/* The lessons of learn/ (js/learn.js): hero, the steps of the course, the board with the band, the pager. Colours from the variables of site.css and the theme. */
:root { --qfont: "QATT Pen Medium"; --row: 4.6rem; --step: 4s; --mid: 10rem; }

.hero {
  background:
    radial-gradient(60rem 22rem at 50% -6rem, color-mix(in srgb, var(--cinnabar) 10%, transparent), transparent 70%),
    linear-gradient(180deg, var(--paper, #f7efdc) 0%, var(--bs-body-bg) 100%);
  border-bottom: 1px solid color-mix(in srgb, currentColor 12%, transparent);
  color: var(--ink);
}
.hero h1 { font-family: Georgia, "Times New Roman", serif; font-weight: 400; font-size: clamp(2.2rem, 7vw, 3.4rem); letter-spacing: .01em; }
.hero .lead { max-width: 38rem; color: var(--bs-secondary-color); }
.hero .kicker { font-size: .78rem; letter-spacing: .14em; text-transform: uppercase; color: var(--cinnabar); }

.learn { max-width: 36rem; }
.learn .intro { color: var(--bs-secondary-color); }
.learn .intro b { color: var(--ink); font-weight: 600; }
.learn .qa { font-family: var(--qfont), sans-serif; font-size: 1.35em; line-height: 1; color: var(--ink); }

/* the steps of the course (#content: links in main take the colour of the theme otherwise) */
.steps { display: flex; gap: .35rem; justify-content: center; flex-wrap: wrap; margin: 0 0 1.4rem; padding: 0; list-style: none; }
#content .steps a { display: inline-flex; align-items: center; gap: .4rem; padding: .25rem .7rem .25rem .3rem; border-radius: 2rem; font-size: .82rem; text-decoration: none; color: var(--bs-secondary-color); background: color-mix(in srgb, currentColor 6%, transparent); transition: background-color .25s, color .25s; }
#content .steps a:hover { color: var(--ink); }
.steps .num { width: 1.5rem; height: 1.5rem; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; font-weight: 600; font-size: .75rem; background: color-mix(in srgb, currentColor 12%, transparent); }
.steps .done .num { background: color-mix(in srgb, var(--bs-success) 25%, transparent); color: var(--bs-success); }
#content .steps .now a { background: var(--cinnabar); color: #fff; }
.steps .now .num { background: rgba(255, 255, 255, .25); color: #fff; }
#learnSteps .steps .t { display: none; }   /* only the numbers (the name is the title); the phone shows the name of the current lesson */
.steps .home .num { font-size: .8rem; }
@media (max-width: 576px) { .steps { flex-wrap: nowrap; gap: .2rem; } .steps li:not(.now) .t { display: none; } #learnSteps .steps .now .t { display: inline; } .steps a { padding-right: .3rem; } .steps .now a { padding-right: .7rem; } }

/* the tabs: a row (or rows: .rows, tabRows of Learn.board) with a sliding pill behind the active one */
.marks.rows { grid-auto-flow: row; }
.tools { flex-wrap: wrap; }
.marks { position: relative; display: grid; grid-auto-flow: column; grid-auto-columns: 1fr; gap: .25rem; padding: .3rem; border-radius: 1.1rem; background: color-mix(in srgb, currentColor 6%, transparent); color: var(--ink); }
.marks .pill { position: absolute; top: 0; left: 0; width: 0; height: 0; border-radius: .85rem; background: var(--cinnabar); box-shadow: 0 .35rem 1rem color-mix(in srgb, var(--cinnabar) 40%, transparent); transition: transform .55s cubic-bezier(.65, 0, .35, 1), width .55s cubic-bezier(.65, 0, .35, 1), height .55s cubic-bezier(.65, 0, .35, 1); z-index: 0; }
.marks button { position: relative; z-index: 1; display: flex; flex-direction: column; align-items: center; gap: .05rem; padding: .35rem .2rem .3rem; border: 0; border-radius: .85rem; background: none; color: inherit; transition: color .35s; min-width: 0; }
.marks button:hover { color: var(--cinnabar); }
.marks button.active { color: #fff; }
.marks .g { font-family: var(--qfont), sans-serif; font-size: 1.7rem; line-height: 1.1; }
.marks .n { font-size: .72rem; letter-spacing: .04em; opacity: .85; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; max-width: 100%; }
.progress-line { height: 3px; margin: .55rem .9rem 0; border-radius: 3px; background: color-mix(in srgb, currentColor 10%, transparent); overflow: hidden; color: var(--ink); }
.progress-line > div { height: 100%; width: 0; background: var(--cinnabar); transition: width .9s cubic-bezier(.65, 0, .35, 1); }

/* the board: rows of two items with their readings in the middle (muted); the band lies across the row being read, which is shown fully */
.board { position: relative; padding: .6rem 0; color: var(--ink); }
.row-pair { scroll-margin: 5rem 0 6rem; position: relative; z-index: 1; display: grid; grid-template-columns: 1fr var(--mid) 1fr; align-items: center; height: var(--row); cursor: pointer; }
.row-pair .g { display: flex; align-items: center; justify-content: center; gap: .3rem; font-family: var(--qfont), sans-serif; font-size: 3.1rem; line-height: 1; transition: color .6s, transform .6s cubic-bezier(.34, 1.56, .64, 1), opacity .6s; opacity: .7; }
.row-pair .g .part { font-size: 2.3rem; }
.row-pair .g .plus { font-family: Georgia, serif; font-size: 1.1rem; opacity: .6; }
.row-pair.apart::after { content: ""; position: absolute; left: 12%; right: 12%; bottom: 0; border-bottom: 1px solid color-mix(in srgb, currentColor 20%, transparent); }   /* the first row of a tab with apart (the rhymes: stroke 1, always ông) */
.row-pair.now .g { opacity: 1; color: var(--cinnabar); transform: scale(1.15); }
.row-pair:hover .g { opacity: .9; }
.row-pair.in .g { animation: glyphIn .55s cubic-bezier(.2, .8, .2, 1) both; animation-delay: calc(var(--i) * 35ms); }
@keyframes glyphIn { from { opacity: 0; transform: translateY(.5rem) scale(.85); filter: blur(4px); } }

.band { position: absolute; z-index: 2; left: .5rem; right: .5rem; top: .6rem; height: var(--row); pointer-events: none; border-radius: 1.2rem;
  background: linear-gradient(90deg, color-mix(in srgb, var(--cinnabar) 9%, transparent), color-mix(in srgb, var(--cinnabar) 16%, transparent) 50%, color-mix(in srgb, var(--cinnabar) 9%, transparent));
  border: 1px solid color-mix(in srgb, var(--cinnabar) 35%, transparent);
  box-shadow: 0 .6rem 1.6rem -.6rem color-mix(in srgb, var(--cinnabar) 45%, transparent), inset 0 1px 0 color-mix(in srgb, #fff 45%, transparent);
  transition: transform .9s cubic-bezier(.65, 0, .35, 1); overflow: hidden; }
.row-pair .pair { display: flex; justify-content: center; align-items: center; gap: .5rem; font-family: Georgia, "Times New Roman", serif; white-space: nowrap; color: var(--ink); opacity: .5; transition: opacity .6s; }
.row-pair .pair .dot { color: var(--cinnabar); opacity: .7; }
.row-pair .r { display: flex; flex-direction: column; align-items: center; line-height: 1.1; }
.row-pair .r .big { font-size: 1.5rem; }
.row-pair .r .small { font-family: var(--bs-body-font-family); font-size: .68rem; letter-spacing: .03em; color: var(--bs-secondary-color); }
.row-pair.now .pair { opacity: 1; }
.row-pair .pair.in .r { animation: sayIn .5s cubic-bezier(.2, .8, .2, 1) both; }
.row-pair .pair.in .r:last-child { animation-delay: .12s; }
@keyframes sayIn { from { opacity: .3; transform: translateY(.4rem); } }
.band .tick { position: absolute; left: 0; bottom: 0; height: 2px; width: 100%; transform-origin: left; transform: scaleX(0); background: var(--cinnabar); opacity: .55; }
.band .tick.run { animation: tick var(--step) linear forwards; }
@keyframes tick { to { transform: scaleX(1); } }
.band .speaking { position: absolute; top: 50%; right: 1rem; transform: translateY(-50%); color: var(--cinnabar); opacity: 0; transition: opacity .3s; }
.band.voice .speaking { opacity: .8; }

.play { width: 3.2rem; height: 3.2rem; padding: 0; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; font-size: 1.5rem; }
.round { width: 2.4rem; height: 2.4rem; padding: 0; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; font-size: 1.15rem; }
.hint { font-size: .85rem; color: var(--bs-secondary-color); }

/* the pager at the end of a lesson */
.pager { display: flex; justify-content: space-between; align-items: center; gap: .5rem; margin-top: 2.5rem; padding-top: 1.2rem; border-top: 1px solid color-mix(in srgb, currentColor 12%, transparent); }
.pager .btn { display: inline-flex; align-items: center; gap: .4rem; }

/* lessons that are not written yet (soon: true in js/learn.js) */
.steps .soon:not(.now) a { opacity: .55; }
#content .lesson-card.soon { opacity: .6; }
#content .lesson-card.soon:hover { opacity: .85; }
.badge-soon { margin-left: .5rem; padding: .05rem .45rem; border-radius: 1rem; font-size: .62rem; letter-spacing: .06em; background: color-mix(in srgb, var(--cinnabar) 15%, transparent); color: var(--cinnabar); }
.soon-box { text-align: center; padding: 2.2rem 1.2rem; color: var(--ink); }
.soon-box .bi { font-size: 2.2rem; color: var(--cinnabar); }
.soon-box h2 { font-family: Georgia, "Times New Roman", serif; font-weight: 400; font-size: 1.6rem; margin: .6rem 0 .4rem; }
.soon-box p { color: var(--bs-secondary-color); max-width: 28rem; margin: 0 auto 1.2rem; }

/* lesson 6: sentences to uncover and the quiz */
.learn h2.part-title { font-family: Georgia, "Times New Roman", serif; font-weight: 400; font-size: 1.6rem; text-align: center; margin: 2.8rem 0 .4rem; color: var(--ink); }
.learn .part-lead { text-align: center; color: var(--bs-secondary-color); margin-bottom: 1.2rem; }
.sentences { display: grid; gap: .6rem; }
.sentence { display: block; width: 100%; text-align: left; padding: .9rem 1.1rem; border: 0; color: var(--ink); cursor: pointer; transition: transform .2s; }
.sentence:hover { transform: translateY(-1px); }
.sentence .q { font-family: var(--qfont), sans-serif; font-size: 2.1rem; line-height: 1.25; overflow-wrap: anywhere; }
.sentence .a { display: grid; grid-template-rows: 0fr; opacity: 0; transition: grid-template-rows .45s cubic-bezier(.2, .8, .2, 1), opacity .45s; font-family: Georgia, "Times New Roman", serif; font-size: 1.15rem; color: var(--cinnabar); }
.sentence .a > span { overflow: hidden; }
.sentence.open .a { grid-template-rows: 1fr; opacity: 1; }
.sentence .hint-tap { font-size: .75rem; color: var(--bs-secondary-color); }
.sentence.open .hint-tap { display: none; }

.quiz { text-align: center; padding: 1.6rem 1.2rem 1.4rem; color: var(--ink); }
.quiz .count { font-size: .78rem; letter-spacing: .12em; text-transform: uppercase; color: var(--bs-secondary-color); }
.quiz .dots { display: flex; justify-content: center; gap: .35rem; margin: .5rem 0 1rem; }
.quiz .dots span { width: .55rem; height: .55rem; border-radius: 50%; background: color-mix(in srgb, currentColor 15%, transparent); transition: background-color .3s, transform .3s; }
.quiz .dots .ok { background: var(--bs-success); }
.quiz .dots .no { background: var(--bs-danger); }
.quiz .dots .now { transform: scale(1.4); background: var(--cinnabar); }
.quiz .ask { font-family: var(--qfont), sans-serif; font-size: 5rem; line-height: 1.1; color: var(--ink); animation: pop .4s cubic-bezier(.34, 1.56, .64, 1) both; }
@keyframes pop { from { opacity: 0; transform: scale(.8); } }
.quiz .options { display: grid; grid-template-columns: 1fr 1fr; gap: .6rem; max-width: 22rem; margin: 1.2rem auto 0; }
.quiz .options .btn { font-family: Georgia, "Times New Roman", serif; font-size: 1.25rem; padding: .55rem .5rem; transition: background-color .25s, border-color .25s, color .25s, transform .15s; }
.quiz .options .btn.right { --bs-btn-bg: var(--bs-success); --bs-btn-border-color: var(--bs-success); --bs-btn-color: #fff; --bs-btn-disabled-bg: var(--bs-success); --bs-btn-disabled-border-color: var(--bs-success); --bs-btn-disabled-color: #fff; --bs-btn-disabled-opacity: 1; }
.quiz .options .btn.wrong { --bs-btn-bg: var(--bs-danger); --bs-btn-border-color: var(--bs-danger); --bs-btn-color: #fff; --bs-btn-disabled-bg: var(--bs-danger); --bs-btn-disabled-border-color: var(--bs-danger); --bs-btn-disabled-color: #fff; --bs-btn-disabled-opacity: 1; animation: shake .35s; }
@keyframes shake { 25% { transform: translateX(-4px); } 75% { transform: translateX(4px); } }
.quiz .result { font-family: Georgia, "Times New Roman", serif; font-size: 2.6rem; color: var(--cinnabar); }
.quiz .result-text { color: var(--bs-secondary-color); margin: .3rem 0 1.2rem; }

/* the overview */
.lessons { display: grid; gap: .9rem; max-width: 46rem; }
@media (min-width: 640px) { .lessons { grid-template-columns: 1fr 1fr; } }
#content .lesson-card { position: relative; display: flex; gap: 1rem; align-items: center; padding: 1rem 1.1rem; text-decoration: none; color: var(--ink); transition: transform .2s, box-shadow .2s; }
#content .lesson-card:hover { transform: translateY(-2px); color: var(--ink); }
.lesson-card .g { flex: 0 0 4.2rem; height: 4.2rem; display: flex; align-items: center; justify-content: center; border-radius: 1rem; font-family: var(--qfont), sans-serif; font-size: 2.4rem; color: var(--cinnabar); background: color-mix(in srgb, var(--cinnabar) 9%, transparent); }
.lesson-card .no { font-size: .72rem; letter-spacing: .12em; text-transform: uppercase; color: var(--bs-secondary-color); }
.lesson-card h2 { font-family: Georgia, "Times New Roman", serif; font-size: 1.3rem; font-weight: 400; margin: .1rem 0 .2rem; }
.lesson-card p { font-size: .85rem; margin: 0; color: var(--bs-secondary-color); }
.lesson-card .check { position: absolute; top: .7rem; right: .8rem; color: var(--bs-success); font-size: 1.1rem; }

@media (max-width: 420px) {
  :root { --row: 4rem; --mid: 8rem; }
  .row-pair .g { font-size: 2.6rem; }
  .row-pair .g .part { font-size: 1.9rem; }
  .row-pair .r .big { font-size: 1.2rem; }
  .marks .n { font-size: .62rem; }
}
@media (prefers-reduced-motion: reduce) {
  .band, .marks .pill, .row-pair .g { transition-duration: .01s; }
  .row-pair.in .g, .row-pair .pair.in .r { animation: none; }
}