/* ===== Nihongo Bắt Đầu — stylesheet ===== */
:root{
  --bg:#fdfaf6;
  --bg-card:#ffffff;
  --bg-raised:#fff9f2;
  --text:#2b2320;
  --text-muted:#7a6f68;
  --accent:#d1293d;
  --accent-dark:#a81f30;
  --accent-soft:#fbe3e6;
  --success:#2f9e58;
  --success-soft:#e2f5e8;
  --warning:#c98a12;
  --warning-soft:#fbf0da;
  --border:#ecdfd6;
  --shadow:rgba(43,35,32,0.08);
  --radius:16px;
  --radius-sm:10px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark){
  :root{
    --bg:#181614;
    --bg-card:#241f1c;
    --bg-raised:#2b2521;
    --text:#f2ece7;
    --text-muted:#b6a89f;
    --accent:#ff5d70;
    --accent-dark:#ff8290;
    --accent-soft:#3a2226;
    --success:#4fbf7c;
    --success-soft:#1d3327;
    --warning:#e0b13d;
    --warning-soft:#3a2f16;
    --border:#3a332f;
    --shadow:rgba(0,0,0,0.35);
    color-scheme: dark;
  }
}

*,*::before,*::after{box-sizing:border-box;}
html,body{margin:0;padding:0;}
body{
  background:var(--bg);
  color:var(--text);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Hiragino Kaku Gothic ProN","Yu Gothic","Noto Sans JP","Helvetica Neue",Arial,sans-serif;
  line-height:1.55;
  min-height:100vh;
  display:flex;
  flex-direction:column;
}
.jp{font-family:"Hiragino Mincho ProN","Hiragino Kaku Gothic ProN","Yu Gothic","Noto Sans JP","Noto Serif JP",serif;}
a{color:inherit;}
button{font:inherit;}
h1,h2,h3,h4{margin:0 0 .4em;line-height:1.3;}
p{margin:0 0 .6em;}

/* ---- layout shell ---- */
.app-header{
  position:sticky;top:0;z-index:20;
  background:var(--bg);
  border-bottom:1px solid var(--border);
  backdrop-filter:blur(6px);
}
.app-header-inner{
  max-width:920px;margin:0 auto;padding:12px 16px;
  display:flex;align-items:center;gap:12px;flex-wrap:wrap;
}
.brand{
  font-weight:800;font-size:1.15rem;letter-spacing:.2px;
  display:flex;align-items:center;gap:8px;text-decoration:none;color:var(--text);
  margin-right:auto;
}
.brand-mark{
  width:34px;height:34px;border-radius:10px;background:var(--accent);
  color:#fff;display:flex;align-items:center;justify-content:center;font-weight:900;font-size:1rem;
  flex-shrink:0;
}
.stat-pill{
  display:flex;align-items:center;gap:6px;
  background:var(--bg-card);border:1px solid var(--border);
  padding:6px 12px;border-radius:999px;font-weight:700;font-size:.9rem;
  box-shadow:0 1px 2px var(--shadow);
}
.stat-pill.streak{color:var(--accent);}
@keyframes flame-pulse{0%,100%{transform:scale(1);}50%{transform:scale(1.15);}}
.stat-pill.streak.lit{animation:flame-pulse 1.6s ease-in-out infinite;}
.stat-pill.xp{color:var(--warning);flex-direction:column;align-items:stretch;gap:3px;padding:5px 12px;}
.xp-mini-bar{width:60px;height:4px;border-radius:999px;background:var(--border);overflow:hidden;}
.xp-mini-bar i{display:block;height:100%;background:var(--warning);border-radius:999px;transition:width .3s ease;}
.nav-tabs{
  display:flex;gap:4px;max-width:920px;margin:0 auto;padding:0 16px 10px;
}
.nav-tabs a{
  text-decoration:none;color:var(--text-muted);font-weight:600;font-size:.92rem;
  padding:6px 12px;border-radius:999px;
}
.nav-tabs a.active{background:var(--accent-soft);color:var(--accent-dark);}

.settings-panel{
  max-width:920px;margin:0 auto;padding:12px 16px 16px;
  border-top:1px solid var(--border);
  display:flex;flex-direction:column;gap:12px;
}
.settings-row{display:flex;flex-direction:column;gap:6px;}
.settings-row label{font-size:.85rem;font-weight:700;color:var(--text-muted);}
.settings-row select,.settings-row input[type="range"]{width:100%;}
.settings-row select{
  padding:8px 10px;border-radius:var(--radius-sm);border:1px solid var(--border);
  background:var(--bg-card);color:var(--text);font-size:.92rem;
}
.settings-hint{color:var(--text-muted);font-size:.8rem;background:var(--warning-soft);padding:8px 12px;border-radius:var(--radius-sm);}

main{max-width:920px;margin:0 auto;padding:20px 16px 90px;width:100%;flex:1;}

/* ---- auth / profiles ---- */
.auth-wrap{max-width:420px;margin:0 auto;display:flex;flex-direction:column;gap:16px;}
.auth-brand{text-align:center;display:flex;flex-direction:column;align-items:center;gap:8px;margin-bottom:4px;}
.auth-brand .brand-mark{background:var(--accent);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:900;}
.auth-brand h2{margin:0;}
.auth-card h3{margin-bottom:10px;}
.auth-card input[type="text"],.auth-card input[type="password"]{
  width:100%;padding:11px 14px;border-radius:var(--radius-sm);border:1px solid var(--border);
  background:var(--bg-card);color:var(--text);font-size:1rem;margin-bottom:8px;box-sizing:border-box;
}
.auth-error{color:var(--accent-dark);font-size:.85rem;font-weight:700;}
.auth-profile-list{display:flex;flex-direction:column;gap:8px;}
.auth-profile-row{
  display:flex;align-items:center;gap:10px;width:100%;padding:12px 14px;
  border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--bg-raised);
  cursor:pointer;font-size:1rem;font-weight:700;text-align:left;
}
.auth-profile-row:hover{border-color:var(--accent);}
.auth-profile-avatar{font-size:1.2rem;}
.auth-profile-name{flex:1;}

.app-footer{
  border-top:1px solid var(--border);
  padding:18px 16px 26px;
  text-align:center;
  color:var(--text-muted);
  font-size:.82rem;
}
.app-footer b{color:var(--text);}

/* ---- cards / grid ---- */
.grid{display:grid;gap:14px;}
.grid-cards{grid-template-columns:repeat(auto-fill,minmax(260px,1fr));}
.card{
  background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius);
  padding:18px;box-shadow:0 1px 3px var(--shadow);
}
.card-link{display:block;text-decoration:none;color:inherit;transition:transform .15s ease, box-shadow .15s ease;}
.card-link:hover{transform:translateY(-2px);box-shadow:0 6px 16px var(--shadow);}

.lesson-card .lesson-num{
  display:inline-block;background:var(--accent);color:#fff;font-weight:800;font-size:.75rem;
  padding:3px 9px;border-radius:999px;margin-bottom:8px;
}
.lesson-card h3{font-size:1.05rem;}
.lesson-card .jp-title{color:var(--text-muted);font-size:.95rem;}

.progress-bar{
  height:8px;border-radius:999px;background:var(--border);overflow:hidden;margin:10px 0 4px;
}
.progress-bar > i{display:block;height:100%;background:var(--success);border-radius:999px;transition:width .3s ease;}
.progress-label{font-size:.78rem;color:var(--text-muted);}

.topic-card{border-left:4px solid var(--accent);}
.topic-card-head{display:flex;align-items:center;gap:14px;margin-bottom:8px;}
.topic-card-head h3{margin-bottom:2px;}
.mini-ring{position:relative;width:56px;height:56px;flex-shrink:0;}
.mini-ring .progress-ring{position:absolute;inset:0;transform:rotate(-90deg);}
.mini-ring .ring-bg{fill:none;stroke:var(--border);}
.mini-ring .ring-fg{fill:none;stroke:var(--success);stroke-linecap:round;transition:stroke-dashoffset .6s ease;}
.mini-ring-label{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;font-size:.72rem;font-weight:800;color:var(--text);}
.topic-card .can-do{color:var(--text-muted);font-size:.92rem;margin-bottom:10px;}
.topic-actions{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px;}

.btn{
  border:none;cursor:pointer;border-radius:999px;padding:9px 18px;font-weight:700;font-size:.92rem;
  background:var(--accent);color:#fff;transition:filter .15s ease, transform .1s ease;
  display:inline-flex;align-items:center;gap:6px;
}
.btn:hover{filter:brightness(1.06);}
.btn:active{transform:scale(.97);}
.btn.secondary{background:var(--bg-raised);color:var(--text);border:1px solid var(--border);}
.btn.success{background:var(--success);}
.btn.ghost{background:transparent;color:var(--accent);padding:9px 12px;}
.btn.big{padding:14px 24px;font-size:1.02rem;width:100%;justify-content:center;}
.btn:disabled{opacity:.5;cursor:not-allowed;}
.btn-icon{width:38px;height:38px;padding:0;justify-content:center;border-radius:50%;}

.breadcrumb{color:var(--text-muted);font-size:.85rem;margin-bottom:12px;}
.breadcrumb a{text-decoration:none;color:var(--text-muted);}
.breadcrumb a:hover{color:var(--accent);}

/* ---- lesson list (sequential, lockable) ---- */
.lesson-list{display:flex;flex-direction:column;gap:12px;}
.lesson-row{
  display:flex;align-items:center;gap:14px;text-decoration:none;color:inherit;
  background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius);
  padding:14px 16px;box-shadow:0 1px 3px var(--shadow);transition:transform .15s ease,box-shadow .15s ease;
}
.lesson-row:not(.locked):hover{transform:translateX(3px);box-shadow:0 4px 12px var(--shadow);border-color:var(--accent);}
.lesson-row.locked{opacity:.55;cursor:not-allowed;}
.lesson-row-badge{
  flex-shrink:0;width:48px;height:48px;border-radius:50%;background:var(--accent-soft);color:var(--accent-dark);
  display:flex;align-items:center;justify-content:center;font-weight:900;font-size:1.3rem;
}
.lesson-row-badge.done{background:var(--success);color:#fff;}
.lesson-row-badge.locked{background:var(--border);color:var(--text-muted);font-size:1.1rem;}
.lesson-row-body{flex:1;min-width:0;}
.lesson-row-title{font-weight:700;margin-bottom:4px;}
.lesson-row-title .jp{font-weight:800;}
.path-trophy-inline{font-size:.95em;}
.lesson-row-arrow{flex-shrink:0;font-size:1.6rem;color:var(--text-muted);}

/* ---- game-y micro interactions ---- */
@keyframes pop-in{from{transform:scale(.85);opacity:0;}to{transform:scale(1);opacity:1;}}
@keyframes shake{10%,90%{transform:translateX(-2px);}20%,80%{transform:translateX(4px);}30%,50%,70%{transform:translateX(-8px);}40%,60%{transform:translateX(8px);}}
@keyframes bounce-correct{0%{transform:scale(1);}30%{transform:scale(1.05);}60%{transform:scale(.98);}100%{transform:scale(1);}}
@keyframes float-up-fade{0%{transform:translateY(0);opacity:1;}100%{transform:translateY(-40px);opacity:0;}}
.quiz-option.correct{animation:bounce-correct .35s ease;}
.quiz-option.wrong{animation:shake .35s ease;}
.flashcard-face.back{animation:pop-in .3s ease;}
.xp-float{
  position:fixed;font-weight:900;color:var(--success);font-size:1.1rem;pointer-events:none;
  animation:float-up-fade 1s ease forwards;z-index:200;transform:translateX(-50%);
}

/* ---- flashcards ---- */
.flash-wrap{display:flex;flex-direction:column;align-items:center;gap:18px;}
.flash-progress-block{width:100%;max-width:440px;display:flex;flex-direction:column;gap:6px;}
.flash-progress-row{display:flex;justify-content:space-between;align-items:center;width:100%;}
.flash-progress{color:var(--text-muted);font-size:.9rem;}
.flash-progress-pct{color:var(--success);font-weight:800;font-size:.95rem;}
.flashcard{
  width:100%;max-width:440px;min-height:260px;perspective:1200px;cursor:pointer;
}
.flashcard-inner{
  position:relative;width:100%;height:100%;min-height:260px;
  transform-style:preserve-3d;transform:rotateY(0deg);
}
@keyframes card-flip{
  0%{transform:rotateY(0deg) scale(1);}
  45%{transform:rotateY(90deg) scale(1.07);}
  100%{transform:rotateY(180deg) scale(1);}
}
.flashcard.flipped .flashcard-inner{animation:card-flip .5s cubic-bezier(.2,.8,.2,1) forwards;}
.flashcard-face{
  position:absolute;inset:0;backface-visibility:hidden;
  background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius);
  display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;
  padding:24px;box-shadow:0 4px 14px var(--shadow);gap:8px;
}
.flashcard-face.back{transform:rotateY(180deg);}
.flashcard-illustration{font-size:2.6rem;line-height:1;margin-bottom:2px;}
.flashcard-jp{font-size:2.1rem;font-weight:700;}
.flashcard-kana{color:var(--text-muted);font-size:1.05rem;}
.flashcard-romaji{color:var(--accent);font-size:.95rem;font-style:italic;}
.flashcard-vi{font-size:1.4rem;font-weight:700;}
.flashcard-note{color:var(--text-muted);font-size:.85rem;max-width:320px;}
.flashcard-mnemonic{color:var(--warning);font-size:.85rem;max-width:340px;font-style:italic;background:var(--warning-soft);padding:8px 12px;border-radius:var(--radius-sm);}
.flash-hint{color:var(--text-muted);font-size:.8rem;}
.flash-controls{display:flex;gap:12px;width:100%;max-width:440px;}
.flash-controls .btn{flex:1;}

/* ---- dialogue ---- */
.dialogue-line{
  display:flex;gap:10px;margin-bottom:14px;align-items:flex-start;
}
.dialogue-line.speaker-b{flex-direction:row-reverse;text-align:right;}
.speaker-avatar{
  width:34px;height:34px;border-radius:50%;background:var(--accent-soft);color:var(--accent-dark);
  display:flex;align-items:center;justify-content:center;font-weight:800;flex-shrink:0;
}
.dialogue-line.speaker-b .speaker-avatar{background:var(--warning-soft);color:var(--warning);}
.dialogue-bubble{
  background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius-sm);
  padding:10px 14px;max-width:78%;
}
.dialogue-jp{font-size:1.15rem;font-weight:600;}
.dialogue-kana{color:var(--text-muted);font-size:.85rem;}
.dialogue-romaji{color:var(--accent);font-size:.85rem;font-style:italic;}
.dialogue-vi{margin-top:4px;font-size:.92rem;color:var(--text-muted);}
.dialogue-line.speaker-b .dialogue-bubble{margin-left:auto;}
.dialogue-line-speak{
  flex-shrink:0;width:32px;height:32px;border-radius:50%;align-self:center;
  border:1px solid var(--border);background:var(--bg-card);cursor:pointer;font-size:.95rem;color:var(--accent);
}
.dialogue-line-speak:hover{border-color:var(--accent);background:var(--accent-soft);}

/* ---- quiz ---- */
.quiz-progress{display:flex;align-items:center;gap:10px;margin-bottom:18px;}
.quiz-progress .progress-bar{flex:1;margin:0;}
.quiz-question{text-align:center;margin-bottom:22px;}
.quiz-question .prompt-label{color:var(--text-muted);font-size:.85rem;margin-bottom:8px;}
.quiz-question .prompt-main{font-size:1.9rem;font-weight:700;}
.quiz-question .prompt-sub{color:var(--text-muted);font-size:1rem;margin-top:4px;}
.quiz-options{display:grid;gap:10px;grid-template-columns:1fr;}
@media(min-width:520px){.quiz-options{grid-template-columns:1fr 1fr;}}
.quiz-option{
  background:var(--bg-card);border:2px solid var(--border);border-radius:var(--radius-sm);
  padding:14px 16px;text-align:left;cursor:pointer;font-size:1.02rem;font-weight:600;width:100%;
}
.quiz-option:hover{border-color:var(--accent);}
.quiz-option.correct{border-color:var(--success);background:var(--success-soft);}
.quiz-option.wrong{border-color:var(--accent);background:var(--accent-soft);}
.quiz-option.disabled{pointer-events:none;}
.quiz-option-wrap{display:flex;gap:6px;align-items:stretch;}
.quiz-option-wrap .quiz-option{flex:1;min-width:0;}
.quiz-option-speak{
  flex-shrink:0;width:44px;border:2px solid var(--border);border-radius:var(--radius-sm);
  background:var(--bg-card);cursor:pointer;font-size:1.15rem;color:var(--accent);
}
.quiz-option-speak:hover{border-color:var(--accent);background:var(--accent-soft);}
.quiz-feedback{text-align:center;margin-top:16px;font-weight:700;}
.quiz-feedback.correct{color:var(--success);}
.quiz-feedback.wrong{color:var(--accent-dark);}
.quiz-summary{text-align:center;}
.quiz-summary .score-big{font-size:3rem;font-weight:800;color:var(--accent);}
.final-exam-summary{border:3px solid var(--border);}
.final-exam-summary.passed{border-color:var(--success);background:linear-gradient(180deg,var(--success-soft),var(--bg-card) 40%);}
.final-exam-summary.failed{border-color:var(--warning);}
.final-exam-badge{font-size:3.5rem;line-height:1;margin-bottom:4px;}
.final-exam-summary.passed .score-big{color:var(--success);}
.review-list{text-align:left;margin-top:18px;}
.review-item{
  display:flex;justify-content:space-between;gap:10px;padding:8px 0;border-bottom:1px solid var(--border);
}

/* ---- stats ---- */
.stats-grid{display:grid;gap:14px;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));margin-bottom:18px;}
.stat-box{background:var(--bg-card);border:1px solid var(--border);border-radius:var(--radius);padding:16px;text-align:center;}
.stat-box .big{font-size:1.7rem;font-weight:800;color:var(--accent);}
.stat-box .label{color:var(--text-muted);font-size:.82rem;}
.calendar-strip{display:flex;gap:5px;flex-wrap:wrap;}
.cal-dot{
  width:26px;height:26px;border-radius:8px;background:var(--border);
  display:flex;align-items:center;justify-content:center;font-size:.68rem;color:var(--text-muted);
}
.cal-dot.active{background:var(--success);color:#fff;}
.badge-row{display:flex;gap:10px;flex-wrap:wrap;margin-top:8px;}
.badge{
  background:var(--warning-soft);color:var(--warning);border-radius:999px;padding:6px 12px;font-size:.82rem;font-weight:700;
}
.badge.locked{opacity:.4;}

.empty-state{text-align:center;color:var(--text-muted);padding:40px 20px;}

.toast{
  position:fixed;bottom:20px;left:50%;transform:translateX(-50%);
  background:var(--text);color:var(--bg);padding:12px 20px;border-radius:999px;
  font-weight:700;box-shadow:0 6px 20px var(--shadow);z-index:100;
  animation:toast-in .25s ease;
}
@keyframes toast-in{from{opacity:0;transform:translate(-50%,10px);}to{opacity:1;transform:translate(-50%,0);}}

.section-title{display:flex;align-items:center;justify-content:space-between;margin-bottom:12px;}
.section-title h2{margin:0;font-size:1.15rem;}

@media(max-width:480px){
  .flashcard-jp{font-size:1.7rem;}
  .quiz-question .prompt-main{font-size:1.5rem;}
}

/* ---- Certificate (canvas is drawn at 1600x1131, scaled responsively) ---- */
.certificate-wrap{max-width:900px;margin:0 auto;}
.certificate-wrap canvas{
  display:block;width:100%;height:auto;border-radius:10px;
  box-shadow:0 10px 34px var(--shadow);
}