/* ── Reset & Variables ───────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --sidebar-w: 230px;
  --color-bg:        #f0fff4;
  --color-sidebar:   #1b4332;
  --color-sidebar-h: #2d6a4f;
  --color-accent:    #40916c;
  --color-accent2:   #52b788;
  --color-text:      #1a1a2e;
  --color-muted:     #555;
  --color-cell-vowel:  #52b788;
  --color-cell-cons:   #2d6a4f;
  --color-cell-clust:  #1b4332;
  --color-cell-header: #d8f3dc;
  --color-challenge:   #c0392b;
  --color-num-btn:     #1a3c8f;
  --cell-size: 68px;
  --cell-font: 0.85rem;
  --cell-gap:  3px;
  --radius:    6px;
}

body {
  display: flex;
  height: 100vh;
  overflow: hidden;
  font-family: 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
}

/* ── Sidebar ─────────────────────────────────────────────────────────────── */
#sidebar {
  width: var(--sidebar-w);
  min-width: var(--sidebar-w);
  background: var(--color-sidebar);
  color: #fff;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  overflow-x: hidden;
  transition: width 0.25s ease, min-width 0.25s ease;
}

body.sidebar-collapsed #sidebar {
  width: 36px;
  min-width: 36px;
}
body.sidebar-collapsed #nav-logo,
body.sidebar-collapsed #nav-sections,
body.sidebar-collapsed #nav-challenge-btn,
body.sidebar-collapsed #nav-bottom {
  display: none;
}

#sidebar-toggle {
  align-self: flex-end;
  background: none;
  border: none;
  color: rgba(255,255,255,0.7);
  font-size: 1rem;
  cursor: pointer;
  padding: 10px 10px;
  line-height: 1;
  flex-shrink: 0;
}
#sidebar-toggle:hover { color: #fff; }
body.sidebar-collapsed #sidebar-toggle { align-self: center; }

#nav-logo {
  padding: 20px 16px 14px;
  border-bottom: 1px solid rgba(255,255,255,0.15);
  display: flex;
  flex-direction: column;
}
.logo-jp {
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  white-space: nowrap;
  color: #b7e4c7;
}
.logo-en {
  font-size: 0.75rem;
  color: rgba(255,255,255,0.6);
  letter-spacing: 0.08em;
}

#nav-sections {
  flex: 1;
  padding: 8px 0;
  overflow-y: auto;
}

.nav-group {
  margin-bottom: 4px;
}
.posts-list {
  flex: 1;
  overflow-y: auto;
  padding: 24px 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  align-content: flex-start;
}
.post-card {
  background: #fff;
  border: 1px solid #d8f3dc;
  border-radius: var(--radius);
  box-shadow: 0 2px 6px rgba(0,0,0,0.06);
  cursor: pointer;
  overflow: hidden;
  max-width: 360px;
  transition: box-shadow 0.15s, transform 0.15s;
}
.post-card:hover { box-shadow: 0 4px 14px rgba(0,0,0,0.12); transform: translateY(-2px); }
.post-card img { width: 100%; height: auto; display: block; }
.post-card-title {
  padding: 10px 14px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-sidebar);
}
.nav-group-label {
  font-size: 0.65rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.45);
  padding: 8px 16px 4px;
}
.nav-section-btn {
  display: block;
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  color: rgba(255,255,255,0.85);
  padding: 6px 16px 6px 24px;
  font-size: 0.8rem;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
  line-height: 1.4;
}
.nav-section-btn:hover,
.nav-section-btn.active {
  background: rgba(255,255,255,0.12);
  color: #fff;
}

.challenge-nav-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 14px 16px;
  border: none;
  border-top: 1px solid rgba(255,255,255,0.15);
  background: rgba(192,57,43,0.85);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
  text-align: left;
}
.challenge-nav-btn:hover { background: var(--color-challenge); }
.challenge-icon { font-size: 1.1rem; }

/* ── Bottom nav links ────────────────────────────────────────────────────── */
#nav-bottom {
  margin-top: auto;
  border-top: 1px solid rgba(255,255,255,0.15);
  display: flex;
  flex-direction: column;
}

.nav-bottom-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 13px 16px;
  color: rgba(255,255,255,0.85);
  font-size: 0.8rem;
  font-weight: 600;
  text-decoration: none;
  border-top: 1px solid rgba(255,255,255,0.08);
  transition: background 0.15s, color 0.15s;
}
.nav-bottom-btn:first-child { border-top: none; }
.nav-bottom-btn:hover {
  background: var(--color-sidebar-h);
  color: #fff;
}

/* ── Main ────────────────────────────────────────────────────────────────── */
#main {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
}

.view { display: none; flex-direction: column; flex: 1; }
.view.active { display: flex; }

/* ── Post view ───────────────────────────────────────────────────────────── */
.post-header {
  padding: 16px 20px 8px;
  background: #fff;
  border-bottom: 2px solid #d8f3dc;
  flex-shrink: 0;
}
.post-header h2 {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--color-sidebar);
  margin-top: 4px;
}
.post-content {
  flex: 1;
  overflow-y: auto;
  padding: 24px 20px;
}
.post-content img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius);
  box-shadow: 0 2px 10px rgba(0,0,0,0.1);
  display: block;
}

/* ── Home view ───────────────────────────────────────────────────────────── */
.home-header {
  display: flex;
  align-items: center;
  gap: 16px;
}
.home-logo {
  height: 65px;
  width: auto;
  flex-shrink: 0;
  object-fit: contain;
}
.home-header-text {
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.home-hero {
  padding: 3rem 2.5rem;
  max-width: 700px;
}
.home-hero h1 {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--color-sidebar);
  margin-bottom: 2px;
  white-space: nowrap;
}
.home-hero h1 em {
  font-style: normal;
  color: var(--color-accent);
  font-size: 1.25rem;
  margin-left: 6px;
}
.home-subtitle {
  color: var(--color-accent);
  font-size: 1rem;
  margin-bottom: 0;
  font-weight: 500;
}
.home-desc {
  color: var(--color-muted);
  line-height: 1.7;
  margin-bottom: 2rem;
}
.home-cards {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}
.home-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 20px;
  min-width: 160px;
  flex: 1;
  border: 1px solid #d8f3dc;
  box-shadow: 0 2px 6px rgba(0,0,0,0.06);
}
.home-card-icon { font-size: 1.8rem; margin-bottom: 8px; }
.home-card-title { font-weight: 600; font-size: 0.9rem; margin-bottom: 6px; color: var(--color-sidebar); }
.home-card-desc { font-size: 0.8rem; color: var(--color-muted); line-height: 1.5; }

/* ── Practice view ───────────────────────────────────────────────────────── */
#practice-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px 8px;
  background: #fff;
  border-bottom: 2px solid #d8f3dc;
  flex-shrink: 0;
}
#practice-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--color-sidebar);
}
#practice-nav {
  display: flex;
  align-items: center;
  gap: 10px;
}
#practice-progress {
  font-size: 0.75rem;
  color: var(--color-muted);
  min-width: 50px;
  text-align: center;
}
.nav-arrow-btn {
  background: var(--color-accent2);
  border: none;
  color: #fff;
  width: 30px;
  height: 30px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: background 0.15s;
}
.nav-arrow-btn:hover:not(:disabled) { background: var(--color-accent); }
.nav-arrow-btn:disabled { opacity: 0.3; cursor: not-allowed; }

#practice-legend {
  display: flex;
  gap: 12px;
  padding: 6px 20px;
  background: #f8fdf9;
  border-bottom: 1px solid #d8f3dc;
  flex-shrink: 0;
}
.legend-item {
  font-size: 0.7rem;
  padding: 2px 8px;
  border-radius: 3px;
  color: #fff;
  font-weight: 600;
}
.legend-vowel    { background: var(--color-cell-vowel); }
.legend-consonant{ background: var(--color-cell-cons); }
.legend-cluster  { background: var(--color-cell-clust); }

#practice-grid-wrapper {
  flex: 1;
  overflow: auto;
  padding: 16px 20px 24px;
}

#practice-grid {
  display: grid;
  gap: var(--cell-gap);
}

.pcell {
  width: var(--cell-size);
  height: var(--cell-size);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
  font-size: var(--cell-font);
  font-weight: 600;
  cursor: pointer;
  border: none;
  text-align: center;
  line-height: 1.2;
  padding: 2px;
  transition: transform 0.1s, box-shadow 0.1s;
  white-space: pre-wrap;
  word-break: normal;
  overflow-wrap: break-word;
}
.pcell:hover { transform: scale(1.06); z-index: 1; box-shadow: 0 2px 8px rgba(0,0,0,0.25); }
.pcell:active { transform: scale(0.96); }
.pcell.playing {
  outline: 3px solid gold;
  outline-offset: 1px;
  transform: scale(1.06);
}

.pcell-vowel   { background: var(--color-cell-vowel);  color: #fff; font-size: 1.3rem; white-space: nowrap; }
.pcell-cons    { background: var(--color-cell-cons);   color: #fff; }
.pcell-cluster { background: var(--color-cell-clust);  color: #fff; }
.pcell-header  {
  background: var(--color-cell-header);
  color: var(--color-sidebar);
  cursor: default;
  font-size: 1.5rem;
  white-space: nowrap;
}
.pcell-empty {
  background: transparent;
  cursor: default;
}
.pcell-header:hover, .pcell-empty:hover { transform: none; box-shadow: none; }

/* ── Challenge view ──────────────────────────────────────────────────────── */
#challenge-header {
  padding: 16px 20px 8px;
  background: #fff;
  border-bottom: 2px solid #ffd6d3;
  flex-shrink: 0;
}
#challenge-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-challenge);
}
#challenge-subtitle {
  font-size: 0.8rem;
  color: var(--color-muted);
  margin-top: 2px;
}

/* Selector */
#challenge-selector { padding: 20px; }
#challenge-selector h3 { margin-bottom: 14px; color: var(--color-sidebar); font-size: 1rem; }
#challenge-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  max-width: 700px;
}
.ch-select-btn {
  padding: 10px 18px;
  border-radius: var(--radius);
  border: 2px solid var(--color-accent2);
  background: #fff;
  color: var(--color-sidebar);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s;
}
.ch-select-btn:hover { background: var(--color-accent2); color: #fff; }
.ch-select-btn.sample { border-color: #aaa; color: #777; }
.ch-select-btn.sample:hover { background: #aaa; color: #fff; }

/* Round */
#challenge-round { padding: 20px; flex: 1; overflow-y: auto; }

.phase-title {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-accent);
  margin-bottom: 4px;
}
.phase-desc {
  font-size: 0.85rem;
  color: var(--color-muted);
  line-height: 1.6;
  margin-bottom: 20px;
}

/* Listen buttons */
#listen-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 24px;
}
.listen-btn {
  width: 72px;
  height: 72px;
  border-radius: var(--radius);
  background: var(--color-num-btn);
  color: #fff;
  font-size: 1.8rem;
  font-weight: 700;
  border: 3px solid transparent;
  cursor: pointer;
  transition: border-color 0.2s, transform 0.1s, background 0.15s;
}
.listen-btn:hover { background: #2750b3; }
.listen-btn.heard { border-color: #f0c040; }
.listen-btn.playing {
  transform: scale(1.08);
  border-color: orange;
  background: #2750b3;
}

/* Answer cards */
#answer-cards-label,
#answer-slots-label {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--color-muted);
  margin-bottom: 8px;
  margin-top: 16px;
}
#answer-cards {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 4px;
}
.answer-card {
  padding: 8px 14px;
  border-radius: var(--radius);
  background: #e8f5e9;
  border: 2px solid #a5d6a7;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  color: var(--color-sidebar);
  user-select: none;
  transition: background 0.15s, border-color 0.15s, opacity 0.15s;
}
.answer-card:hover { background: #c8e6c9; border-color: #66bb6a; }
.answer-card.selected {
  background: var(--color-accent2);
  border-color: var(--color-accent);
  color: #fff;
}
.answer-card.assigned { opacity: 0.45; cursor: not-allowed; }
.answer-card.selected.assigned { opacity: 1; }

/* Answer slots */
#answer-slots {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 4px;
}
.answer-slot {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 2px dashed #aaa;
  border-radius: var(--radius);
  min-width: 120px;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
}
.answer-slot:hover { border-color: var(--color-accent2); background: #f0fff4; }
.answer-slot .slot-num {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-num-btn);
  min-width: 20px;
}
.answer-slot .slot-val {
  font-size: 0.85rem;
  color: var(--color-muted);
}
.answer-slot.filled { border-style: solid; border-color: var(--color-accent); }
.answer-slot.filled .slot-val { color: var(--color-text); font-weight: 600; }
.answer-slot.correct { border-color: #2e7d32; background: #e8f5e9; }
.answer-slot.wrong   { border-color: #c62828; background: #ffebee; }

#answer-actions {
  display: flex;
  gap: 12px;
  margin-top: 24px;
  flex-wrap: wrap;
}

/* Result */
#result-score {
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-sidebar);
  margin-bottom: 16px;
}
#result-detail {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 24px;
  max-width: 480px;
}
.result-row {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 12px;
  border-radius: var(--radius);
  font-size: 0.9rem;
}
.result-row.correct { background: #e8f5e9; }
.result-row.wrong   { background: #ffebee; }
.result-row .r-num  { font-size: 1.1rem; font-weight: 700; color: var(--color-num-btn); min-width: 24px; }
.result-row .r-icon { font-size: 1.1rem; }
.result-row .r-user { flex: 1; font-weight: 500; }
.result-row .r-correct { color: #c62828; font-size: 0.8rem; }
#result-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

/* Buttons */
.btn-primary {
  padding: 10px 22px;
  border-radius: var(--radius);
  background: var(--color-accent);
  color: #fff;
  border: none;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
}
.btn-primary:hover { background: var(--color-sidebar); }

.btn-secondary {
  padding: 10px 18px;
  border-radius: var(--radius);
  background: #fff;
  color: var(--color-sidebar);
  border: 2px solid var(--color-accent2);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s;
}
.btn-secondary:hover { background: #d8f3dc; }

.btn-back {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 6px 14px;
  border-radius: var(--radius);
  background: none;
  color: var(--color-accent);
  border: 1.5px solid var(--color-accent2);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
  margin-bottom: 0.5rem;
}
.btn-back:hover { background: #d8f3dc; color: var(--color-sidebar); }

/* ── Listening Exercise view ─────────────────────────────────────────────── */

#listening-header { padding: 1.5rem 2rem 0.5rem; }
#listening-header h2 { font-size: 1.4rem; margin: 0 0 0.25rem; color: var(--color-sidebar); }
#listening-header p  { margin: 0; color: #555; font-size: 0.9rem; }

#listening-selector { padding: 1rem 2rem 2rem; }
#listening-selector h3 { font-size: 1rem; margin: 0 0 1rem; color: #555; }

#listening-grid {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  max-width: 600px;
}

.lx-select-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: 0.75rem 1.1rem;
  background: #fff;
  border: 2px solid var(--color-accent2);
  border-radius: var(--radius);
  cursor: pointer;
  text-align: left;
  transition: background 0.15s, border-color 0.15s;
}
.lx-select-card:hover { background: #e8f5e9; border-color: var(--color-accent); }

.lx-card-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-text);
}
.lx-card-desc {
  font-size: 0.78rem;
  color: #666;
  margin-top: 0.2rem;
}

#listening-round { padding: 1rem 2rem 2rem; display: flex; flex-direction: column; gap: 1rem; }

.lx-hint {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-sidebar);
  background: #f0f9f4;
  border-left: 4px solid var(--color-accent);
  padding: 0.5rem 0.9rem;
  border-radius: 0 var(--radius) var(--radius) 0;
  margin: 0;
}

.lx-label {
  font-size: 0.82rem;
  color: #555;
  font-weight: 600;
  margin-bottom: 0.4rem;
  margin-top: 0.5rem;
}

#lx-word-cards {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.lx-word-card {
  padding: 0.55rem 1.1rem;
  background: #fff;
  border: 2px solid #bbb;
  border-radius: var(--radius);
  font-size: 1.05rem;
  font-weight: 700;
  cursor: pointer;
  transition: background 0.12s, border-color 0.12s;
  user-select: none;
}
.lx-word-card:hover { background: #c8e6c9; border-color: #66bb6a; }
.lx-word-card.selected { background: #43a047; color: #fff; border-color: #2e7d32; }
.lx-word-card.assigned { opacity: 0.45; cursor: not-allowed; }
.lx-word-card.selected.assigned { opacity: 1; }

#lx-word-slots {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.lx-word-slot {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-width: 80px;
  padding: 0.5rem 0.75rem;
  background: #f9f9f9;
  border: 2px dashed #bbb;
  border-radius: var(--radius);
  cursor: pointer;
  transition: border-color 0.12s, background 0.12s;
  gap: 0.25rem;
}
.lx-word-slot:hover { border-color: var(--color-accent2); background: #f0fff4; }
.lx-word-slot .slot-num { font-size: 0.75rem; color: #888; font-weight: 700; }
.lx-word-slot .slot-val { font-size: 0.95rem; font-weight: 700; color: #aaa; }
.lx-word-slot.filled { border-style: solid; border-color: var(--color-accent); }
.lx-word-slot.filled .slot-val { color: var(--color-text); }
.lx-word-slot.correct { border-color: #2e7d32; background: #e8f5e9; }
.lx-word-slot.correct .slot-val { color: #2e7d32; }
.lx-word-slot.wrong   { border-color: #c62828; background: #ffebee; }
.lx-word-slot.wrong   .slot-val { color: #c62828; }

#lx-answer-actions { display: flex; flex-wrap: wrap; gap: 0.6rem; margin-top: 0.5rem; }
#lx-result-actions  { display: flex; flex-wrap: wrap; gap: 0.6rem; margin-top: 0.5rem; }

#lx-result-score {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-sidebar);
  margin-bottom: 0.75rem;
}

/* ── Auth pages (signin.html / signup.html) ──────────────────────────────── */
body.auth-page {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  height: auto;
  overflow: auto;
  background: var(--color-bg);
}

.auth-container {
  width: 100%;
  max-width: 420px;
  padding: 2rem 1rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
}

.auth-logo {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.auth-logo-jp {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--color-sidebar);
  letter-spacing: 0.02em;
}

.auth-logo-en {
  font-size: 0.8rem;
  color: var(--color-muted);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.auth-card {
  width: 100%;
  background: #fff;
  border: 1px solid #d8f3dc;
  border-radius: var(--radius);
  box-shadow: 0 2px 12px rgba(0,0,0,0.08);
  padding: 2rem;
}

.auth-title {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--color-sidebar);
  margin-bottom: 1.5rem;
  text-align: center;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-bottom: 1rem;
}

.form-group label {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--color-text);
}

.form-input {
  padding: 10px 12px;
  border: 2px solid #a5d6a7;
  border-radius: var(--radius);
  font-size: 0.9rem;
  font-family: inherit;
  color: var(--color-text);
  background: #fff;
  transition: border-color 0.15s;
  outline: none;
}
.form-input:focus { border-color: var(--color-accent); }
.form-input::placeholder { color: #aaa; }

.form-error {
  font-size: 0.78rem;
  color: var(--color-challenge);
  min-height: 1em;
}

.form-check {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 1.25rem;
}
.form-check input[type="checkbox"] {
  width: 16px;
  height: 16px;
  accent-color: var(--color-accent);
  cursor: pointer;
}
.form-check label {
  font-size: 0.85rem;
  color: var(--color-muted);
  cursor: pointer;
}

.auth-submit {
  width: 100%;
  padding: 12px;
  font-size: 1rem;
  margin-top: 0.5rem;
}

.auth-switch {
  text-align: center;
  font-size: 0.85rem;
  color: var(--color-muted);
  margin-top: 1.25rem;
}

.auth-link {
  color: var(--color-accent);
  font-weight: 600;
  text-decoration: none;
}
.auth-link:hover { color: var(--color-sidebar); text-decoration: underline; }

/* Auth tabs */
.auth-tabs {
  display: flex;
  border-bottom: 2px solid #d8f3dc;
  margin-bottom: 1.5rem;
}

.auth-tab {
  flex: 1;
  padding: 10px;
  background: none;
  border: none;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-muted);
  cursor: pointer;
  border-bottom: 3px solid transparent;
  margin-bottom: -2px;
  transition: color 0.15s, border-color 0.15s;
}
.auth-tab:hover { color: var(--color-accent); }
.auth-tab.active {
  color: var(--color-sidebar);
  border-bottom-color: var(--color-accent);
}

/* Sign-out button in sidebar */
#btn-signout {
  display: block;
  width: calc(100% - 16px);
  margin: 8px;
  padding: 8px 12px;
  background: rgba(255,255,255,0.08);
  color: rgba(255,255,255,0.75);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: var(--radius);
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  text-align: left;
  transition: background 0.15s, color 0.15s;
}
#btn-signout:hover { background: rgba(255,255,255,0.18); color: #fff; }

#sidebar-user {
  padding: 10px 14px 4px;
  font-size: 0.75rem;
  color: rgba(255,255,255,0.55);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ── Mobile ──────────────────────────────────────────────────────────────── */
@media (max-width: 640px) {
  body { flex-direction: column; height: auto; overflow: auto; }
  #sidebar { width: 100%; min-width: 0; }
  #nav-sections { max-height: 40vh; }
  #main { height: auto; overflow: visible; }
  .view { display: none; }
  .view.active { display: flex; }
  :root { --cell-size: 56px; --cell-font: 0.6rem; }
  .listen-btn { width: 58px; height: 58px; font-size: 1.4rem; }
  .home-hero { padding: 2rem 1.5rem; }
}