/* Memorix -- Design-System der Edu-Lernplattform.
   Konzept: digitales Karteikasten/Leitner-System, mit einer frischen,
   knalligen Farbwelt statt gedeckter/blasser Töne: klares, sattes Grün als
   Markenfarbe, sonniges Orange als Akzent, acht kräftige Fach-Farben auf
   hellem Grund -- energetisch und aufgeräumt statt zurückhaltend. Ersetzt
   Bootstrap vollständig -- kein Vendor-Framework mehr. */

@font-face {
  font-family: 'Bitter';
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url('../fonts/Bitter-Bold.woff2') format('woff2');
}
@font-face {
  font-family: 'IBM Plex Sans';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('../fonts/IBMPlexSans-Regular.woff2') format('woff2');
}
@font-face {
  font-family: 'IBM Plex Sans';
  font-style: normal;
  font-weight: 600;
  font-display: swap;
  src: url('../fonts/IBMPlexSans-SemiBold.woff2') format('woff2');
}
@font-face {
  font-family: 'IBM Plex Mono';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url('../fonts/IBMPlexMono-Medium.woff2') format('woff2');
}

:root {
  --ink: #1C2B22;
  --ink-soft: #5C6B60;
  --paper: #F5FAF6;
  --paper-line: #DCEFE0;
  --card: #FFFFFF;
  --card-edge: #E1F0E4;
  --pine: #279651;
  --pine-ink: #FFFFFF;
  --coral: #FF8A1E;
  --coral-ink: #4A2600;
  --focus-ring: #2D7FF9;
  --danger: #E13B38;
  --amber: #A8720E;
  --sky: #2E6FE0;

  --subj-rot: #E13B38;
  --subj-gruen: #279651;
  --subj-ocker: #A8720E;
  --subj-petrol: #0C8983;
  --subj-violett: #8B5FBF;
  --subj-blau: #2E6FE0;
  --subj-rostbraun: #B85A26;
  --subj-taubenblau: #5C7FB5;
  --subj-ink: #FFFFFF;

  --shadow-card: 0 1px 0 var(--card-edge), 0 6px 14px -8px rgba(28, 43, 34, 0.18);
  --font-display: 'Bitter', Georgia, 'Times New Roman', serif;
  --font-body: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'IBM Plex Mono', ui-monospace, 'SF Mono', Consolas, monospace;

  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #E8F5EC;
    --ink-soft: #9DBBA8;
    --paper: #10241A;
    --paper-line: #1E3A29;
    --card: #16301F;
    --card-edge: #24462F;
    --pine: #4ED67F;
    --pine-ink: #0B2414;
    --coral: #FFA04D;
    --coral-ink: #3D1F00;
    --danger: #FF6B6B;
    --amber: #F0BA55;
    --sky: #5B9CFF;

    --subj-rot: #FF7A77;
    --subj-gruen: #4ED67F;
    --subj-ocker: #F5C363;
    --subj-petrol: #3FCFC7;
    --subj-violett: #B48CE0;
    --subj-blau: #5B9CFF;
    --subj-rostbraun: #F0935C;
    --subj-taubenblau: #8CA9DE;
    --subj-ink: #14210C;

    --shadow-card: 0 1px 0 var(--card-edge), 0 10px 20px -10px rgba(0, 0, 0, 0.6);
    color-scheme: dark;
  }
}

:root[data-theme="dark"] {
  --ink: #E8F5EC;
  --ink-soft: #9DBBA8;
  --paper: #10241A;
  --paper-line: #1E3A29;
  --card: #16301F;
  --card-edge: #24462F;
  --pine: #4ED67F;
  --pine-ink: #0B2414;
  --coral: #FFA04D;
  --coral-ink: #3D1F00;
  --danger: #FF6B6B;
  --amber: #F0BA55;
  --sky: #5B9CFF;
  --subj-rot: #FF7A77;
  --subj-gruen: #4ED67F;
  --subj-ocker: #F5C363;
  --subj-petrol: #3FCFC7;
  --subj-violett: #B48CE0;
  --subj-blau: #5B9CFF;
  --subj-rostbraun: #F0935C;
  --subj-taubenblau: #8CA9DE;
  --subj-ink: #14210C;
  --shadow-card: 0 1px 0 var(--card-edge), 0 10px 20px -10px rgba(0, 0, 0, 0.6);
  color-scheme: dark;
}

:root[data-theme="light"] {
  --ink: #1C2B22;
  --ink-soft: #5C6B60;
  --paper: #F5FAF6;
  --paper-line: #DCEFE0;
  --card: #FFFFFF;
  --card-edge: #E1F0E4;
  --pine: #279651;
  --pine-ink: #FFFFFF;
  --coral: #FF8A1E;
  --coral-ink: #4A2600;
  --danger: #E13B38;
  --amber: #A8720E;
  --sky: #2E6FE0;
  --subj-rot: #E13B38;
  --subj-gruen: #279651;
  --subj-ocker: #A8720E;
  --subj-petrol: #0C8983;
  --subj-violett: #8B5FBF;
  --subj-blau: #2E6FE0;
  --subj-rostbraun: #B85A26;
  --subj-taubenblau: #5C7FB5;
  --subj-ink: #FFFFFF;
  --shadow-card: 0 1px 0 var(--card-edge), 0 6px 14px -8px rgba(28, 43, 34, 0.18);
  color-scheme: light;
}

/* Fach-Farbe: data-subject-color setzt --subject-bg/--subject-fg lokal */
[data-subject-color="rot"]        { --subject-bg: var(--subj-rot);        --subject-fg: var(--subj-ink); }
[data-subject-color="gruen"]      { --subject-bg: var(--subj-gruen);      --subject-fg: var(--subj-ink); }
[data-subject-color="ocker"]      { --subject-bg: var(--subj-ocker);      --subject-fg: var(--subj-ink); }
[data-subject-color="petrol"]     { --subject-bg: var(--subj-petrol);     --subject-fg: var(--subj-ink); }
[data-subject-color="violett"]    { --subject-bg: var(--subj-violett);    --subject-fg: var(--subj-ink); }
[data-subject-color="blau"]       { --subject-bg: var(--subj-blau);       --subject-fg: var(--subj-ink); }
[data-subject-color="rostbraun"]  { --subject-bg: var(--subj-rostbraun);  --subject-fg: var(--subj-ink); }
[data-subject-color="taubenblau"] { --subject-bg: var(--subj-taubenblau); --subject-fg: var(--subj-ink); }

* { box-sizing: border-box; }

html, body { height: 100%; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

h1, h2, h3, h4 { text-wrap: balance; }

.container {
  max-width: 920px;
  margin: 0 auto;
  padding: 0 1rem;
}

@media (min-width: 640px) {
  .container { padding: 0 1.5rem; }
}

/* ---------- Header ---------- */
/* Mobile-first: gestapelt/linksbündig als Basis, ab Tablet-Breite in einer Zeile. */

.site-header {
  border-bottom: 3px solid var(--ink);
  background: var(--paper);
}

.site-header .bar {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.85rem;
  padding: 1rem 0;
}

@media (min-width: 640px) {
  .site-header .bar {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 1.25rem;
    flex-wrap: wrap;
    padding: 1.25rem 0;
  }
}

.brand {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.5rem;
  text-decoration: none;
  letter-spacing: -0.01em;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.streak {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--card);
  border: 1px solid var(--card-edge);
  box-shadow: var(--shadow-card);
  border-radius: 999px;
  padding: 0.4rem 0.85rem 0.4rem 0.55rem;
}

.streak svg { width: 20px; height: 20px; flex: none; }

.streak .num {
  font-family: var(--font-mono);
  font-weight: 500;
  font-variant-numeric: tabular-nums;
  font-size: 1.05rem;
}

.streak .label {
  font-size: 0.72rem;
  color: var(--ink-soft);
  text-transform: uppercase;
  letter-spacing: 0.07em;
}

.username {
  font-size: 0.9rem;
  color: var(--ink-soft);
}

/* ---------- Theme-Umschalter (iOS-Kippschalter) ---------- */
/* Füllfarbe/Knopf-Position folgen standardmäßig der Systemeinstellung
   (prefers-color-scheme), ein per JS gesetztes data-theme auf <html>
   überschreibt es in beide Richtungen -- gleiches Muster wie die
   Farb-Tokens weiter oben. aria-checked wird nur für Screenreader von
   theme.js mitgeführt, steuert aber nicht die Optik (kein Flackern beim
   ersten Rendern, bevor JS läuft). */

.theme-switch {
  /* Ohne appearance: none übernimmt Safari die native Button-Optik (graue
     Kapsel) und ignoriert dabei unser Flex-Layout für die Icon/Track-Kinder. */
  -webkit-appearance: none;
  appearance: none;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background: transparent;
  border: none;
  padding: 0.4rem 0.1rem;
  min-height: 44px;
  cursor: pointer;
}

.theme-switch-icon { width: 16px; height: 16px; flex: none; color: var(--ink-soft); }

.theme-switch-track {
  position: relative;
  width: 46px;
  height: 26px;
  border-radius: 999px;
  background: var(--card-edge);
  border: 1px solid var(--paper-line);
  flex: none;
  transition: background-color 200ms ease;
}

.theme-switch-knob {
  position: absolute;
  top: 1px;
  left: 1px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #FFFFFF;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
  transition: transform 200ms ease;
}

@media (prefers-reduced-motion: reduce) {
  .theme-switch-track, .theme-switch-knob { transition: none; }
}

@media (prefers-color-scheme: dark) {
  .theme-switch-track { background: var(--pine); }
  .theme-switch-knob { transform: translateX(20px); }
}

:root[data-theme="dark"] .theme-switch-track { background: var(--pine); }
:root[data-theme="dark"] .theme-switch-knob { transform: translateX(20px); }
:root[data-theme="light"] .theme-switch-track { background: var(--card-edge); }
:root[data-theme="light"] .theme-switch-knob { transform: translateX(0); }

/* ---------- Buttons ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 0.88rem;
  line-height: 1;
  border-radius: 10px;
  /* min-height 44px -- Apples Empfehlung für Touch-Ziele */
  min-height: 44px;
  padding: 0.65rem 1.1rem;
  border: 2px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: transform 120ms ease, filter 120ms ease;
}

.btn:hover { transform: translateY(-1px); }

.btn-primary { background: var(--pine); color: var(--pine-ink); }
.btn-accent  { background: var(--coral); color: var(--coral-ink); }
.btn-ghost   { background: transparent; color: var(--ink); border-color: var(--card-edge); }
.btn-ghost:hover { border-color: var(--ink-soft); }
.btn-sm { padding: 0.45rem 0.8rem; font-size: 0.8rem; }

button.btn { font: inherit; font-family: var(--font-body); font-weight: 600; }

/* ---------- Forms ---------- */

.field { margin-bottom: 1rem; }

.field label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 0.3rem;
}

.input, .select, textarea.input {
  width: 100%;
  font-family: var(--font-body);
  /* 16px, nicht kleiner -- sonst zoomt mobile Safari beim Fokussieren hinein */
  font-size: 1rem;
  color: var(--ink);
  background: var(--card);
  border: 1px solid var(--card-edge);
  border-radius: 8px;
  padding: 0.65rem 0.75rem;
  min-height: 44px;
}

.input:focus, .select:focus, textarea.input:focus {
  outline: 3px solid var(--focus-ring);
  outline-offset: 1px;
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
}

.checkbox-list {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.checkbox-list label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 400;
}

.alert {
  border-radius: 10px;
  padding: 0.75rem 1rem;
  margin-bottom: 1rem;
  font-size: 0.9rem;
}

.alert-info { background: var(--card); border: 1px solid var(--card-edge); }
.alert-danger { background: var(--card); border: 1px solid var(--danger); color: var(--danger); }

:focus-visible {
  outline: 3px solid var(--focus-ring);
  outline-offset: 2px;
}

/* ---------- Panel / card container ---------- */

.panel {
  background: var(--card);
  border: 1px solid var(--card-edge);
  border-radius: 14px;
  box-shadow: var(--shadow-card);
  padding: 1.75rem;
}

/* ---------- Filterleiste (deck_list) ---------- */
/* Mobile-first: Felder untereinander, ab Tablet-Breite in einer Zeile. */

.filter-bar {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  padding: 1rem;
  margin-bottom: 1.5rem;
  background: var(--card);
  border: 1px solid var(--card-edge);
  border-radius: 12px;
  box-shadow: var(--shadow-card);
}

.filter-bar .field { margin-bottom: 0; flex: 1; }

.filter-actions { display: flex; gap: 0.5rem; align-items: center; }

@media (min-width: 640px) {
  .filter-bar {
    flex-direction: row;
    align-items: flex-end;
  }
  .filter-actions { margin-left: auto; }
}

/* ---------- Klassenstufe / Fach / Deck (deck_list) ---------- */

.grade {
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
  margin: 0 0 1.1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px dashed var(--paper-line);
}

.grade:not(:first-child) { margin-top: 2.25rem; }

.grade h2 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.5rem;
  margin: 0;
}

.grade .count {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--ink-soft);
}

.subject-group { margin-bottom: 1.4rem; }
.subject-group:last-child { margin-bottom: 0; }

.subject-tab {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--subject-fg, var(--ink));
  background: var(--subject-bg, var(--card-edge));
  border-radius: 7px 7px 0 0;
  padding: 0.35rem 0.75rem;
  margin-bottom: -1px;
}

.subject-tab .dot { width: 8px; height: 8px; border-radius: 50%; background: currentColor; }

/* Mobile-first: eine breite Kachel pro Zeile auf dem Handy, ab Tablet-Breite
   nebeneinander in einem gleichmäßigen Raster (keine variable Spaltenzahl per
   auto-fill -- so bleiben die Kacheln bewusst groß statt sich zu verkleinern). */
.deck-row {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.1rem;
  border-top: 1px solid var(--subject-bg, var(--card-edge));
  padding-top: 1.1rem;
  border-radius: 0 10px 10px 10px;
}

@media (min-width: 640px) {
  .deck-row { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 960px) {
  .deck-row { grid-template-columns: repeat(3, 1fr); }
}

.deck { position: relative; text-decoration: none; color: inherit; padding-top: 10px; display: block; }

.deck .stack-shadow-2, .deck .stack-shadow-1 {
  position: absolute;
  top: 10px; left: 7px; right: -7px; bottom: -7px;
  background: var(--card-edge);
  border: 1px solid var(--card-edge);
  border-radius: 14px;
}
.deck .stack-shadow-1 { top: 5px; left: 4px; right: -4px; bottom: -4px; }

.deck .face {
  position: relative;
  background: var(--card);
  border: 1px solid var(--card-edge);
  border-top: 6px solid var(--subject-bg, var(--pine));
  border-radius: 14px;
  padding: 1.35rem 1.4rem 1.5rem;
  min-height: 148px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: var(--shadow-card);
  transition: transform 140ms ease;
}

.deck:hover .face, .deck:has(:focus-visible) .face { transform: translateY(-4px); }

/* Kachel-Klick geht direkt ins Lernen (voll deckender, unsichtbarer Link);
   der Stift-Button liegt als eigener fokussierbarer Link darüber (höherer
   z-index), damit sein Klickbereich Vorrang vor dem Lern-Link hat. */
.deck-link {
  position: absolute;
  inset: 0;
  z-index: 1;
  border-radius: 14px;
}

.deck-edit {
  position: absolute;
  z-index: 2;
  top: 0.6rem;
  right: 0.6rem;
  width: 40px;
  height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--card);
  border: 1px solid var(--card-edge);
  color: var(--ink-soft);
  box-shadow: var(--shadow-card);
  transition: color 120ms ease, border-color 120ms ease;
}

.deck-edit:hover { color: var(--ink); border-color: var(--ink-soft); }
.deck-edit svg { width: 17px; height: 17px; }

.deck .topic {
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--ink-soft);
  margin: 0 0 0.3rem;
}

.deck h3 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.3rem;
  margin: 0 0 0.9rem;
}

.deck .meta { display: flex; align-items: center; justify-content: space-between; }

.deck .progress-track {
  flex: 1;
  height: 8px;
  border-radius: 4px;
  background: var(--paper-line);
  margin-right: 0.75rem;
  overflow: hidden;
}

.deck .progress-fill { height: 100%; background: var(--pine); border-radius: 4px; }

.due-badge {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 500;
  font-variant-numeric: tabular-nums;
  background: var(--coral);
  color: var(--coral-ink);
  border-radius: 999px;
  padding: 0.25rem 0.7rem;
  white-space: nowrap;
}

.due-badge.zero { background: var(--paper-line); color: var(--ink-soft); }

.shared-tag { font-size: 0.68rem; color: var(--ink-soft); margin-top: 0.4rem; display: block; }

/* ---------- Deck detail ---------- */

.detail-head {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

@media (min-width: 640px) {
  .detail-head {
    flex-direction: row;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
  }
}

.detail-head .actions { display: flex; gap: 0.5rem; flex-wrap: wrap; }

.detail-head h1 { font-family: var(--font-display); font-size: 1.6rem; margin: 0; }

.breadcrumb-meta { font-family: var(--font-mono); font-size: 0.78rem; color: var(--ink-soft); margin: 0.3rem 0 0; }

.card-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--card-edge);
}
.card-row:last-child { border-bottom: none; }
.card-row .back-text { color: var(--ink-soft); font-size: 0.85rem; margin-top: 0.15rem; }

/* ---------- Study session ---------- */

.session {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.25rem;
  padding: 0.5rem 0;
}

.breadcrumb { font-family: var(--font-mono); font-size: 0.8rem; color: var(--ink-soft); text-align: center; }
.breadcrumb strong { color: var(--ink); font-weight: 500; }

.due-remaining {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--ink-soft);
}
.due-remaining .num { font-weight: 500; color: var(--ink); }

.flip-scene { width: min(420px, 100%); aspect-ratio: 5 / 3; perspective: 1400px; }

.flip-card {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 480ms cubic-bezier(0.2, 0.7, 0.3, 1);
  transform-style: preserve-3d;
  cursor: pointer;
  border-radius: 16px;
}

.flip-scene.is-flipped .flip-card { transform: rotateY(180deg); }

@media (prefers-reduced-motion: reduce) {
  .flip-card { transition: none; }
}

.flip-face {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  text-align: center;
  padding: 1.5rem;
  border-radius: 16px;
  background: var(--card);
  border: 1px solid var(--card-edge);
  box-shadow: var(--shadow-card);
  backface-visibility: hidden;
}

.flip-face.back { transform: rotateY(180deg); }
.flip-face img { max-height: 45%; max-width: 100%; border-radius: 8px; object-fit: contain; }

.flip-face .kicker {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink-soft);
}

.flip-face .word { font-family: var(--font-display); font-weight: 700; font-size: clamp(1.4rem, 5vw, 2rem); }

.flip-hint { font-size: 0.82rem; color: var(--ink-soft); }

.ratings {
  display: grid;
  /* Mobile: 2x2 -- größere Tippflächen. Ab 480px passt eine Reihe bequem. */
  grid-template-columns: repeat(2, 1fr);
  gap: 0.6rem;
  width: 100%;
  max-width: 460px;
  transition: opacity 160ms ease;
}

@media (min-width: 480px) {
  .ratings { grid-template-columns: repeat(4, 1fr); }
}

.ratings[hidden] { display: none; }

.stamp {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  padding: 0.65rem 0.3rem;
  min-height: 44px;
  border-radius: 9px;
  border: 2px solid currentColor;
  background: transparent;
  cursor: pointer;
  transform: rotate(var(--tilt, 0deg));
  transition: transform 120ms ease;
}

.stamp:hover { transform: rotate(0deg) scale(1.04); }

.stamp.again { color: var(--danger); --tilt: -1.5deg; }
.stamp.hard  { color: var(--amber); --tilt: 1deg; }
.stamp.good  { color: var(--pine); --tilt: -1deg; }
.stamp.easy  { color: var(--sky); --tilt: 1.5deg; }

.session-empty { text-align: center; color: var(--ink-soft); }

.note { max-width: 460px; text-align: center; font-size: 0.85rem; color: var(--ink-soft); }

/* ---------- Login ---------- */

.auth-wrap { display: flex; justify-content: center; padding: 1.25rem 0; }
.auth-panel { width: min(360px, 100%); }
.auth-panel h1 { font-family: var(--font-display); font-size: 1.4rem; margin: 0 0 1rem; }