:root { --color-bg: #f5f7f4; --color-surface: #ffffff; --color-border: #dde5dd; --color-text: #1c241e; --color-muted: #5c6b5e; --color-primary: #1e4d2b; --color-primary-2: #2c6e3f; --color-accent: #c8c372; --color-accent-bg: #eef3ea; --color-locked-bg: #ecefe9; --color-locked-text: #6b7768; --color-open-bg: #e3f0e6; --color-open-text: #1e4d2b; --radius: 8px; --maxw: 1100px; --shadow: 0 1px 3px rgba(28, 36, 30, 0.10); }

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body { margin: 0; background: var(--color-bg); color: var(--color-text); font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }

a { color: var(--color-primary-2); text-decoration: none; }

a:hover { text-decoration: underline; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 1.25rem; }

/* ---- Header / nav ---- */
.site-header { background: var(--color-primary); color: #fff; box-shadow: var(--shadow); }

.site-header .wrap { padding-top: 1rem; padding-bottom: 1rem; }

.brand { display: flex; align-items: center; gap: 0.85rem; }

.brand-logo-link { display: inline-flex; flex: 0 0 auto; }

.brand-logo { height: 52px; width: 52px; display: block; background: #fff; border-radius: 10px; padding: 4px; box-shadow: var(--shadow); }

.brand-text { display: flex; flex-direction: column; }

.site-title { font-size: 1.25rem; font-weight: 700; color: #fff; display: block; }

.site-title:hover { text-decoration: none; opacity: 0.92; }

.site-tagline { font-size: 0.9rem; color: #cfe0f0; margin-top: 2px; }

.site-nav { margin-top: 0.75rem; display: flex; flex-wrap: wrap; gap: 0.25rem 1.1rem; }

.site-nav a { color: #e8f0f8; font-size: 0.92rem; padding: 0.2rem 0; border-bottom: 2px solid transparent; }

.site-nav a:hover { color: #fff; text-decoration: none; border-bottom-color: var(--color-accent); }

.site-nav a.active { color: #fff; border-bottom-color: var(--color-accent); font-weight: 600; }

/* ---- Main ---- */
main { padding: 2rem 0 3rem; }

main .wrap > h1:first-child { margin-top: 0; }

h1, h2, h3 { color: var(--color-primary); line-height: 1.25; }

h1 { font-size: 1.9rem; }

h2 { font-size: 1.4rem; margin-top: 2rem; border-bottom: 1px solid var(--color-border); padding-bottom: 0.3rem; }

.lead { font-size: 1.1rem; color: var(--color-muted); }

.owner-byline { display: inline-block; margin: 0.25rem 0 1.5rem; padding: 0.5rem 0.9rem; background: var(--color-accent-bg); border-left: 4px solid var(--color-accent); border-radius: var(--radius); font-size: 0.98rem; color: var(--color-text); }

/* ---- Tables ---- */
table { width: 100%; border-collapse: collapse; background: var(--color-surface); box-shadow: var(--shadow); border-radius: var(--radius); overflow: hidden; margin: 1rem 0 2rem; }

th, td { text-align: left; padding: 0.6rem 0.8rem; border-bottom: 1px solid var(--color-border); vertical-align: top; }

th { background: var(--color-primary); color: #fff; font-size: 0.85rem; letter-spacing: 0.02em; text-transform: uppercase; }

tbody tr:nth-child(even) { background: var(--color-accent-bg); }

tbody tr:hover { background: #dcebf6; }

/* ---- Cards / callouts ---- */
.callout { background: var(--color-accent-bg); border-left: 4px solid var(--color-accent); border-radius: var(--radius); padding: 0.9rem 1.1rem; margin: 1.5rem 0; }

.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 1rem; margin: 1.5rem 0; }

.card { background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius); padding: 1rem 1.1rem; box-shadow: var(--shadow); }

.card h3 { margin-top: 0; font-size: 1.05rem; }

/* ---- Buttons ---- */
.btn { display: inline-block; background: var(--color-primary); color: #fff; padding: 0.5rem 1rem; border-radius: var(--radius); font-weight: 600; font-size: 0.95rem; }

.btn:hover { background: var(--color-primary-2); text-decoration: none; }

.btn-ghost { background: transparent; color: var(--color-primary); border: 1px solid var(--color-primary); }

.btn-ghost:hover { background: var(--color-accent-bg); color: var(--color-primary); }

/* ---- Lock badges for assessments ---- */
.badge { display: inline-block; font-size: 0.75rem; font-weight: 700; padding: 0.15rem 0.55rem; border-radius: 999px; letter-spacing: 0.02em; }

.badge-locked { background: var(--color-locked-bg); color: var(--color-locked-text); }

.badge-open { background: var(--color-open-bg); color: var(--color-open-text); }

.assess-list { list-style: none; padding: 0; margin: 1.5rem 0; }

.assess-list li { display: flex; align-items: center; gap: 0.75rem; flex-wrap: wrap; background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius); padding: 0.8rem 1rem; margin-bottom: 0.6rem; box-shadow: var(--shadow); }

.assess-list .a-title { font-weight: 600; }

.assess-list .a-meta { color: var(--color-muted); font-size: 0.9rem; }

.assess-list .a-spacer { flex: 1 1 auto; }

.assess-list .locked .a-title { color: var(--color-muted); }

/* ---- Lecture prev/next nav ---- */
.lecture-nav { display: flex; align-items: center; gap: 1rem; flex-wrap: wrap; margin-top: 2.5rem; padding-top: 1rem; border-top: 1px solid var(--color-border); font-size: 0.92rem; }

.lecture-nav .ln-prev { flex: 1 1 0; }

.lecture-nav .ln-up { flex: 0 0 auto; color: var(--color-muted); }

.lecture-nav .ln-next { flex: 1 1 0; text-align: right; }

/* ---- Footer ---- */
.site-footer { border-top: 1px solid var(--color-border); background: var(--color-surface); color: var(--color-muted); font-size: 0.85rem; padding: 1.5rem 0; }

.site-footer .wrap { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 0.5rem; }

@media (max-width: 640px) { .site-footer .wrap { flex-direction: column; }
  th, td { padding: 0.5rem; font-size: 0.9rem; } }