/* App-specific styles on top of Pico.css.
   Theme variables reuse Pico's own selectors so they win over its defaults. */
:root:not([data-theme=dark]),
[data-theme=light] {
  --pico-primary: #4f46e5;
  --pico-primary-background: #4f46e5;
  --pico-primary-border: #4f46e5;
  --pico-primary-underline: rgba(79, 70, 229, .45);
  --pico-primary-hover: #4338ca;
  --pico-primary-hover-background: #4338ca;
  --pico-primary-hover-border: #4338ca;
  --pico-primary-hover-underline: #4338ca;
  --pico-primary-focus: rgba(79, 70, 229, .25);
  --pico-primary-inverse: #fff;
  --pico-background-color: #f6f7fb;
  --pico-card-background-color: #fff;
  --pico-card-sectioning-background-color: #fafbff;
  --surface-muted: #eef0f8;
  --accent-soft: #eef2ff;
  --success-soft: #e7f7ee;
  --success-ink: #13795b;
  --warn-soft: #fff4e0;
  --warn-ink: #9a5b00;
  --danger-soft: #fdecec;
  --danger-ink: #b42318;
}
@media only screen and (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --pico-primary: #818cf8;
    --pico-primary-background: #6366f1;
    --pico-primary-border: #6366f1;
    --pico-primary-underline: rgba(129, 140, 248, .5);
    --pico-primary-hover: #a5b4fc;
    --pico-primary-hover-background: #4f46e5;
    --pico-primary-hover-border: #4f46e5;
    --pico-primary-focus: rgba(129, 140, 248, .3);
    --pico-primary-inverse: #fff;
    --pico-background-color: #0f1117;
    --pico-card-background-color: #171a23;
    --surface-muted: #1f2330;
    --accent-soft: #23264a;
    --success-soft: #11291f;
    --success-ink: #5dd39e;
    --warn-soft: #2e2410;
    --warn-ink: #f5b950;
    --danger-soft: #2f1517;
    --danger-ink: #ff8a80;
  }
}
[data-theme=dark] {
  --pico-primary: #818cf8;
  --pico-primary-background: #6366f1;
  --pico-primary-border: #6366f1;
  --pico-primary-underline: rgba(129, 140, 248, .5);
  --pico-primary-hover: #a5b4fc;
  --pico-primary-hover-background: #4f46e5;
  --pico-primary-hover-border: #4f46e5;
  --pico-primary-focus: rgba(129, 140, 248, .3);
  --pico-primary-inverse: #fff;
  --pico-background-color: #0f1117;
  --pico-card-background-color: #171a23;
  --surface-muted: #1f2330;
  --accent-soft: #23264a;
  --success-soft: #11291f;
  --success-ink: #5dd39e;
  --warn-soft: #2e2410;
  --warn-ink: #f5b950;
  --danger-soft: #2f1517;
  --danger-ink: #ff8a80;
}
:root {
  --pico-font-family: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --pico-border-radius: .6rem;
  --pico-card-box-shadow: 0 1px 2px rgba(16, 24, 40, .05), 0 4px 16px rgba(16, 24, 40, .06);
  --pico-typography-spacing-vertical: .9rem;
}

/* ---- Layout ---------------------------------------------------------------- */
body { min-height: 100vh; display: flex; flex-direction: column; }
body > main { flex: 1; padding-top: 1.5rem; }
body > footer { padding: 1.5rem 0; }

.site-header {
  position: sticky; top: 0; z-index: 20;
  background: color-mix(in srgb, var(--pico-background-color) 85%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--pico-muted-border-color);
}
.site-header nav { padding: .25rem 0; }
.site-header nav ul { margin: 0; }
.site-header nav li { padding-top: .5rem; padding-bottom: .5rem; }
.brand { display: inline-flex; align-items: center; gap: .5rem; font-weight: 800; color: var(--pico-color); text-decoration: none; letter-spacing: -.01em; }
.brand-mark { width: 1.75rem; height: 1.75rem; border-radius: .5rem; display: grid; place-items: center; background: linear-gradient(135deg, #6366f1, #8b5cf6); color: #fff; font-size: .9rem; }
.nav-links a { padding: .35rem .65rem; border-radius: .5rem; text-decoration: none; color: var(--pico-muted-color); }
.nav-links a:hover { color: var(--pico-color); background: var(--surface-muted); }
.nav-links a[aria-current="page"] { color: var(--pico-primary); background: var(--accent-soft); font-weight: 600; }
.nav-user { display: inline-flex; align-items: center; gap: .5rem; }
.avatar { width: 2rem; height: 2rem; border-radius: 50%; display: grid; place-items: center; background: var(--accent-soft); color: var(--pico-primary); font-weight: 700; font-size: .85rem; text-transform: uppercase; }
.icon-btn { padding: .35rem .5rem; margin: 0; line-height: 1; }
.icon { width: 1em; height: 1em; vertical-align: -0.15em; margin-right: .3em; }
.icon-btn .icon { margin: 0; vertical-align: 0; }

@media (max-width: 860px) {
  .site-header nav { flex-wrap: wrap; }
  .site-header nav > ul.nav-links { order: 3; width: 100%; overflow-x: auto; scrollbar-width: none; margin: 0 calc(var(--pico-nav-element-spacing-horizontal) * -1); }
  .site-header nav > ul.nav-links li { padding-top: 0; }
  .nav-user .who { display: none; }
}

.page-head { display: flex; flex-wrap: wrap; gap: .75rem 1rem; align-items: center; justify-content: space-between; margin-bottom: 1.25rem; }
.page-head h1 { margin: 0; }
.page-head p { margin: .25rem 0 0; }
.breadcrumb { font-size: .9rem; margin-bottom: .5rem; }
.breadcrumb a { text-decoration: none; }
.section-title { display: flex; align-items: baseline; gap: .5rem; margin: 2rem 0 .75rem; font-size: 1.15rem; }
.section-title .count { color: var(--pico-muted-color); font-weight: 500; }

/* ---- Components ------------------------------------------------------------ */
.card { border: 1px solid var(--pico-muted-border-color); border-radius: var(--pico-border-radius); padding: 1.25rem; margin: 0 0 1rem; background: var(--pico-card-background-color); box-shadow: var(--pico-card-box-shadow); }
.card > :last-child { margin-bottom: 0; }
.card h2, .card h3 { margin-bottom: .5rem; }

.grid-cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 1rem; }
.grid-cards > .card { margin: 0; display: flex; flex-direction: column; }
.deck-card h3 { font-size: 1.15rem; margin: .25rem 0 .35rem; }
.deck-card h3 a { text-decoration: none; color: var(--pico-color); }
.deck-card h3 a:hover { color: var(--pico-primary); }
.deck-card .desc { color: var(--pico-muted-color); font-size: .95rem; flex: 1; margin-bottom: .75rem; display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.deck-card .meta { display: flex; flex-wrap: wrap; gap: .35rem; margin-bottom: .9rem; }
.deck-card .stats { display: flex; gap: 1.25rem; font-size: .9rem; color: var(--pico-muted-color); margin-bottom: 1rem; }
.deck-card .stats strong { color: var(--pico-color); font-size: 1.1rem; display: block; line-height: 1.1; }
.deck-card .stats .due strong { color: var(--pico-primary); }

.actions { display: flex; flex-wrap: wrap; gap: .5rem; align-items: center; }
.actions form { margin: 0; }
.actions > *, .actions button, .actions [role=button] { width: auto; margin: 0; }
.push { margin-left: auto; }
button, [role=button], input[type=submit] { width: auto; }
form > button[type=submit], form > [type=submit] { margin-top: .25rem; }
.sm { padding: .3rem .7rem; font-size: .875rem; }
button.danger, .danger[role=button] { background: var(--pico-del-color); border-color: var(--pico-del-color); color: #fff; }
button.danger.outline { background: transparent; color: var(--danger-ink); border-color: currentColor; }
button.link { background: none; border: none; padding: 0; color: var(--pico-primary); text-decoration: underline; }

.badge { display: inline-flex; align-items: center; gap: .3rem; padding: .1rem .55rem; border-radius: 999px; font-size: .75rem; font-weight: 600; line-height: 1.6; background: var(--surface-muted); color: var(--pico-muted-color); white-space: nowrap; }
.badge.accent { background: var(--accent-soft); color: var(--pico-primary); }
.badge.success { background: var(--success-soft); color: var(--success-ink); }
.badge.warn { background: var(--warn-soft); color: var(--warn-ink); }
.badge.danger { background: var(--danger-soft); color: var(--danger-ink); }
.tag { display: inline-block; padding: .05rem .5rem; border-radius: 999px; margin: 0 .3rem .3rem 0; font-size: .8rem; background: var(--surface-muted); color: var(--pico-muted-color); }

.empty { text-align: center; padding: 2.5rem 1rem; border: 2px dashed var(--pico-muted-border-color); border-radius: var(--pico-border-radius); color: var(--pico-muted-color); }
.empty h2, .empty h3 { color: var(--pico-color); margin-bottom: .35rem; }
.empty .actions { justify-content: center; margin-top: 1rem; }

.callout { border-radius: var(--pico-border-radius); padding: .75rem 1rem; margin-bottom: 1rem; background: var(--accent-soft); }
.callout.warn { background: var(--warn-soft); color: var(--warn-ink); }
.callout.danger { background: var(--danger-soft); color: var(--danger-ink); }
.callout.success { background: var(--success-soft); color: var(--success-ink); }

.toast { position: fixed; top: 5.5rem; right: 1rem; z-index: 30; max-width: min(28rem, calc(100vw - 2rem)); padding: .7rem 1rem; border-radius: var(--pico-border-radius); background: var(--success-soft); color: var(--success-ink); border: 1px solid currentColor; box-shadow: var(--pico-card-box-shadow); animation: toast 5s ease forwards; }
@keyframes toast { 0%, 85% { opacity: 1; transform: none; } 100% { opacity: 0; transform: translateY(-.5rem); visibility: hidden; } }

.stat-tiles { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 1rem; margin-bottom: 1.5rem; }
.stat-tiles .card { margin: 0; padding: 1rem; }
.stat-tiles strong { display: block; font-size: 1.6rem; line-height: 1.1; }
.stat-tiles span { color: var(--pico-muted-color); font-size: .85rem; }
.stat-tiles .warn strong { color: var(--warn-ink); }

.table-wrap { overflow-x: auto; border: 1px solid var(--pico-muted-border-color); border-radius: var(--pico-border-radius); background: var(--pico-card-background-color); margin-bottom: 1rem; }
.table-wrap table { margin: 0; }
.table-wrap th, .table-wrap td { padding: .65rem .9rem; vertical-align: middle; }
.table-wrap td form { margin: 0; }
.nowrap { white-space: nowrap; }

fieldset.panel { border: 1px solid var(--pico-muted-border-color); border-radius: var(--pico-border-radius); padding: 1rem 1.25rem .25rem; margin-bottom: 1rem; background: var(--pico-card-background-color); }
fieldset.panel legend { font-weight: 700; padding: 0 .4rem; margin-left: -.4rem; }
.hint { display: block; color: var(--pico-muted-color); font-size: .85rem; margin: -.4rem 0 .9rem; }
label > .hint { margin: .15rem 0 0 2.6rem; }
.grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 0 1rem; }

details.disclosure { border: 1px solid var(--pico-muted-border-color); border-radius: var(--pico-border-radius); padding: .75rem 1rem; background: var(--pico-card-background-color); margin-bottom: 1rem; }
details.disclosure > summary { font-weight: 600; }
details.disclosure[open] > summary { margin-bottom: 1rem; }

.qa-list { display: grid; gap: .6rem; }
.qa { border: 1px solid var(--pico-muted-border-color); border-radius: var(--pico-border-radius); background: var(--pico-card-background-color); padding: .7rem 1rem; margin: 0; }
.qa > summary { font-weight: 600; list-style: none; display: flex; gap: .75rem; align-items: center; }
.qa > summary::-webkit-details-marker { display: none; }
.qa > summary::after { margin-left: auto; }
.qa > summary .q { flex: 1; }
.qa[open] > summary { margin-bottom: .75rem; }
.qa dl { margin: 0 0 .75rem; display: grid; grid-template-columns: max-content 1fr; gap: .35rem 1rem; }
.qa dt { color: var(--pico-muted-color); font-size: .85rem; }
.qa dd { margin: 0; }

.danger-zone { border-color: color-mix(in srgb, var(--pico-del-color) 45%, transparent); }
.danger-zone h3 { color: var(--danger-ink); }

dialog article { max-width: 640px; width: 100%; }
dialog article > header { display: flex; align-items: center; justify-content: space-between; }
dialog article > header h2 { margin: 0; font-size: 1.2rem; }
dialog article > header button { margin: 0; }

.auth-wrap { max-width: 420px; margin: 2rem auto; }
.auth-wrap .brand { font-size: 1.4rem; justify-content: center; display: flex; margin-bottom: 1.25rem; }
.auth-wrap .card { padding: 1.75rem; }
.auth-wrap h1 { font-size: 1.5rem; text-align: center; margin-bottom: 1.25rem; }
.auth-wrap form button { width: 100%; }
.auth-wrap .alt { text-align: center; margin-top: 1rem; font-size: .95rem; }

.search { max-width: 22rem; margin: 0; }
.token-reveal { display: flex; gap: .5rem; align-items: stretch; }
.token-reveal code { flex: 1; padding: .6rem .8rem; overflow-x: auto; white-space: nowrap; margin: 0; }
.token-reveal button { margin: 0; }
kbd { font-size: .75rem; padding: .1rem .35rem; }
.muted { color: var(--pico-muted-color); }
.error { color: var(--danger-ink); }
.success { color: var(--success-ink); }
.pre { white-space: pre-wrap; overflow-wrap: anywhere; }
[hidden] { display: none !important; }

/* ---- Study ----------------------------------------------------------------- */
.study-toolbar { display: flex; flex-wrap: wrap; gap: .75rem; align-items: center; margin-bottom: 1.25rem; }
.study-toolbar select { width: auto; min-width: 14rem; margin: 0; }
.due-pill { padding: .35rem .8rem; border-radius: 999px; background: var(--accent-soft); color: var(--pico-primary); font-weight: 600; font-size: .9rem; }
.flip { display: grid; perspective: 1400px; max-width: 760px; margin: 0 auto; }
.flip > section { grid-area: 1 / 1; backface-visibility: hidden; transition: transform .55s cubic-bezier(.4, .1, .2, 1); }
#result { transform: rotateY(180deg); }
.flip.flipped #study-card { transform: rotateY(-180deg); }
.flip.flipped #result { transform: rotateY(0deg); }
#study-card, #result { padding: 1.75rem; }
#question { font-size: clamp(1.35rem, 3vw, 1.9rem); margin: .5rem 0 1.25rem; }
.question-row { display: flex; align-items: flex-start; gap: .5rem; }
.question-row #question { flex: 1; }
.question-row button { margin: .5rem 0 0; flex-shrink: 0; }
#card-state { margin: 0; }
.study-actions { display: flex; flex-wrap: wrap; gap: .5rem; align-items: center; }
.study-actions button { margin: 0; }
.study-actions #submit { margin-left: auto; }
#feedback { font-size: 1.05rem; }
.answer-box { padding: .75rem 1rem; border-radius: var(--pico-border-radius); background: var(--success-soft); color: var(--success-ink); font-weight: 600; }
#result h3 { font-size: .8rem; text-transform: uppercase; letter-spacing: .06em; color: var(--pico-muted-color); margin: 1.25rem 0 .4rem; }
#teacher-wrap { border-top: 1px solid var(--pico-muted-border-color); margin-top: 1.25rem; }
#final-rating { font-weight: 600; }
.shortcuts { text-align: center; font-size: .8rem; margin-top: 1rem; }
.empty-study { max-width: 760px; margin: 0 auto; }

#status { position: fixed; bottom: 1rem; left: 50%; transform: translateX(-50%); z-index: 10; padding: .5rem 1rem; border-radius: var(--pico-border-radius); background: var(--pico-card-background-color); border: 1px solid var(--pico-muted-border-color); box-shadow: var(--pico-card-box-shadow); max-width: 90vw; font-size: .9rem; }
#status.error { border-color: var(--pico-del-color); color: var(--danger-ink); }
#status:empty { display: none; }

#eq { width: 96px; height: 28px; }
.recording #record { background: var(--pico-del-color); border-color: var(--pico-del-color); color: #fff; }
.recording #record::before { content: "● "; }

@media (max-width: 600px) {
  .study-actions button { flex: 1 1 100%; }
  .study-actions #submit { margin-left: 0; }
  #study-card, #result { padding: 1.25rem; }
  .page-head .actions { width: 100%; }
}

/* ---- Refinements ------------------------------------------------------------ */
.nav-links a { display: inline-flex; align-items: center; white-space: nowrap; }
form:not(.actions) > button[type=submit] { width: auto; min-width: 10rem; }
.auth-wrap form > button[type=submit] { width: 100%; }
fieldset[role=group] button { white-space: nowrap; }
.deck-card .stats strong { display: inline; margin-right: .25rem; }
@media (max-width: 600px) {
  .shortcuts { display: none; }
  form:not(.actions) > button[type=submit] { width: 100%; }
  table.stack thead { display: none; }
  table.stack, table.stack tbody, table.stack tr, table.stack td { display: block; width: 100%; }
  table.stack tr { padding: .75rem .9rem; border-bottom: 1px solid var(--pico-muted-border-color); }
  table.stack td { padding: .2rem 0; border: none; }
  table.stack td[data-label]::before { content: attr(data-label); display: inline-block; min-width: 6.5rem; color: var(--pico-muted-color); font-size: .8rem; }
  table.stack td:first-child::before { display: none; }
  table.stack td .actions { margin-top: .4rem; }
}