/* ==========================================================================
   blue-andi.de – site styles (loaded after Bootstrap 5.3)
   ========================================================================== */

/* --- design tokens ------------------------------------------------------- */
:root,
[data-bs-theme="light"] {
  --ba-blue: #0b63ce;
  --ba-blue-rgb: 11, 99, 206;
  --ba-blue-dark: #084a9b;
  --ba-cyan: #16b3d1;
  --ba-green: #1fb954;
  --ba-hero-bg: linear-gradient(135deg, #f3f7fc 0%, #e4eefb 55%, #dcecf7 100%);
  --ba-hero-grid: rgba(11, 99, 206, 0.08);
  --ba-terminal-bg: #0d1b2a;
  --ba-terminal-fg: #5ef28a;
  --ba-terminal-muted: #7a8ca3;
  --ba-card-shadow: 0 0.5rem 1.5rem rgba(11, 36, 71, 0.08);
  --ba-card-shadow-hover: 0 1rem 2.5rem rgba(11, 36, 71, 0.16);

  --bs-primary: var(--ba-blue);
  --bs-primary-rgb: var(--ba-blue-rgb);
  --bs-link-color: var(--ba-blue);
  --bs-link-color-rgb: var(--ba-blue-rgb);
  --bs-link-hover-color: var(--ba-blue-dark);
  --bs-link-hover-color-rgb: 8, 74, 155;
  --bs-body-font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", "Noto Sans", "Liberation Sans", Arial, sans-serif;
  --bs-font-monospace: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
}

[data-bs-theme="dark"] {
  --ba-blue: #5aa9ff;
  --ba-blue-rgb: 90, 169, 255;
  --ba-blue-dark: #8cc3ff;
  --ba-hero-bg: linear-gradient(135deg, #0b1626 0%, #0e2240 55%, #0a1c33 100%);
  --ba-hero-grid: rgba(90, 169, 255, 0.10);
  --ba-terminal-bg: #06101c;
  --ba-card-shadow: 0 0.5rem 1.5rem rgba(0, 0, 0, 0.35);
  --ba-card-shadow-hover: 0 1rem 2.5rem rgba(0, 0, 0, 0.55);

  --bs-body-bg: #0f1722;
  --bs-body-bg-rgb: 15, 23, 34;
  --bs-tertiary-bg: #16212f;
  --bs-tertiary-bg-rgb: 22, 33, 47;
  --bs-secondary-bg: #1b2735;
  --bs-primary: var(--ba-blue);
  --bs-primary-rgb: var(--ba-blue-rgb);
  --bs-link-color: var(--ba-blue);
  --bs-link-color-rgb: var(--ba-blue-rgb);
  --bs-link-hover-color: var(--ba-blue-dark);
  --bs-link-hover-color-rgb: 140, 195, 255;
}

/* Bootstrap components read their own component-level variables. */
.btn-primary {
  --bs-btn-bg: var(--ba-blue);
  --bs-btn-border-color: var(--ba-blue);
  --bs-btn-hover-bg: var(--ba-blue-dark);
  --bs-btn-hover-border-color: var(--ba-blue-dark);
  --bs-btn-active-bg: var(--ba-blue-dark);
  --bs-btn-active-border-color: var(--ba-blue-dark);
  --bs-btn-disabled-bg: var(--ba-blue);
  --bs-btn-disabled-border-color: var(--ba-blue);
  --bs-btn-focus-shadow-rgb: var(--ba-blue-rgb);
}
[data-bs-theme="dark"] .btn-primary {
  --bs-btn-color: #06101c;
  --bs-btn-hover-color: #06101c;
  --bs-btn-active-color: #06101c;
}
.btn-outline-primary {
  --bs-btn-color: var(--ba-blue);
  --bs-btn-border-color: var(--ba-blue);
  --bs-btn-hover-bg: var(--ba-blue);
  --bs-btn-hover-border-color: var(--ba-blue);
  --bs-btn-active-bg: var(--ba-blue);
  --bs-btn-active-border-color: var(--ba-blue);
  --bs-btn-focus-shadow-rgb: var(--ba-blue-rgb);
}
[data-bs-theme="dark"] .btn-outline-primary {
  --bs-btn-hover-color: #06101c;
  --bs-btn-active-color: #06101c;
}
.text-primary { color: var(--ba-blue) !important; }
.bg-primary { background-color: var(--ba-blue) !important; }
.border-primary { border-color: var(--ba-blue) !important; }
.form-control:focus,
.form-select:focus {
  border-color: rgba(var(--ba-blue-rgb), 0.6);
  box-shadow: 0 0 0 0.25rem rgba(var(--ba-blue-rgb), 0.25);
}
.form-check-input:checked {
  background-color: var(--ba-blue);
  border-color: var(--ba-blue);
}

/* --- language switching (works without JavaScript: German is the default) */
html:not([lang="en"]) [data-lang="en"] { display: none !important; }
html[lang="en"] [data-lang="de"] { display: none !important; }

/* --- base ---------------------------------------------------------------- */
html { scroll-behavior: smooth; scroll-padding-top: 5rem; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
main { flex: 1 0 auto; }

h1, h2, h3, h4, .display-4, .display-5 {
  letter-spacing: -0.02em;
  font-weight: 700;
}
.section-title {
  position: relative;
  display: inline-block;
  padding-bottom: 0.5rem;
  margin-bottom: 1.5rem;
}
.section-title::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 3rem;
  height: 0.25rem;
  border-radius: 0.25rem;
  background: linear-gradient(90deg, var(--ba-blue), var(--ba-cyan));
}

/* skip link */
.skip-link {
  position: absolute;
  left: 1rem;
  top: -4rem;
  z-index: 2000;
  padding: 0.5rem 1rem;
  border-radius: 0.5rem;
  background: var(--ba-blue);
  color: #fff;
  transition: top 0.15s ease-in-out;
}
.skip-link:focus { top: 1rem; color: #fff; outline: 3px solid var(--ba-cyan); }

/* --- navbar -------------------------------------------------------------- */
.site-nav {
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  background-color: rgba(var(--bs-body-bg-rgb), 0.85);
  border-bottom: 1px solid var(--bs-border-color-translucent);
}
.site-nav .navbar-brand {
  font-weight: 700;
  letter-spacing: -0.01em;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}
.site-nav .navbar-brand img {
  width: 2rem;
  height: 2rem;
  border-radius: 50%;
}
.site-nav .nav-link {
  font-weight: 500;
  padding-left: 0.9rem;
  padding-right: 0.9rem;
  border-radius: 0.5rem;
}
.site-nav .nav-link.active {
  color: var(--ba-blue);
  background-color: rgba(var(--ba-blue-rgb), 0.1);
}
.site-nav .nav-link:focus-visible,
.site-nav .btn:focus-visible {
  outline: 3px solid rgba(var(--ba-blue-rgb), 0.5);
  outline-offset: 2px;
}
#lang-toggle .btn { min-width: 3rem; font-weight: 600; }
#lang-toggle .btn.active {
  background-color: var(--ba-blue);
  border-color: var(--ba-blue);
  color: #fff;
}
[data-bs-theme="dark"] #lang-toggle .btn.active { color: #06101c; }

/* --- hero ---------------------------------------------------------------- */
.hero {
  position: relative;
  overflow: hidden;
  background: var(--ba-hero-bg);
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--ba-hero-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--ba-hero-grid) 1px, transparent 1px);
  background-size: 2.5rem 2.5rem;
  mask-image: radial-gradient(ellipse at 70% 40%, #000 20%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at 70% 40%, #000 20%, transparent 75%);
  pointer-events: none;
}
.hero > .container { position: relative; }
.hero-avatar {
  width: min(70vw, 16rem);
  height: auto;
  border-radius: 50%;
  box-shadow: 0 0 0 0.5rem rgba(var(--ba-blue-rgb), 0.15), var(--ba-card-shadow-hover);
  image-rendering: auto;
}
.hero-tagline {
  font-size: 1.25rem;
  color: var(--bs-secondary-color);
}
.hero-badges .badge {
  font-weight: 500;
  padding: 0.5rem 0.75rem;
}

/* --- easter egg "terminal" ---------------------------------------------- */
.easter-egg {
  font-family: var(--bs-font-monospace);
  background: var(--ba-terminal-bg);
  color: var(--ba-terminal-fg);
  border-radius: 0.75rem;
  padding: 1rem 1.25rem;
  box-shadow: var(--ba-card-shadow);
  border: 1px solid rgba(94, 242, 138, 0.2);
  max-width: 34rem;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  font-size: 0.875rem;
}
.easter-egg .prompt { color: var(--ba-terminal-muted); user-select: none; }
.easter-egg .cursor {
  display: inline-block;
  width: 0.6em;
  height: 1.1em;
  margin-left: 0.15em;
  vertical-align: text-bottom;
  background: var(--ba-terminal-fg);
  animation: ba-blink 1.1s steps(1) infinite;
}
@keyframes ba-blink { 50% { opacity: 0; } }
.easter-egg .progress-bar-ascii { color: var(--ba-terminal-muted); letter-spacing: 0.05em; }

/* --- cards --------------------------------------------------------------- */
.card-lift {
  border: 1px solid var(--bs-border-color-translucent);
  box-shadow: var(--ba-card-shadow);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}
.card-lift:hover,
.card-lift:focus-within {
  transform: translateY(-0.2rem);
  box-shadow: var(--ba-card-shadow-hover);
}
.card-lift .card-title a { text-decoration: none; }
.card-lift .card-title a:hover { text-decoration: underline; }
.card-lift .card-title a::after {
  /* stretched link: the whole card is clickable */
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
}
.card-lift { position: relative; }
.card-lift .card-footer { background: transparent; border-top: 1px solid var(--bs-border-color-translucent); }
.card-lift .card-footer a,
.card-lift .card-footer button {
  position: relative;
  z-index: 2;
}

.language-dot {
  display: inline-block;
  width: 0.7rem;
  height: 0.7rem;
  border-radius: 50%;
  margin-right: 0.35rem;
  vertical-align: -0.05em;
  background: var(--bs-secondary-color);
}
.language-dot[data-language="C++"] { background: #f34b7d; }
.language-dot[data-language="C"] { background: #555555; }
.language-dot[data-language="Python"] { background: #3572a5; }
.language-dot[data-language="JavaScript"] { background: #f1e05a; }
.language-dot[data-language="TypeScript"] { background: #3178c6; }
.language-dot[data-language="HTML"] { background: #e34c26; }
.language-dot[data-language="Shell"] { background: #89e051; }
.language-dot[data-language="Rust"] { background: #dea584; }
.language-dot[data-language="Java"] { background: #b07219; }
.language-dot[data-language="Go"] { background: #00add8; }

.stat { display: inline-flex; align-items: center; gap: 0.3rem; white-space: nowrap; }

/* --- publications -------------------------------------------------------- */
.pub-cover {
  width: 100%;
  max-width: 11rem;
  height: auto;
  border-radius: 0.35rem;
  box-shadow: var(--ba-card-shadow);
}
.pub-cover-sm { max-width: 7rem; }
.pub-cover-placeholder {
  width: 9rem;
  height: 13rem;
  border-radius: 0.35rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  background: var(--bs-tertiary-bg);
  color: var(--bs-secondary-color);
}

/* --- legal pages --------------------------------------------------------- */
.legal-container { max-width: 50rem; }
.legal h2 { font-size: 1.35rem; margin-top: 2rem; }
.legal h3 { font-size: 1.1rem; margin-top: 1.25rem; }
.legal address { font-style: normal; }

/* --- footer -------------------------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--bs-border-color-translucent);
  background: var(--bs-tertiary-bg);
  font-size: 0.925rem;
}
.site-footer a { color: inherit; }
.site-footer a:hover { color: var(--ba-blue); }

/* --- misc ---------------------------------------------------------------- */
.icon-link { text-decoration: none; }
.icon-link:hover { text-decoration: underline; }
.text-mono { font-family: var(--bs-font-monospace); }