:root {
  --paper:      #F2F4EC;
  --surface:    #FBFCF8;
  --surface-rgb: 251, 252, 248;
  --ink:        #1C231D;
  --muted:      #545F4B;
  --add:        #1E7A46;
  --remove:     #B23A2E;
  --border:     #D9DFCF;

  /* font stack prefers easy-to-read (UD) system fonts */
  /* cf. https://share.google/aimode/o3jKsNakJxBCvWzSh */
  /* it is better to put language is outside and devices spec is inside */
  /* it is because of maintenance efficiency */
  --font-sans:
    /* [English Fonts] */
    /* Apple devices */
    -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial,
    /* Windows */
    
    /* Android */
    "Roboto", "Droid Sans",
    /* Linux */
    "Ubuntu", "Liberation Sans", "DejaVu Sans",
    /* [Japanese Fonts] */
    /* Apple devices */
    "Hiragino Sans", "Hiragino Kaku Gothic Neo", "Hiragino Kaku Gothic ProN",
    /* Windows */
    "BIZ UDPGothic", "Noto Sans Jp", "Meiryo", "メイリオ",
    /* Android */
    "Noto Sans CJK JP",
    /* Linux */
    "Noto Sans",
    /* last resort */
    sans-serif;
  
  --font-mono:
    /* [English Fonts] */
    /* Apple devices */
    "SF Mono", "Menlo", "Monaco",
    /* Windows */
    "Cascadia Code", "Consolas", "Courier New",
    /* Android */
    "Roboto Mono", "Droid Sans Mono",
    /* Linux */
    "Ubuntu Mono", "Liberation Mono", "DejaVu Sans Mono",
    /* [Japanese Fonts] */
    /* Apple devices */
    
    /* Windows */
    "BIZ UDGothic",
    /* Android */
    "Noto Sans Mono",
    /* Linux */

    /* last resort */
    monospace;
  
  /* old font stack */
  /*
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --font-sans: 'Noto Sans JP', 'Hiragino Sans', system-ui, -apple-system, sans-serif;
  */
  --space-1: 0.5rem;
  --space-2: 1rem;
  --space-3: 1.75rem;
  --space-4: 3rem;
  --space-5: 5rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper:      #14170F;
    --surface:    #1B1F17;
    --surface-rgb: 27, 31, 23;
    --ink:        #E8ECDF;
    --muted:      #ADB89F;
    --add:        #4CC98A;
    --remove:     #E2695C;
    --border:     #2C3226;
  }
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  min-height: 100%;
}

body {
  background-color: var(--paper);
  background-image: var(--bg-image, none);
  background-position: center bottom;
  background-size: cover;
  background-repeat: no-repeat;
  background-attachment: fixed;
  color: var(--ink);
  font-family: var(--font-sans);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--add); text-decoration: none; }
a:hover { text-decoration: underline; }
a:focus-visible, button:focus-visible {
  outline: 2px solid var(--add);
  outline-offset: 3px;
}

.terminal {
  max-width: 640px;
  margin: 0 auto;
  padding: var(--space-5) var(--space-3) var(--space-4);
  background-color: rgba(var(--surface-rgb), 0.8);
}

.prompt {
  font-family: var(--font-mono);
  color: var(--muted);
  font-size: 0.875rem;
  margin: 0 0 var(--space-2);
}
.prompt-sym { color: var(--add); margin-right: 0.4em; }

.diff-head {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--muted);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: var(--space-1) var(--space-2);
  margin: 0 0 var(--space-2);
  line-height: 1.6;
}

.hero { margin-bottom: var(--space-4); }

.name {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(2rem, 7vw, 3.25rem);
  margin: 0;
  letter-spacing: -0.01em;
}
.name::after {
  content: '';
  display: inline-block;
  width: 0.5em;
  height: 0.85em;
  background: var(--add);
  margin-left: 0.15em;
  vertical-align: -0.08em;
  animation: blink 1.1s steps(1) infinite;
}
@media (prefers-reduced-motion: reduce) {
  .name::after { animation: none; opacity: 0.6; }
}
@keyframes blink { 0%, 49% { opacity: 1; } 50%, 100% { opacity: 0; } }

.role {
  font-family: var(--font-mono);
  color: var(--add);
  font-size: 1rem;
  margin: var(--space-1) 0 0;
}

.section-title,
.prose h2 {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  color: var(--muted);
  margin: 0 0 var(--space-2);
  font-weight: 600;
}
.section-title::before,
.prose h2::before { content: '## '; color: var(--border); }

.about { margin-bottom: var(--space-4); }
.prose p { margin: 0 0 var(--space-2); }

.links { margin-bottom: var(--space-4); }
.link-group + .link-group { margin-top: var(--space-3); }
.link-group summary.prompt {
  cursor: pointer;
  list-style: none;
  user-select: none;
  display: flex;
  align-items: center;
}
.link-group summary.prompt::-webkit-details-marker { display: none; }
.link-group summary.prompt::after {
  content: '▸';
  margin-left: auto;
  color: var(--muted);
  transition: transform 0.15s ease;
}
.link-group[open] summary.prompt::after { transform: rotate(90deg); }
.link-group summary.prompt:hover,
.link-group summary.prompt:focus-visible {
  color: var(--add);
}
.link-group summary.prompt:focus-visible { outline: 2px solid var(--add); outline-offset: 3px; }
.ls-list { list-style: none; margin: 0; padding: 0; }
.ls-list li + li { margin-top: var(--space-1); }
.ls-list a {
  display: flex;
  gap: var(--space-1);
  align-items: baseline;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--ink);
  padding: var(--space-1);
  border-radius: 4px;
  flex-wrap: wrap;
}
.ls-list a:hover, .ls-list a:focus-visible {
  background: var(--surface);
  text-decoration: none;
}
.ls-list .perm { color: var(--border); }
.ls-list .licon { display: inline-flex; color: var(--muted); }
.ls-list .licon svg { width: 1em; height: 1em; fill: currentColor; }
.ls-list .lname { color: var(--add); font-weight: 600; }
.ls-list .arrow { color: var(--muted); }
.ls-list .lurl { color: var(--muted); word-break: break-all; }

.lang-switch { margin-bottom: var(--space-2); }
.lang-switch ul {
  list-style: none;
  display: flex;
  gap: var(--space-2);
  padding: 0;
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  flex-wrap: wrap;
}
.lang-switch a { color: var(--muted); }
.lang-switch a.current {
  color: var(--ink);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-color: var(--add);
  text-decoration-thickness: 2px;
}

@media (max-width: 480px) {
  .terminal { padding: var(--space-4) var(--space-2) var(--space-3); }
}