/* User-controlled light / dark / system preference, independent from reader permissions. */
.site-header nav{margin-left:auto}
.reader-theme-picker{position:relative;flex-shrink:0;margin-left:8px;font-family:var(--font-ui)}
.reader-theme-picker>summary{list-style:none;width:40px;height:44px;display:grid;place-items:center;cursor:pointer;border:1px solid transparent;border-radius:2px;color:var(--ink-soft)}
.reader-theme-picker>summary::-webkit-details-marker{display:none}
.reader-theme-picker>summary:hover,.reader-theme-picker[open]>summary{background:var(--paper-deep);color:var(--ink);border-color:var(--rule)}
.reader-theme-picker>summary .reading-icon{width:20px;height:20px}
.theme-choices{position:absolute;right:0;top:calc(100% + 9px);z-index:60;width:174px;padding:7px;background:var(--paper);border:1px solid var(--rule-strong);box-shadow:0 12px 30px #00000018}
.theme-choices button{width:100%;min-height:44px;display:flex;align-items:center;gap:12px;border:0;background:none;color:var(--ink-soft);font:12px var(--font-ui);padding:10px 12px;text-align:left;cursor:pointer}
.theme-choices button .reading-icon{width:18px;height:18px}
.theme-choices button[aria-pressed="true"]{color:var(--ink);background:var(--paper-deep)}
.theme-choices button[aria-pressed="true"]::after{content:'✓';margin-left:auto;color:var(--teal)}
.theme-choices button:hover{color:var(--teal)}
@media(max-width:520px){.site-header__inner{gap:8px}.reader-theme-picker{margin-left:0}.site-header nav{gap:12px}.site-header nav a[href="./index.html"],.site-header nav a[href="../index.html"]{display:none}.reader-theme-picker>summary{width:38px}.site-header__brand{font-size:21px}}
@media(max-width:360px){.site-header__inner{padding-inline:18px}.site-header nav{gap:8px}.site-header__brand{font-size:20px}.site-header__logo{width:21px;height:21px}.reader-theme-picker>summary{width:34px}}
@media(forced-colors:active){.theme-choices{background:Canvas;color:CanvasText;border-color:CanvasText}.theme-choices button[aria-pressed="true"]{outline:1px solid Highlight}}
@media print{.reader-theme-picker{display:none!important}:root{color-scheme:light;--paper:#fff;--ink:#000}}