563eb 100%);

  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --font-family-mono: SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace;

  /* Font Sizes - Minimum 0.85rem (11px) for accessibility */
  --font-size-xs: 0.85rem;      /* 13.6px - minimum readable */
  --font-size-sm: 0.875rem;     /* 14px */
  --font-size-base: 1rem;       /* 16px */
  --font-size-lg: 1.125rem;     /* 18px */
  --font-size-xl: 1.25rem;      /* 20px */
  --font-size-2xl: 1.5rem;      /* 24px */

  /* Line Heights */
  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;

  /* Spacing */
  --spacing-xs: 2px;
  --spacing-sm: 4px;
  --spacing-md: 8px;
  --spacing-lg: 12px;
  --spacing-xl: 16px;
  --spacing-2xl: 24px;
  --spacing-3xl: 32px;

  /* Border Radius */
  --radius-sm: 2px;
  --radius-md: 4px;
  --radius-lg: 6px;
  --radius-xl: 8px;
  --radius-full: 50%;

  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 200ms ease;
  --transition-slow: 300ms ease;

  /* Layout */
  --sidebar-width: 180px;
  --nav-height: 36px;
  --content-max-width: 900px;

  /* Navigation */
  --nav-bg: #1e3a5f;
  --nav-font-size: 0.85rem;
  --nav-padding: 6px 12px;
  --nav-gap: 12px;
  --nav-link-opacity: 0.9;
  --nav-link-opacity-hover: 1;

  /* Mobile Breakpoint */
  --breakpoint-mobile: 768px;
}

/* Accessibility: Visually hidden but accessible to screen readers */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Focus states for keyboard navigation */
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible,
details summary:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* Remove outline for mouse users */
:focus:not(:focus-visible) {
  outline: none;
}