/* English study site: warm Mediterranean palette, one colour per skill. */

:root {
  --bg: #fbf7f1;
  --surface: #ffffff;
  --surface-2: #f5efe6;
  --ink: #1f2337;
  --muted: #666a7e;
  --line: #ebe3d6;
  --primary: #3d5af1;
  --primary-soft: #e9edff;
  --on-k: #ffffff;
  --ok: #17865a;
  --ok-soft: #e2f5ec;
  --bad: #c93a3a;
  --bad-soft: #fdeaea;
  --warn: #9a5d06;
  --warn-soft: #fff3da;
  --shadow: 0 1px 2px rgba(31, 35, 55, .05), 0 6px 20px rgba(31, 35, 55, .06);
  --hero: linear-gradient(135deg, #3d5af1 0%, #7c4dff 52%, #ff7a59 100%);
  --word: linear-gradient(135deg, #fff5dc 0%, #ffe6dd 100%);
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14151c;
    --surface: #1d1f29;
    --surface-2: #252836;
    --ink: #eceef6;
    --muted: #a3a7ba;
    --line: #30344a;
    --primary: #8ea2ff;
    --primary-soft: #262d52;
    --on-k: #14151c;
    --ok: #6fd3a4;
    --ok-soft: #173326;
    --bad: #ff9a9a;
    --bad-soft: #3b1f22;
    --warn: #f3c56b;
    --warn-soft: #3a2f16;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 8px 24px rgba(0, 0, 0, .25);
    --hero: linear-gradient(135deg, #2c3fb8 0%, #5b34c7 52%, #b94e36 100%);
    --word: linear-gradient(135deg, #2f2817 0%, #35221d 100%);
    color-scheme: dark;
  }
}

/* one colour per skill: --k for accents, --k-soft for tinted backgrounds */
.kind-grammar { --k: #3d5af1; --k-soft: #e9edff; }
.kind-reading { --k: #17865a; --k-soft: #e2f5ec; }
.kind-listening { --k: #7c4dff; --k-soft: #efe8ff; }
.kind-writing { --k: #e0583a; --k-soft: #ffece5; }
.kind-vocabulary { --k: #0d8a80; --k-soft: #dff5f2; }
.kind-translation { --k: #b97c00; --k-soft: #fff1cc; }
.kind-speaking { --k: #d23f78; --k-soft: #fde6ef; }

@media (prefers-color-scheme: dark) {
  .kind-grammar { --k: #8ea2ff; --k-soft: #262d52; }
  .kind-reading { --k: #6fd3a4; --k-soft: #173326; }
  .kind-listening { --k: #b79bff; --k-soft: #2e2550; }
  .kind-writing { --k: #ff9e85; --k-soft: #3d241c; }
  .kind-vocabulary { --k: #5fd6cb; --k-soft: #143331; }
  .kind-translation { --k: #f2c35b; --k-soft: #3a2f12; }
  .kind-speaking { --k: #ff8fb8; --k-soft: #3e1d2b; }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 17px/1.6 var(--sans);
  -webkit-text-size-adjust: 100%;
}

h1, h2, h3 { font-family: var(--serif); line-height: 1.2; letter-spacing: -.01em; }
h1 { font-size: 30px; margin: 0 0 6px; }
h2 { font-size: 22px; margin: 0 0 12px; }
h3 { font-size: 19px; margin: 16px 0 6px; }
a { color: var(--k, var(--primary)); }
.muted { color: var(--muted); }
.error { color: var(--bad); }
.warn { color: var(--warn); }

/* ---------- header ---------- */

.top {
  position: sticky;
  top: 0;
  z-index: 5;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 10px 16px;
  background: var(--surface);
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 19px;
  font-weight: 700;
  text-decoration: none;
}
#brand-name { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.logo {
  display: grid;
  flex: none;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 11px;
  background: var(--hero);
  color: #fff;
  font-size: 18px;
}
.top-right { display: flex; flex: none; align-items: center; gap: 6px; }
.top form { margin: 0; }
.pill {
  padding: 4px 12px;
  border-radius: 999px;
  background: var(--primary-soft);
  color: var(--primary);
  font-size: 14px;
  font-weight: 700;
  white-space: nowrap;
}
.pill:empty { display: none; }

main { max-width: 860px; margin: 0 auto; padding: 20px 16px 140px; }

/* ---------- controls ---------- */

button, select, input, textarea { font: inherit; color: inherit; }
button {
  padding: 9px 16px;
  border: 1.5px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  font-weight: 600;
  cursor: pointer;
  transition: transform .1s ease, border-color .15s ease, background .15s ease;
}
button:hover:not(:disabled) { border-color: var(--k, var(--primary)); }
button:active:not(:disabled) { transform: scale(.97); }
button:disabled { opacity: .5; cursor: default; }
button.primary {
  padding: 12px 22px;
  border-color: var(--k, var(--primary));
  background: var(--k, var(--primary));
  color: var(--on-k);
}
button.primary:hover:not(:disabled) { filter: brightness(1.06); }
button.link { padding: 6px 8px; border: 0; background: none; color: var(--muted); font-size: 14px; }
button.link:hover { color: var(--ink); }
:focus-visible { outline: 3px solid var(--k, var(--primary)); outline-offset: 2px; }
select {
  max-width: 100%;
  padding: 8px 10px;
  border: 1.5px solid var(--line);
  border-radius: 12px;
  background: var(--surface-2);
}
input[type=text], input[type=password], input:not([type]), textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1.5px solid var(--line);
  border-radius: 12px;
  background: var(--surface-2);
  transition: border-color .15s ease, background .15s ease, box-shadow .15s ease;
}
input:focus, textarea:focus {
  outline: none;
  border-color: var(--k, var(--primary));
  background: var(--surface);
  box-shadow: 0 0 0 4px var(--k-soft, var(--primary-soft));
}
input.gap { display: inline-block; width: 11em; max-width: 100%; margin: 2px 4px; padding: 4px 10px; border-radius: 10px; }
textarea { display: block; min-height: 2.8em; resize: vertical; }
input:disabled, textarea:disabled { opacity: .85; }

.box {
  margin: 16px 0;
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 22px;
  box-shadow: var(--shadow);
}
.box > :first-child { margin-top: 0; }
.box > :last-child { margin-bottom: 0; }
.panel {
  margin: 24px 0;
  padding: 14px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 18px;
}
summary { cursor: pointer; font-weight: 700; }
.row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 10px; }
.icon {
  display: grid;
  flex: none;
  place-items: center;
  width: 48px;
  height: 48px;
  border-radius: 15px;
  background: var(--k-soft, var(--primary-soft));
  font-size: 24px;
}
.icon.big { width: 60px; height: 60px; border-radius: 19px; font-size: 30px; }
.bar { display: block; height: 7px; overflow: hidden; border-radius: 999px; background: var(--surface-2); }
.bar > span { display: block; width: 0; height: 100%; border-radius: inherit; background: var(--k, var(--primary)); transition: width .3s ease; }

/* ---------- home ---------- */

.hero {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 28px;
  border-radius: 26px;
  background: var(--hero);
  color: #fff;
  box-shadow: var(--shadow);
}
.hero h1 { margin: 2px 0 8px; font-size: 34px; }
.hero p { margin: 0; opacity: .93; }
.hero .eyebrow { font-size: 13px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; opacity: .85; }
.goal { display: grid; flex: none; justify-items: center; gap: 6px; }
.goal small { font-size: 13px; opacity: .9; }
.ring { position: relative; display: grid; place-items: center; width: 100px; height: 100px; font-size: 22px; font-weight: 800; }
.ring::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 50%;
  background: conic-gradient(#ffd166 calc(var(--p, 0) * 1%), rgba(255, 255, 255, .25) 0);
  -webkit-mask: radial-gradient(farthest-side, transparent calc(100% - 11px), #000 calc(100% - 10px));
  mask: radial-gradient(farthest-side, transparent calc(100% - 11px), #000 calc(100% - 10px));
}

.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; margin: 16px 0; }
.stat {
  display: grid;
  gap: 2px;
  padding: 14px 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow);
}
.stat-icon { font-size: 20px; }
.stat strong { font-family: var(--serif); font-size: 21px; }
.stat span:last-child { color: var(--muted); font-size: 13px; }

.continue {
  display: flex;
  align-items: center;
  gap: 16px;
  margin: 16px 0;
  padding: 18px 20px;
  background: linear-gradient(135deg, var(--k-soft), var(--surface) 70%);
  border: 2px solid var(--k);
  border-radius: 22px;
  color: var(--ink);
  text-decoration: none;
  box-shadow: var(--shadow);
  transition: transform .15s ease;
}
.continue:hover { transform: translateY(-2px); }
.continue-text { display: grid; flex: 1; min-width: 0; }
.continue small { color: var(--k); font-size: 12px; font-weight: 800; letter-spacing: .06em; text-transform: uppercase; }
.continue strong { font-family: var(--serif); font-size: 22px; }
.go { flex: none; padding: 10px 18px; border-radius: 999px; background: var(--k); color: var(--on-k); font-weight: 700; }

.duo { display: grid; grid-template-columns: 1.5fr 1fr; gap: 16px; }
.duo .box { margin: 0; }

.steps { position: relative; display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; margin: 0; padding: 0; list-style: none; }
.steps li { position: relative; display: grid; justify-items: center; gap: 4px; text-align: center; }
.steps li::before {
  content: "";
  position: absolute;
  top: 23px;
  right: 50%;
  width: 100%;
  height: 3px;
  background: var(--line);
}
.steps li:first-child::before { display: none; }
.steps li.done::before, .steps li.now::before { background: var(--primary); }
.step-icon {
  position: relative;
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border: 2px solid var(--line);
  border-radius: 50%;
  background: var(--surface-2);
  font-size: 21px;
}
.steps .done .step-icon { border-color: var(--primary); background: var(--primary); color: var(--surface); font-weight: 800; }
.steps .now .step-icon { border-color: var(--primary); background: var(--surface); box-shadow: 0 0 0 6px var(--primary-soft); }
.steps strong { font-size: 14px; line-height: 1.3; }
.steps small { color: var(--muted); font-size: 12px; line-height: 1.3; }

.word { background: var(--word); border-color: transparent; }
.word-head { display: flex; align-items: center; justify-content: space-between; }
.word-head small { color: #c2410c; font-size: 12px; font-weight: 800; letter-spacing: .08em; text-transform: uppercase; }
.word h3 { margin: 6px 0 2px; font-size: 28px; }
.word h3 .muted { font-family: var(--sans); font-size: 14px; font-weight: 400; }
.example { margin: 8px 0 0; font-family: var(--serif); font-size: 18px; font-style: italic; }
.icon-button { width: 40px; height: 40px; padding: 0; border: 0; background: var(--surface); font-size: 18px; }
@media (prefers-color-scheme: dark) { .word-head small { color: #ffb38a; } }

.group { margin-top: 32px; }
.group-head { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; }
.group-head h2 { margin-bottom: 12px; }
.group-head span { color: var(--muted); font-size: 14px; white-space: nowrap; }
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(min(100%, 340px), 1fr)); gap: 12px; }
.card {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 20px;
  color: var(--ink);
  text-decoration: none;
  box-shadow: var(--shadow);
  transition: transform .15s ease, border-color .15s ease;
}
.card:hover { transform: translateY(-2px); border-color: var(--k); }
.card-body { display: grid; flex: 1; gap: 5px; min-width: 0; }
.card-title { font-weight: 700; }
.card-meta { color: var(--muted); font-size: 13px; }
.chip {
  flex: none;
  align-self: flex-start;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--surface-2);
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
  white-space: nowrap;
}
.chip.busy { background: var(--k-soft); color: var(--k); }
.chip.wait { background: var(--warn-soft); color: var(--warn); }
.chip.ok { background: var(--ok-soft); color: var(--ok); }

/* ---------- unit ---------- */

.back { display: inline-block; margin-bottom: 12px; color: var(--muted); font-weight: 600; text-decoration: none; }
.back:hover { color: var(--ink); }
.unit-head {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 22px;
  background: linear-gradient(135deg, var(--k-soft), var(--surface) 75%);
  border: 1px solid var(--line);
  border-radius: 24px;
}
.unit-head small { color: var(--k); font-size: 12px; font-weight: 800; letter-spacing: .06em; text-transform: uppercase; }
.unit-head h1 { margin: 2px 0; }
.unit-head p { margin: 0; color: var(--muted); font-size: 15px; }
.note {
  margin: 16px 0 0;
  padding: 12px 16px;
  border-radius: 16px;
  background: var(--k-soft);
  font-weight: 600;
}
.summary { border: 2px solid var(--ok); }

.stepper { display: flex; gap: 8px; margin: 16px 0 0; padding: 4px 2px 10px; overflow-x: auto; scrollbar-width: thin; }
.step {
  display: flex;
  flex: none;
  align-items: center;
  gap: 8px;
  max-width: 250px;
  padding: 7px 14px 7px 7px;
  background: var(--surface);
}
.step-num {
  display: grid;
  flex: none;
  place-items: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--surface-2);
  font-size: 13px;
  font-weight: 800;
}
.step-label { overflow: hidden; font-size: 14px; text-overflow: ellipsis; white-space: nowrap; }
.step-count { color: var(--muted); font-size: 12px; }
.step.complete .step-num { background: var(--ok); color: var(--surface); }
.step.active { border-color: var(--k); box-shadow: 0 0 0 3px var(--k-soft); }
.step.active .step-num { background: var(--k); color: var(--on-k); }

.part-of { color: var(--k); font-size: 12px; font-weight: 800; letter-spacing: .06em; text-transform: uppercase; }
.part h2 { margin-top: 2px; }
.instructions { margin: 0 0 12px; padding: 10px 14px; border-radius: 14px; background: var(--k-soft); font-weight: 600; }
.tr { margin: 6px 0; color: var(--muted); font-size: 15px; }
.flag {
  display: inline-block;
  padding: 1px 6px;
  border-radius: 5px;
  background: #e30a17;
  color: #fff;
  font-size: 11px;
  font-weight: 800;
  letter-spacing: .05em;
}
.passage {
  margin: 16px 0;
  padding: 6px 20px;
  border-left: 4px solid var(--k);
  border-radius: 0 16px 16px 0;
  background: var(--surface-2);
  font-family: var(--serif);
  font-size: 18px;
  line-height: 1.75;
}
.video { position: relative; margin: 14px 0; aspect-ratio: 16 / 9; }
.video iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; border-radius: 14px; }
.player {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  margin: 10px 0;
  padding: 10px 14px;
  border-radius: 16px;
  background: var(--k-soft);
}
.player-icon { font-size: 22px; }
.player button { border-color: var(--k); background: var(--k); color: var(--on-k); }
.player button.restart { background: var(--surface); color: var(--k); }
.links { padding-left: 1.2em; }

.items { margin: 8px 0 0; padding: 0; list-style: none; }
.item { display: flex; gap: 12px; padding: 18px 0; border-top: 1px dashed var(--line); }
.item:first-child { border-top: 0; }
.num {
  display: grid;
  flex: none;
  place-items: center;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--k-soft);
  color: var(--k);
  font-size: 13px;
  font-weight: 800;
}
.item-body { flex: 1; min-width: 0; }
.prompt { margin: 2px 0 10px; }
.options { display: grid; gap: 8px; }
.option {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 10px 14px;
  background: var(--surface);
  border: 1.5px solid var(--line);
  border-radius: 14px;
  cursor: pointer;
  transition: border-color .15s ease, background .15s ease;
}
.option:hover { border-color: var(--k); }
.option:has(input:checked) { border-color: var(--k); background: var(--k-soft); }
.option input { flex: none; margin-top: 5px; accent-color: var(--k); }
.options .option.right { border-color: var(--ok); background: var(--ok-soft); }
.options .option.picked-wrong { border-color: var(--bad); background: var(--bad-soft); }
.actions { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; margin-top: 8px; }
.actions button { padding: 5px 12px; font-size: 14px; }
button.idk.on { border-color: var(--warn); background: var(--warn-soft); color: var(--warn); }
button.check { border-color: var(--k); color: var(--k); }
.status { color: var(--muted); font-size: 13px; }
.status.error { color: var(--bad); }
.counter { margin-top: 4px; font-size: 14px; }
.feedback { margin-top: 10px; padding: 12px 14px; border-radius: 14px; background: var(--surface-2); font-size: 15px; }
.feedback:empty { display: none; }
.feedback[data-result="correct"] { background: var(--ok-soft); }
.feedback[data-result="wrong"] { background: var(--bad-soft); }
.feedback[data-result="partial"] { background: var(--warn-soft); }
.feedback > * + * { margin-top: 6px; }
.feedback p { margin: 0; }
.verdict { font-weight: 800; }
.verdict.correct { color: var(--ok); }
.verdict.wrong { color: var(--bad); }
.verdict.partial, .verdict.wait { color: var(--warn); }
.verdict.none { color: var(--muted); }

.section-nav { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin: 20px 0; }
.done { margin: 0; color: var(--ok); font-weight: 700; text-align: right; }

.savebar {
  position: fixed;
  right: 0;
  bottom: 0;
  left: 0;
  z-index: 4;
  padding: 10px 16px calc(10px + env(safe-area-inset-bottom));
  background: var(--surface);
  border-top: 1px solid var(--line);
  box-shadow: 0 -6px 24px rgba(31, 35, 55, .08);
}
.savebar-inner { display: flex; align-items: center; gap: 14px; max-width: 860px; margin: 0 auto; }
.savebar-progress { display: grid; flex: 1; gap: 6px; min-width: 0; }
.savebar-line { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 2px 12px; font-size: 13px; }
.save-count { font-weight: 700; }
.save-state { color: var(--ok); }
.save-state.error { color: var(--bad); font-weight: 700; }
.savebar-actions { display: flex; flex: none; gap: 8px; }
.savebar-actions button { padding: 8px 14px; font-size: 14px; }

.toast {
  position: fixed;
  bottom: 100px;
  left: 50%;
  z-index: 10;
  max-width: calc(100% - 32px);
  padding: 12px 20px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--bg);
  font-weight: 700;
  box-shadow: var(--shadow);
  transform: translateX(-50%);
  animation: toast-in .25s ease;
  transition: opacity .4s ease;
}
.toast.out { opacity: 0; }
@keyframes toast-in { from { opacity: 0; transform: translate(-50%, 10px); } }

/* ---------- login ---------- */

.login-page {
  min-height: 100vh;
  background:
    radial-gradient(circle at 12% 18%, rgba(124, 77, 255, .22), transparent 42%),
    radial-gradient(circle at 88% 12%, rgba(255, 122, 89, .24), transparent 40%),
    radial-gradient(circle at 50% 100%, rgba(61, 90, 241, .2), transparent 52%),
    var(--bg);
}
main.login {
  display: grid;
  align-content: center;
  justify-items: center;
  gap: 18px;
  max-width: none;
  min-height: 100vh;
  min-height: 100dvh;
  padding: 24px 16px;
}
.login-card {
  width: 100%;
  max-width: 400px;
  padding: 34px 28px 28px;
  background: var(--surface);
  border-radius: 28px;
  box-shadow: 0 24px 64px rgba(31, 35, 55, .16);
  text-align: center;
}
.login-card h1 { margin-bottom: 4px; }
.login-card > p { margin: 0; }
.login-mark {
  display: grid;
  place-items: center;
  width: 66px;
  height: 66px;
  margin: 0 auto 16px;
  border-radius: 21px;
  background: var(--hero);
  color: #fff;
  font-family: var(--serif);
  font-size: 34px;
  font-weight: 700;
}
.login-card form { display: grid; gap: 14px; margin-top: 22px; text-align: left; }
.login-card label { display: grid; gap: 6px; font-size: 14px; font-weight: 700; }
.login-card button { width: 100%; margin-top: 6px; }
.login-card > .login-error {
  margin: 18px 0 0;
  padding: 10px 14px;
  border-radius: 12px;
  background: var(--bad-soft);
  color: var(--bad);
  font-size: 14px;
  font-weight: 700;
}
.login-foot { margin: 0; color: var(--muted); font-size: 14px; }

/* ---------- small screens ---------- */

@media (max-width: 640px) {
  body { font-size: 16px; }
  h1 { font-size: 25px; }
  main { padding-top: 14px; }
  .hero { flex-direction: column; align-items: flex-start; padding: 22px; }
  .hero h1 { font-size: 27px; }
  .goal { display: flex; align-items: center; gap: 12px; }
  .ring { width: 76px; height: 76px; font-size: 17px; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .duo { grid-template-columns: 1fr; }
  .continue { flex-wrap: wrap; }
  .go { width: 100%; text-align: center; }
  .steps small { display: none; }
  .steps strong { font-size: 12px; }
  .box { padding: 16px; }
  .unit-head { padding: 16px; }
  .icon.big { width: 50px; height: 50px; font-size: 25px; }
  .item { gap: 10px; }
  .savebar-inner { gap: 10px; }
  .savebar-actions { gap: 6px; }
  .savebar-actions button { padding: 7px 11px; font-size: 13px; }
  .pill { font-size: 12px; padding: 3px 9px; }
  #brand-name { font-size: 17px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; }
}