:root {
    --bg: #1f2226;
    --bg-2: #262a2f;
    --card: #2d3238;
    --line: #3a4048;
    --text: #e6eaf0;
    --muted: #9aa5b4;
    --slate: #728ca6;
    --pale: #cce4f8;
    --teal: #00d7c2;
    --teal-dark: #00a996;
    --green: #2fcc63;
    --radius: 6px;
    --font: "Segoe UI", system-ui, -apple-system, Roboto, "Helvetica Neue", sans-serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; font-family: var(--font); background: var(--bg); color: var(--text); line-height: 1.55; -webkit-font-smoothing: antialiased; }
a { color: var(--teal); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; height: auto; display: block; }
.wrap { width: min(1120px, 100% - 40px); margin: 0 auto; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 12px; z-index: 20; padding: 8px 14px; border-radius: var(--radius); background: var(--teal); color: #0b1a18; font-weight: 600; }

/* Header */
.top { position: sticky; top: 0; z-index: 10; background: rgba(31, 34, 38, .92); backdrop-filter: blur(8px); border-bottom: 1px solid var(--line); }
.top .wrap { display: flex; align-items: center; gap: 28px; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--text); font-weight: 700; font-size: 20px; letter-spacing: .2px; }
.brand:hover { text-decoration: none; }
.brand img { width: 34px; height: 34px; }
nav.main { display: flex; gap: 22px; margin-left: 12px; }
nav.main a { color: var(--muted); font-size: 15px; }
nav.main a:hover { color: var(--text); text-decoration: none; }
.account { margin-left: auto; display: flex; align-items: center; gap: 10px; }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 10px 18px; border-radius: var(--radius); font-family: inherit; font-weight: 600; font-size: 15px; border: 1px solid transparent; white-space: nowrap; cursor: pointer; }
.btn:hover { text-decoration: none; }
.btn-primary { background: var(--teal); color: #0b1a18; }
.btn-primary:hover { background: #33e3d1; }
.btn-ghost { color: var(--text); border-color: var(--line); background: transparent; }
.btn-ghost:hover { border-color: var(--slate); background: var(--bg-2); }
.btn-link { color: var(--muted); padding: 10px 6px; }
.btn-link:hover { color: var(--text); }
.btn-lg { padding: 14px 26px; font-size: 16px; }

/* Hero */
/* The text sits over a looping video of the editor (partials/hero-video): the gradient darkens the text side
   and fades the bottom into the page. */
.hero { position: relative; isolation: isolate; overflow: hidden; padding: 112px 0 128px; }
.hero .wrap > div { max-width: 600px; }
.hero-video { position: absolute; inset: 0; z-index: -1; background: var(--bg); }
.hero-video video { width: 100%; height: 100%; object-fit: cover; display: block; }
.hero-video::after { content: ""; position: absolute; inset: 0; background: linear-gradient(180deg, rgba(31, 34, 38, 0) 72%, var(--bg)), linear-gradient(90deg, rgba(31, 34, 38, .95) 0, rgba(31, 34, 38, .9) 38%, rgba(31, 34, 38, .74) 60%, rgba(31, 34, 38, .2) 100%); }
.hero-pause { position: absolute; right: 20px; bottom: 20px; width: 36px; height: 36px; display: grid; place-items: center; border-radius: 50%; border: 1px solid rgba(204, 228, 248, .25); background: rgba(31, 34, 38, .6); color: var(--pale); cursor: pointer; opacity: .7; }
.hero-pause:hover, .hero-pause:focus-visible { opacity: 1; }
.hero-pause::before { content: ""; width: 10px; height: 12px; border: solid currentColor; border-width: 0 3px; }
.hero-pause.paused::before { width: 0; margin-left: 3px; border-width: 6px 0 6px 10px; border-color: transparent currentColor; }
.eyebrow { display: inline-block; color: var(--teal); font-weight: 600; font-size: 13px; letter-spacing: 1.6px; text-transform: uppercase; margin-bottom: 14px; }
h1 { font-size: clamp(34px, 4.6vw, 54px); line-height: 1.08; margin: 0 0 18px; letter-spacing: -.5px; }
h1 em { font-style: normal; color: var(--pale); }
.lead { font-size: 19px; color: var(--muted); margin: 0 0 30px; max-width: 34em; }
.cta { display: flex; gap: 12px; flex-wrap: wrap; }
.note { margin-top: 14px; color: var(--muted); font-size: 14px; }
.shot { border: 1px solid var(--line); border-radius: 8px; overflow: hidden; box-shadow: 0 30px 60px -30px rgba(0, 0, 0, .8), 0 0 0 1px rgba(0, 215, 194, .12); background: #111; }

/* Sections */
section { padding: 72px 0; }
section + section { border-top: 1px solid var(--line); }
h2 { font-size: clamp(26px, 3vw, 34px); margin: 0 0 12px; letter-spacing: -.3px; }
.sub { color: var(--muted); font-size: 17px; margin: 0 0 36px; max-width: 42em; }
.two { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.two p { color: var(--muted); font-size: 16px; }
.two p strong { color: var(--text); }
.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px 22px 20px; }
.card .ic { width: 38px; height: 38px; border-radius: 6px; display: grid; place-items: center; background: rgba(0, 215, 194, .12); color: var(--teal); margin-bottom: 14px; }
.card h3 { margin: 0 0 6px; font-size: 17px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; counter-reset: s; }
.step { position: relative; padding: 26px 22px 22px; background: var(--bg-2); border: 1px solid var(--line); border-radius: var(--radius); }
.step::before { counter-increment: s; content: counter(s); position: absolute; top: -14px; left: 18px; width: 28px; height: 28px; border-radius: 50%; background: var(--teal); color: #0b1a18; font-weight: 700; display: grid; place-items: center; font-size: 14px; }
.step h3 { margin: 0 0 6px; font-size: 17px; }
.step p { margin: 0; color: var(--muted); font-size: 15px; }
.tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.tag { font-size: 13px; color: var(--pale); background: rgba(114, 140, 166, .18); border: 1px solid rgba(114, 140, 166, .35); border-radius: 999px; padding: 4px 11px; }
.band { background: linear-gradient(90deg, rgba(0, 215, 194, .16), rgba(114, 140, 166, .16)); border: 1px solid var(--line); border-radius: 10px; padding: 36px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.band h2 { margin: 0 0 4px; font-size: 26px; }
.band p { margin: 0; color: var(--muted); }

/* Footer */
footer { border-top: 1px solid var(--line); padding: 28px 0 36px; color: var(--muted); font-size: 14px; }
footer .wrap { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; align-items: center; }
footer a { color: var(--muted); }
footer a:hover { color: var(--text); }

@media (max-width: 860px) {
    /* Text on top, the video shows through below the buttons. */
    .hero { padding: 48px 0 200px; }
    .hero-video::after { background: linear-gradient(180deg, rgba(31, 34, 38, .92) 0, rgba(31, 34, 38, .88) calc(100% - 290px), rgba(31, 34, 38, .25) calc(100% - 130px), var(--bg) 100%); }
    .two { grid-template-columns: 1fr; }
    .grid, .steps { grid-template-columns: 1fr; }
    nav.main { display: none; }
    .band { flex-direction: column; align-items: flex-start; }
    .hide-sm { display: none; }
}
@media (max-width: 600px) {
    /* The hero has the editor button; keep the header to brand + account. */
    .account .btn-ghost { display: none; }
    .account .btn { padding: 8px 12px; font-size: 14px; }
    .top .wrap { gap: 12px; }
}
    

/* Auth + account */
.auth { padding: 64px 0 88px; }
.auth .box { width: min(440px, 100%); margin: 0 auto; background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 32px; }
/* Sign-up: the account fields beside the plan picker; one column on narrow screens. */
.auth .box-wide { width: min(940px, 100%); padding: 36px 40px; }
.register { display: grid; grid-template-columns: 1fr 1fr; gap: 0 40px; align-items: start; }
.register .plans { margin-top: 0; }
@media (max-width: 760px) {
    .auth .box-wide { padding: 32px; }
    .register { grid-template-columns: 1fr; }
}
.auth h1, .me h1 { font-size: 28px; margin: 0 0 6px; letter-spacing: -.3px; }
.auth .sub, .panel .sub { font-size: 15px; margin-bottom: 22px; }
.field { margin-bottom: 16px; }
.field label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 6px; }
.field input { width: 100%; padding: 11px 12px; background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius); color: var(--text); font: inherit; font-size: 15px; }
.field input::placeholder { color: #6b7684; }
.field input:focus { outline: none; border-color: var(--teal); box-shadow: 0 0 0 3px rgba(0, 215, 194, .18); }
.field.invalid input { border-color: #ff7b7b; }
.field .err { color: #ff9b9b; font-size: 13px; margin: 6px 0 0; }
.field textarea { width: 100%; padding: 11px 12px; background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius); color: var(--text); font: inherit; font-size: 15px; resize: vertical; }
.field textarea:focus { outline: none; border-color: var(--teal); box-shadow: 0 0 0 3px rgba(0, 215, 194, .18); }
.field input:disabled { opacity: .45; }
.field input[type=checkbox] { width: auto; padding: 0; accent-color: var(--teal); }
.field-check { margin: -8px 0 16px; }
@media print {
  header.top, footer, .tabs, .me h1, .alert, .no-print { display: none !important; }
  body, .panel { background: #fff !important; color: #000 !important; border: 0 !important; box-shadow: none !important; }
  .table th, .table td { color: #000 !important; border-color: #999 !important; }
}
.check { display: flex; align-items: center; gap: 8px; font-size: 14px; color: var(--muted); }
.check input { accent-color: var(--teal); }
.row { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-bottom: 20px; }
.row a { font-size: 14px; }
.btn-block { width: 100%; }
.alert { padding: 12px 14px; border-radius: var(--radius); font-size: 14px; margin-bottom: 18px; }
.alert-ok { background: rgba(47, 204, 99, .14); border: 1px solid rgba(47, 204, 99, .4); color: #a6f0bc; }
.auth .foot { text-align: center; color: var(--muted); font-size: 14px; margin: 22px 0 0; }
.me { padding: 56px 0 88px; }
.me .wrap { width: min(680px, 100% - 40px); }
.me h1 { margin-bottom: 20px; }
.panel { background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 26px 28px; margin-bottom: 18px; }
.panel h2 { font-size: 20px; margin: 0 0 4px; }
.panel .cta { align-items: center; }

.projects { width: 100%; border-collapse: collapse; font-size: 14px; }
.projects th { text-align: left; color: var(--muted); font-weight: 600; padding: 6px 8px 8px 0; border-bottom: 1px solid var(--line); }
.projects td { padding: 10px 8px 10px 0; border-bottom: 1px solid var(--line); }
.projects tr:last-child td { border-bottom: 0; }

/* Dashboard (admins and professors) */
.dash .wrap { width: min(1000px, 100% - 40px); }
.dash .panel.narrow, .field-narrow { max-width: 560px; }
/* The account page as a dashboard tab: profile and password side by side. */
.panel-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 0 18px; align-items: start; }
.dash .inline-form .field { max-width: 480px; }
@media (max-width: 760px) {
    .panel-pair { grid-template-columns: 1fr; }
}
.tabs { display: flex; gap: 4px; flex-wrap: wrap; margin: 0 0 22px; border-bottom: 1px solid var(--line); }
.tabs a { padding: 10px 14px; color: var(--muted); font-weight: 600; font-size: 15px; border-bottom: 2px solid transparent; margin-bottom: -1px; }
.tabs a:hover { color: var(--text); text-decoration: none; }
.tabs a.on { color: var(--teal); border-color: var(--teal); }
.panel-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 16px; flex-wrap: wrap; }
.panel-head h2, .panel-head .sub { margin-bottom: 4px; }
.panel .sub { margin-bottom: 14px; font-size: 15px; }
.panel-head + table, .panel-head + .sub { margin-top: 14px; }
.count { color: var(--muted); font-weight: 500; font-size: 15px; margin-left: 6px; }
.table { width: 100%; border-collapse: collapse; font-size: 14px; }
.table th { text-align: left; color: var(--muted); font-weight: 600; padding: 6px 8px 8px 0; border-bottom: 1px solid var(--line); }
.table td { padding: 10px 8px 10px 0; border-bottom: 1px solid var(--line); vertical-align: middle; }
.table tr:last-child td { border-bottom: 0; }
.actions { white-space: nowrap; text-align: right; }
.actions a, .actions form { display: inline; margin-left: 12px; }
.link-danger, .btn.danger { color: #ff9b9b; }
.link-danger, .link { background: none; border: 0; padding: 0; font: inherit; cursor: pointer; }
.link { color: var(--teal); }
.link:hover { text-decoration: underline; }
.link-danger:hover { text-decoration: underline; }
.badge { display: inline-block; padding: 2px 8px; border-radius: 999px; font-size: 12px; font-weight: 600; vertical-align: middle; background: var(--bg-2); color: var(--muted); }
.badge-admin { background: rgba(0, 215, 194, .16); color: var(--teal); }
.badge-professor { background: rgba(204, 228, 248, .16); color: var(--pale); }
.facts { display: grid; grid-template-columns: max-content 1fr; gap: 6px 18px; margin: 0; font-size: 15px; }
.facts dt { color: var(--muted); }
.facts dd { margin: 0; }
.field select { width: 100%; padding: 11px 12px; background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius); color: var(--text); font: inherit; font-size: 15px; }
.checks { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 8px 16px; }
.checks label { display: flex; align-items: center; gap: 8px; font-weight: 500; font-size: 15px; }
.muted { color: var(--muted); }
.field .hint { color: var(--muted); font-size: 13px; margin: 6px 0 0; }
/* Lists grouped by class */
.group-title { display: flex; align-items: baseline; gap: 12px; margin: 26px 0 4px; font-size: 16px; }
.group-title a { font-size: 13px; font-weight: 500; }
.class-group { border: 1px solid var(--line); border-radius: var(--radius); padding: 8px 14px 14px; margin: 0 0 12px; }
.class-group legend { padding: 0 6px; font-weight: 600; }
.class-group legend label { display: flex; align-items: center; gap: 8px; }

/* A project's resources, for the professor to check */
.resources { display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 14px; }
.resource { margin: 0; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.resource .preview { height: 140px; display: grid; place-items: center; background: repeating-conic-gradient(var(--bg) 0 25%, var(--bg-2) 0 50%) 0 0 / 16px 16px; }
.resource .preview .sub { margin: 0; }
.resource img, .resource video { max-width: 100%; max-height: 140px; object-fit: contain; image-rendering: pixelated; }
.resource audio { width: 92%; }
.resource figcaption { display: flex; align-items: center; gap: 8px; padding: 8px 10px; font-size: 13px; }
.resource figcaption > span:first-child { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* Public gallery */
.alert-warn { background: rgba(255, 196, 0, .12); border: 1px solid rgba(255, 196, 0, .4); color: #ffe08a; }
.gallery { padding: 56px 0 88px; }
.gallery h1 { font-size: 34px; margin: 0 0 8px; }
.games { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 18px; }
.game-card { display: flex; flex-direction: column; gap: 2px; padding-bottom: 12px; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; color: var(--text); }
.game-card:hover { text-decoration: none; border-color: var(--teal); }
.game-card img { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; background: #111; margin-bottom: 8px; }
.game-card strong, .game-card span { padding: 0 12px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.game-card span { color: var(--muted); font-size: 14px; }
.gallery-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 24px; }
.carousel { position: relative; }
.carousel-track { display: grid; grid-auto-flow: column; grid-auto-columns: calc((100% - 3 * 18px) / 4); gap: 18px; overflow-x: auto; scroll-snap-type: x mandatory; scrollbar-width: none; }
.carousel-track::-webkit-scrollbar { display: none; }
.carousel-track .game-card { scroll-snap-align: start; }
.carousel-btn { position: absolute; top: 50%; z-index: 1; transform: translateY(-50%); width: 40px; height: 40px; border-radius: 50%; border: 1px solid var(--line); background: rgba(31, 34, 38, .92); color: var(--text); font-size: 24px; line-height: 1; cursor: pointer; }
.carousel-btn[data-step="-1"] { left: -20px; }
.carousel-btn[data-step="1"] { right: -20px; }
.carousel-btn:hover { border-color: var(--teal); color: var(--teal); }
.carousel.static .carousel-btn { display: none; }
.pager { display: flex; justify-content: center; align-items: center; gap: 18px; margin-top: 28px; }
.play { padding: 32px 0 72px; }
.player { display: block; margin: 0 auto 20px; background: #000; border: 1px solid var(--line); border-radius: 8px; overflow: hidden; }
.player iframe { display: block; width: 100%; height: 100%; border: 0; }
.game-info { display: flex; justify-content: space-between; align-items: flex-start; gap: 16px; }
.game-info h1 { font-size: 30px; margin: 0 0 2px; }
.game-info p { margin: 0; }
.game-tags { margin-top: 12px; }
.tag-category { color: var(--teal); border-color: var(--teal); }
.table .game-tags { gap: 4px; margin-top: 6px; }
.table .tag { font-size: 12px; padding: 1px 8px; }
.game-description { color: var(--muted); max-width: 46em; }
.thumb { width: 96px; aspect-ratio: 16 / 9; object-fit: cover; border-radius: 4px; background: #111; }
details.decline { display: inline-block; margin-left: 12px; text-align: left; }
details.decline summary { display: inline; list-style: none; cursor: pointer; }
details.decline summary::-webkit-details-marker { display: none; }
details.decline form { display: flex; gap: 8px; margin: 8px 0 0; }
details.decline input { width: 220px; padding: 7px 9px; background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius); color: var(--text); font: inherit; font-size: 14px; }
details.decline .btn { padding: 7px 12px; font-size: 14px; }
@media (max-width: 860px) {
    .carousel-track { grid-auto-columns: calc((100% - 18px) / 2); }
    .carousel-btn { display: none; }
    .gallery-head { flex-direction: column; gap: 0; }
}
@media (max-width: 600px) {
    .carousel-track { grid-auto-columns: 80%; }
}

/* Teacher's toolbox on the home pages (partials/teacher-tour) */
.teach { background: radial-gradient(900px 420px at 100% 0%, rgba(0, 215, 194, .10), transparent 60%), radial-gradient(700px 380px at 0% 100%, rgba(114, 140, 166, .14), transparent 60%); }
.tour { display: grid; grid-template-columns: 330px 1fr; gap: 28px; align-items: start; }
.tour-tabs { display: flex; flex-direction: column; gap: 8px; }
.tour-tabs button { text-align: left; padding: 13px 16px; background: var(--card); border: 1px solid var(--line); border-left: 3px solid var(--line); border-radius: var(--radius); color: var(--text); font: inherit; cursor: pointer; }
.tour-tabs button:hover { border-color: var(--slate); }
.tour-tabs button[aria-selected="true"] { border-color: rgba(0, 215, 194, .45); border-left-color: var(--teal); background: #323941; }
.tour-tabs strong { display: block; font-size: 16px; }
.tour-tabs button[aria-selected="true"] strong { color: var(--teal); }
.tour-tabs span { display: block; margin-top: 2px; color: var(--muted); font-size: 14px; line-height: 1.45; }
.tour figure { margin: 0; }
.teach .grid { margin-top: 40px; }
.teach .cta { margin-top: 32px; }
@media (max-width: 860px) {
    /* No tabs on phones: every tool, then its screenshot. */
    .tour { display: flex; flex-direction: column; gap: 10px; }
    .tour-tabs { display: contents; }
    .tour-tabs button, .tour-tabs button[aria-selected="true"] { cursor: default; border-color: var(--line); border-left-color: var(--teal); background: var(--card); }
    .tour-tabs button[aria-selected="true"] strong { color: var(--text); }
    .tour figure[hidden] { display: block; }
    .tour figure { margin-bottom: 14px; }
}

/* Premium: the sign-up plans (auth/_plans), the subscription page (billing) and the past-due alert */
.plans { border: 0; padding: 0; margin: 4px 0 20px; display: grid; gap: 8px; }
.plans legend { font-size: 14px; font-weight: 600; margin-bottom: 6px; padding: 0; }
.plan { display: flex; align-items: center; gap: 12px; padding: 12px 14px; background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius); cursor: pointer; }
.plan:has(input:checked) { border-color: var(--teal); box-shadow: 0 0 0 3px rgba(0, 215, 194, .18); }
.plan input { accent-color: var(--teal); margin: 0; }
.plan > span:first-of-type { flex: 1; display: grid; gap: 2px; font-size: 15px; }
.plan small { color: var(--muted); font-size: 13px; font-weight: 400; }
.plan .price { font-weight: 700; white-space: nowrap; }
.perks { margin-top: 4px; padding: 12px 14px; border-radius: var(--radius); background: rgba(0, 215, 194, .07); border: 1px solid rgba(0, 215, 194, .25); font-size: 14px; }
.perks p { margin: 0; }
.perks ul, .perk-list { margin: 6px 0 8px; padding-left: 20px; display: grid; gap: 4px; }
.perks .hint { color: var(--muted); font-size: 13px; }
.perk-list { margin: 0 0 18px; font-size: 15px; }
.inline-form { display: flex; align-items: flex-end; gap: 12px; flex-wrap: wrap; }
.inline-form .field { flex: 1 1 260px; margin-bottom: 0; }
.alert-danger { background: rgba(255, 123, 123, .12); border: 1px solid rgba(255, 123, 123, .45); color: #ffb3b3; }
.alert-danger a { color: #fff; font-weight: 600; }
.nowrap { white-space: nowrap; }