@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans:wght@400;500;600;700&family=IBM+Plex+Mono:wght@400;500&display=swap');

/* Same palette and type as the lecture slides */
:root{
 --bg:#FCFDFE;--surface:#FFFFFF;--fg:#0F141C;--muted:#586273;--accent:#1A5DB4;--accent-soft:#EDF4FB;--accent-border:rgba(26,93,180,.22);
 --line:rgba(20,20,20,.10);--line-strong:rgba(20,20,20,.16);--talk:#1E7F4F;--talk-soft:#E8F5EE;
 --font:'IBM Plex Sans',system-ui,-apple-system,'Segoe UI',sans-serif;--mono:'IBM Plex Mono',ui-monospace,Consolas,monospace;
 --radius:12px;--shadow:0 22px 50px -30px rgba(15,30,60,.5);
}
@media (prefers-color-scheme:dark){:root{
 --bg:#0C1117;--surface:#131A23;--fg:#E6EBF2;--muted:#94A0B2;--accent:#6EA8F0;--accent-soft:rgba(110,168,240,.12);--accent-border:rgba(110,168,240,.3);
 --line:rgba(255,255,255,.09);--line-strong:rgba(255,255,255,.16);--talk:#5CC48F;--talk-soft:rgba(92,196,143,.12);--shadow:0 22px 50px -30px rgba(0,0,0,.8);
}}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--fg);font-family:var(--font);font-size:16px;line-height:1.58;-webkit-font-smoothing:antialiased;min-height:100vh;display:flex;flex-direction:column}
a{color:var(--accent)}
button,select,input{font:inherit;color:inherit}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.wrap{width:100%;max-width:960px;margin:0 auto;padding:0 24px}

/* language: both texts are in the page, the html lang attribute picks one */
html[lang=de] [data-l=en],html[lang=en] [data-l=de]{display:none}

/* header */
.site-header .wrap{position:relative}
.language-control{position:absolute;top:-40px;right:24px}
.language-control select{height:auto;background:var(--surface);border:1px solid var(--line-strong);border-radius:8px;padding:4px 22px 4px 8px;font-size:12.5px;font-weight:600;letter-spacing:.04em;cursor:pointer}
.site-header{background:linear-gradient(180deg,var(--accent-soft),transparent);border-bottom:1px solid var(--line);padding:64px 0 40px}
h1{margin:0 0 14px;font-size:clamp(30px,5vw,44px);line-height:1.12;letter-spacing:-.015em;font-weight:700}
.intro{margin:0;max-width:62ch;color:var(--muted);font-size:17px}

/* toolbar */
main.wrap{flex:1;padding-top:32px;padding-bottom:56px}
.toolbar{display:flex;flex-wrap:wrap;gap:12px;align-items:center;justify-content:space-between;margin-bottom:22px}
.segmented{display:inline-flex;background:var(--surface);border:1px solid var(--line-strong);border-radius:10px;padding:3px;gap:2px}
.segmented button{border:0;background:none;border-radius:7px;padding:6px 12px;font-size:14px;font-weight:500;cursor:pointer;color:var(--muted)}
.segmented button .count{font-family:var(--mono);font-size:12px;margin-left:4px;opacity:.75}
.segmented button:hover{color:var(--fg)}
.segmented button[aria-pressed=true]{background:var(--accent);color:#fff}
@media (prefers-color-scheme:dark){.segmented button[aria-pressed=true]{color:#0C1117}}
.toolbar-right{display:flex;gap:8px;flex-wrap:wrap}
select,input[type=search]{background:var(--surface);border:1px solid var(--line-strong);border-radius:10px;padding:6px 10px;font-size:14px;height:38px}
input[type=search]{width:220px;max-width:100%}

/* cards */
.cards{list-style:none;margin:0;padding:0;display:grid;gap:14px}
.card[hidden]{display:none}
.card-link{display:grid;grid-template-columns:96px 1fr auto;gap:22px;align-items:start;padding:22px 24px;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);color:inherit;text-decoration:none;transition:border-color .15s,box-shadow .15s,transform .15s}
.card-link:hover{border-color:var(--accent-border);box-shadow:var(--shadow);transform:translateY(-1px)}
.card-date{display:flex;flex-direction:column;align-items:flex-start;padding-top:2px;border-right:1px solid var(--line);padding-right:16px;min-height:100%}
.card-month{font-size:13px;color:var(--muted)}
.card-year{font-family:var(--mono);font-size:24px;font-weight:500;line-height:1.2;color:var(--accent)}
.card-meta{display:flex;gap:6px;align-items:center;margin-bottom:8px;flex-wrap:wrap}
.badge{font-size:12px;font-weight:600;padding:2px 8px;border-radius:999px;background:var(--accent-soft);color:var(--accent)}
.badge-talk{background:var(--talk-soft);color:var(--talk)}
.lang{font-family:var(--mono);font-size:11px;padding:1px 6px;border:1px solid var(--line-strong);border-radius:5px;color:var(--muted)}
.card h2{margin:0;font-size:21px;line-height:1.25;font-weight:600;letter-spacing:-.005em}
.card-subtitle{margin:4px 0 0;font-weight:500}
.card-venue{margin:2px 0 0;color:var(--muted);font-size:15px}
.card-summary{margin:12px 0 0;color:var(--muted);font-size:15px;max-width:64ch}
.tags{list-style:none;margin:14px 0 0;padding:0;display:flex;flex-wrap:wrap;gap:6px}
.tags li{font-size:12.5px;padding:2px 9px;border-radius:6px;background:var(--bg);border:1px solid var(--line);color:var(--muted)}
.card-open{align-self:center;display:inline-flex;align-items:center;gap:6px;font-size:14px;font-weight:600;color:var(--accent);white-space:nowrap}
.card-open svg{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;transition:transform .15s}
.card-link:hover .card-open svg{transform:translateX(3px)}
.empty{color:var(--muted);text-align:center;padding:40px 0}

.site-footer{border-top:1px solid var(--line);padding:20px 0;font-size:13px;color:var(--muted)}

@media (max-width:680px){
 .wrap{padding:0 16px}
 .language-control{top:-28px;right:16px}
 .site-header{padding:40px 0 28px}
 .card-link{grid-template-columns:1fr;gap:12px;padding:18px}
 .card-date{flex-direction:row;gap:8px;align-items:baseline;border-right:0;padding-right:0}
 .card-year{font-size:18px}
 .card-open{justify-self:start}
 .toolbar-right,input[type=search]{flex:1}
 .toolbar-right select{flex:none}
}