:root {
  /* Light theme (default) */
  color-scheme: light;
  --bg: #ffffff;
  --surface: #f8fafc;
  --surface-strong: #f1f5f9;
  --surface-soft: rgba(0,0,0,0.04);
  --text: #0b1220;
  --muted: #475569;
  --accent: #2563eb;
  --accent-foreground: #ffffff;
  --accent-soft: rgba(37,99,235,0.12);
  --border: rgba(0,0,0,0.08);
  --shadow: rgba(15, 23, 42, 0.12);
  --overlay: rgba(15, 23, 42, 0.42);
}

[data-theme="dark"] {
  color-scheme: dark;
  --bg: #070b16;
  --surface: #0f172a;
  --surface-strong: #111b2d;
  --surface-soft: rgba(255,255,255,0.06);
  --text: #e8eef9;
  --muted: #94a3b8;
  --accent: #60a5fa;
  --accent-foreground: #ffffff;
  --accent-soft: rgba(96,165,250,0.14);
  --border: rgba(255,255,255,0.1);
  --shadow: rgba(0, 0, 0, 0.35);
  --overlay: rgba(0, 0, 0, 0.66);
}

* { box-sizing: border-box; }
html,body{margin:0;min-height:100%;font-family:'Inter',system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;color:var(--text);}
[data-theme="light"] html,[data-theme="light"] body{background:#f5f8fc;}
[data-theme="light"] body::before{content:"";position:fixed;inset:0;z-index:-2;pointer-events:none;background:radial-gradient(circle at 18% 6%, rgba(37,99,235,0.1), transparent 36%), radial-gradient(circle at 84% 94%, rgba(37,99,235,0.06), transparent 30%), linear-gradient(180deg, #f8fafc 0%, #eef2f8 52%, #f8fafc 100%);}
[data-theme="light"] body::after{content:"";position:fixed;inset:0;z-index:-1;pointer-events:none;background-image:radial-gradient(circle, rgba(37,99,235,0.16) 1px, transparent 1px), linear-gradient(rgba(37,99,235,0.055) 1px, transparent 1px), linear-gradient(90deg, rgba(37,99,235,0.055) 1px, transparent 1px);background-size:24px 24px, 48px 48px, 48px 48px;mask-image:radial-gradient(ellipse at center, #000 42%, transparent 100%);}
[data-theme="dark"] html,[data-theme="dark"] body{background:#070b16;}
[data-theme="dark"] body::before{content:"";position:fixed;inset:0;z-index:-2;pointer-events:none;background:radial-gradient(circle at 18% 8%, rgba(96,165,250,0.12), transparent 34%), radial-gradient(circle at 82% 92%, rgba(37,99,235,0.08), transparent 28%), linear-gradient(180deg, #070b16 0%, #0a1020 55%, #070b16 100%);}
[data-theme="dark"] body::after{content:none;}
.matrix-bg{position:fixed;inset:0;z-index:-1;pointer-events:none;opacity:0.72;}
body{display:flex;align-items:center;justify-content:center;padding:32px;position:relative}
.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}

.page{width:min(100%,520px);padding:30px;border-radius:24px;background:linear-gradient(180deg,rgba(255,255,255,0.88),rgba(255,255,255,0.76));border:1px solid var(--border);box-shadow:0 30px 80px var(--shadow);position:relative;backdrop-filter:blur(10px)}
[data-theme="dark"] .page{background:linear-gradient(180deg,rgba(15,23,42,0.92),rgba(15,23,42,0.72));backdrop-filter:blur(12px)}

/* Theme toggle */
.theme-toggle{position:absolute;top:12px;right:12px;z-index:1400;background:transparent;border:1px solid var(--border);color:var(--text);padding:8px;border-radius:8px;cursor:pointer;font-size:18px;display:inline-flex;align-items:center;justify-content:center;width:40px;height:40px}
.theme-toggle:hover{transform:translateY(-2px)}

/* Modal pop animation */
.modal-overlay{transition:opacity .18s ease;opacity:0}
.modal-overlay.open{opacity:1}
.modal-overlay .modal-dialog{transform:scale(.88);opacity:0;transition:transform .22s cubic-bezier(.2,.9,.3,1),opacity .22s ease}
.modal-overlay.open .modal-dialog{transform:scale(1);opacity:1}


/* Hero */
.hero{display:grid;grid-template-columns:124px 1fr;gap:22px;align-items:center}
.avatar-wrap{width:124px;height:124px;border-radius:22px;overflow:hidden;border:1px solid var(--border);box-shadow:0 18px 40px rgba(15,23,42,0.16), inset 0 0 0 1px rgba(0,0,0,0.02)}
.avatar-wrap img{width:100%;height:100%;object-fit:cover;display:block}
.title-group{display:grid;gap:8px}
h1{margin:0;font-size:clamp(2rem,4vw,2.45rem);line-height:1.08}

p.role{margin:0;color:var(--accent);font-weight:600}
.intro{margin:0;color:var(--muted);font-size:0.98rem;line-height:1.55}

.highlights{display:flex;flex-wrap:wrap;gap:8px;margin-top:22px}
.highlights span{display:inline-flex;align-items:center;min-height:30px;padding:6px 10px;border-radius:999px;background:var(--surface);border:1px solid var(--border);color:var(--muted);font-size:0.8rem;font-weight:700}
.highlights .highlight-java{background:var(--accent-soft);color:var(--accent);border-color:color-mix(in srgb,var(--accent) 28%,var(--border))}
.highlights .highlight-security{background:rgba(245,158,11,0.14);color:#fbbf24;border-color:color-mix(in srgb,#f59e0b 32%,var(--border));box-shadow:0 0 0 1px rgba(251,191,36,0.1) inset}
[data-theme="light"] .highlights .highlight-security{background:rgba(217,119,6,0.1);color:#d97706;border-color:color-mix(in srgb,#d97706 28%,var(--border));box-shadow:none}

.links{margin:26px 0 0;display:flex;flex-wrap:wrap;justify-content:center;gap:12px;align-items:stretch}
.link-card:not(.primary-cta){flex:0 0 calc((100% - 36px) / 4);max-width:calc((100% - 36px) / 4)}
.link-card{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:14px 12px;height:92px;border-radius:12px;background:var(--surface);border:1px solid var(--border);text-decoration:none;color:inherit;transition:transform .15s ease, border-color .15s ease, background .15s ease}
button.link-card{font:inherit;cursor:pointer}
.link-card:hover{transform:translateY(-2px);background:var(--surface-strong);border-color:var(--accent-soft)}
.link-card .label svg{width:34px;height:34px;flex-shrink:0}
.link-card .label .qr-icon{width:36px;height:36px}
.link-card .label .label-text{display:block;font-size:0.95rem;color:var(--muted)}
.link-card:not(.primary-cta) .label .label-text{display:none}
button.link-card .label .label-text{display:none}
button.link-card.has-feedback .label .label-text{display:block}

/* Primary CTA - improved contrast across themes */
.link-card.primary-cta{
  background: linear-gradient(180deg, var(--accent), color-mix(in srgb, var(--accent) 85%, black 15%));
  color: var(--accent-foreground);
  border: 1px solid color-mix(in srgb, var(--accent) 40%, black 60%);
  padding: 18px 20px;
  font-weight: 700;
  box-shadow: 0 10px 30px rgba(0,0,0,0.12);
  flex: 1 1 100%;
  width: 100%;
  border-radius: 18px;
  text-shadow: 0 1px 0 rgba(0,0,0,0.15);
}
/* ensure SVG and label are visible and inline */
.link-card.primary-cta .label{display:flex;flex-direction:row;align-items:center;gap:12px}
.link-card.primary-cta .label svg{filter:brightness(0) invert(1);width:20px;height:20px}
.link-card.primary-cta .label .label-text{display:block;color:var(--accent-foreground);font-size:1rem}

/* Light-theme tweak: stronger border and subtle lift */
:root .link-card.primary-cta{border-color: color-mix(in srgb, var(--accent) 45%, black 55%);}

[data-theme="light"] .link-card.primary-cta{
  box-shadow: 0 6px 18px rgba(37,99,235,0.16);
  border-color: color-mix(in srgb, var(--accent) 45%, white 20%);
}

[data-theme="dark"] .link-card.primary-cta{
  box-shadow: 0 8px 26px rgba(0,0,0,0.45);
}

.link-card.primary-cta:focus,
.link-card.primary-cta:focus-visible{
  outline: 3px solid color-mix(in srgb, var(--accent) 60%, white 40%);
  outline-offset: 3px;
}

.link-card.primary-cta:hover{transform:translateY(-3px)}

.content-section{margin-top:28px;padding-top:24px;border-top:1px solid var(--border)}
.section-heading{display:grid;gap:4px;margin-bottom:14px}
.section-heading h2{margin:0;font-size:1.28rem;line-height:1.2}
.presentation-list{display:grid;gap:12px}
.presentation-card{display:grid;grid-template-columns:132px 1fr;gap:16px;align-items:stretch;padding:12px;border-radius:18px;background:var(--surface);border:1px solid var(--border)}
.presentation-card img{width:100%;height:100%;min-height:148px;object-fit:cover;border-radius:12px;border:1px solid var(--border)}
.presentation-content{display:grid;align-content:center;gap:8px}
.presentation-content h3{margin:0;font-size:1.05rem;line-height:1.25}
.presentation-content p{margin:0;font-size:0.92rem;line-height:1.55}
.item-kicker{color:var(--accent);font-weight:800;text-transform:uppercase;letter-spacing:0.12em;font-size:0.72rem!important}
.action-row{display:flex;flex-wrap:wrap;gap:8px;margin-top:4px}
.action-button{display:inline-flex;align-items:center;justify-content:center;min-height:38px;padding:10px 14px;border-radius:10px;background:var(--accent);color:var(--accent-foreground);text-decoration:none;font-weight:700;font-size:0.88rem}
.action-button.secondary{background:var(--surface-soft);color:var(--text);border:1px solid var(--border)}
.action-button:hover{transform:translateY(-1px)}
.qa-list{display:grid;gap:10px}
.qa-item{border:1px solid var(--border);border-radius:14px;background:var(--surface);overflow:hidden}
.qa-item summary{cursor:pointer;list-style:none;padding:14px 16px;font-weight:700;line-height:1.35}
.qa-item summary::-webkit-details-marker{display:none}
.qa-item summary::after{content:"+";float:right;color:var(--accent);font-weight:800}
.qa-item[open] summary::after{content:"-"}
.qa-item p{margin:0;padding:0 16px 16px;font-size:0.92rem}
.section-cta{margin-top:14px}

/* Shared page content */
p{color:var(--muted);line-height:1.7}
.subtitle{margin:0;color:var(--muted);line-height:1.7}
.footer{margin-top:18px;font-size:0.95rem;color:var(--muted)}

/* QR and modal */
.qr-box{display:grid;place-items:center;gap:18px;padding:16px;border-radius:28px;background:var(--surface);border:1px solid var(--border)}
.qr-box img{width:min(100%,320px);height:auto;border-radius:24px;background:#0d1525}
.cta-button{display:inline-flex;align-items:center;justify-content:center;width:100%;padding:14px 16px;border-radius:16px;background:var(--accent);color:var(--accent-foreground);text-decoration:none;font-weight:600;transition:transform .15s ease,opacity .15s ease}
.cta-button:hover{transform:translateY(-2px);opacity:0.95}

.modal-overlay{position:fixed;inset:0;display:none;align-items:center;justify-content:center;padding:22px;background:var(--overlay);z-index:1200;backdrop-filter:blur(8px)}
.modal-overlay.open{display:flex}
.modal-dialog{position:relative;background:transparent;padding:18px;border-radius:12px}
.qr-dialog{padding:22px}
.modal-dialog img{width:min(80vw,420px);height:auto;border-radius:8px;background:white;padding:8px}
.modal-close{position:absolute;top:6px;right:6px;width:36px;height:36px;border-radius:999px;border:1px solid var(--border);background:var(--surface);color:var(--text);font-size:24px;line-height:1;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;box-shadow:0 12px 28px var(--shadow)}
.modal-close:hover{transform:translateY(-1px);background:var(--surface-strong)}
.modal-panel{width:min(100%,520px);max-height:min(720px,86vh);overflow:auto;padding:26px;border-radius:24px;background:var(--surface);border:1px solid var(--border);box-shadow:0 34px 90px var(--shadow)}
.modal-heading{padding-right:38px}
.modal-heading h2{margin:4px 0 0;font-size:1.55rem;line-height:1.2}
.eyebrow{margin:0;color:var(--accent);font-size:0.78rem;font-weight:700;text-transform:uppercase;letter-spacing:0.14em}
.article-list{display:grid;gap:10px;margin-top:20px}
.article-link{display:flex;align-items:center;justify-content:space-between;gap:16px;min-height:56px;padding:14px 16px;border-radius:14px;background:var(--surface-soft);border:1px solid var(--border);color:var(--text);text-decoration:none;line-height:1.35;transition:transform .15s ease,background .15s ease,border-color .15s ease}
.article-link:hover{transform:translateY(-2px);background:var(--surface-strong);border-color:var(--accent-soft)}
.article-link .arrow{color:var(--accent);font-weight:700;flex:0 0 auto}
.secondary-link{display:inline-flex;margin-top:18px;color:var(--accent);font-weight:700;text-decoration:none}
.secondary-link:hover{text-decoration:underline}

body.viewer-body{display:block;align-items:stretch;padding:18px}
.viewer-shell{position:relative;width:min(100%,1180px);margin:0 auto;padding:22px;border-radius:24px;background:linear-gradient(180deg,rgba(255,255,255,0.88),rgba(255,255,255,0.76));border:1px solid var(--border);box-shadow:0 30px 80px var(--shadow);backdrop-filter:blur(10px)}
[data-theme="dark"] .viewer-shell{background:linear-gradient(180deg,rgba(15,23,42,0.92),rgba(15,23,42,0.72));backdrop-filter:blur(12px)}
.viewer-toolbar{display:flex;flex-wrap:wrap;gap:12px;align-items:flex-end;justify-content:space-between;padding-right:48px;margin-bottom:12px}
.viewer-heading{display:grid;gap:4px;min-width:min(100%,280px)}
.viewer-heading h1{margin:0;font-size:clamp(1.35rem,3vw,1.9rem);line-height:1.15}
.viewer-actions{display:flex;flex-wrap:wrap;gap:8px}
.viewer-status{margin:0 0 12px;font-size:0.92rem}
.viewer-frame-wrap{overflow:hidden;border-radius:16px;border:1px solid var(--border);background:#fff;min-height:420px}
.viewer-frame-wrap iframe{display:block;width:100%;height:min(78vh,760px);min-height:420px;border:0;background:#fff}

@media(max-width:520px){body{padding:20px}.page{padding:24px;border-radius:22px}.hero{grid-template-columns:1fr;text-align:center;justify-items:center}.avatar-wrap{margin:0 auto}.title-group{align-items:center}.intro{max-width:32ch}.highlights{justify-content:center}.links{margin-top:20px}.link-card:not(.primary-cta){flex:0 0 calc((100% - 24px) / 3);max-width:calc((100% - 24px) / 3)}.modal-panel{padding:22px;border-radius:20px}.article-link{align-items:flex-start}.presentation-card{grid-template-columns:1fr}.presentation-card img{aspect-ratio:16/10;height:auto}.action-row{display:grid;grid-template-columns:1fr 1fr}body.viewer-body{padding:12px}.viewer-shell{padding:16px;border-radius:20px}.viewer-toolbar{padding-right:0}.viewer-actions{width:100%}.viewer-actions .action-button{flex:1 1 calc(50% - 4px)}.viewer-frame-wrap iframe{height:min(70vh,560px)}}