/*
============================================================================
PROJECTE: Motor Educatiu d'Integrals (Vanilla JS)
FITXER: css/integrals.css
ROL: Estils específics per al joc d'integrals.
ARQUITECTURA:
- Sobreescriu les variables de shared.css per adaptar els colors al joc.
  Paleta: verd esmeralda (#059669), mirall de derivades.css en estructura.
- Defineix la graella d'opcions (CSS Grid) i els contenidors de KaTeX.
- Gestiona les animacions d'encert, error i estats dels botons.
- Conté estils per al feedback ampliat:
    .feedback-correct  → text verd d'encert
    .feedback-wrong    → text fosc d'error
    .hint-box          → bloc explicatiu del tipus d'error conceptual
    .solution-reveal   → fila amb la primitiva correcta (KaTeX)
    .solution-label    → etiqueta "La primitiva correcta era:"
    .solution-formula  → fórmula KaTeX de la solució
DEPENDÈNCIES: S'ha de carregar DESPRÉS de shared.css.
============================================================================
*/
:root {
    --bg-color:      #f0fdf4;
    --primary:       #059669;
    --primary-light: #d1fae5;
    --primary-dark:  #065f46;
    --primary-hover: #047857;
    --text-main:     #1e293b;
    --text-muted:    #64748b;
    --border-light:  #e2e8f0;
    --border-heavy:  #cbd5e1;
    --success:       #10b981;
    --danger:        #ef4444;
    --danger-light:  #fee2e2;
}

/* ---- CONTENIDOR DE L'ENUNCIAT ---- */
.function-box {
    padding: 15px 20px;
    padding-left: 15px;
    text-align: left;
    display: flex;
    justify-content: flex-start;
    align-items: center;
    flex-direction: row;
    flex-wrap: wrap;
    gap: 15px;
    font-size: 1.5em;
    font-weight: bold;
    min-height: 80px;
    max-width: 780px;
    margin: 0 auto;
}

.function-label {
    color: var(--text-muted);
    font-size: 0.9em;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.function-math {
    font-size: 1.1em;
    color: var(--primary-dark);
    padding: 10px 30px;
    background: #f3f4f6;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    border: 2px solid var(--border-light);
}

.function-math .katex-display {
    margin: 5px 0;
}

/* ---- GRAELLA DE BOTONS ---- */
.options-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 15px;
    width: 100%;
    max-width: 780px;
    margin: 20px auto;
    padding: 0 15px;
}

@keyframes popIn {
    0%   { opacity: 0; transform: scale(0.95); }
    100% { opacity: 1; transform: scale(1); }
}

.btn-option {
    padding: 16px 12px;
    font-size: 1.3em;
    border-radius: 12px;
    border: 2px solid var(--border-heavy);
    background: white;
    color: var(--text-main);
    cursor: pointer;
    transition: background 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 80px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    opacity: 0;
    animation: popIn 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275) forwards;
    overflow: hidden;
    min-width: 0;
}

.btn-option:focus-visible {
    outline: 3px solid var(--primary);
    outline-offset: 2px;
}

/* KaTeX dins botons: escalat automàtic per a expressions llargues */
.btn-option .katex-html {
    max-width: 100%;
    overflow-x: auto;
    overflow-y: hidden;
    scrollbar-width: none;
}
.btn-option .katex-html::-webkit-scrollbar { display: none; }

@media (hover: hover) {
    .btn-option:hover {
        background: var(--primary-light);
        border-color: var(--primary);
        transform: translateY(-2px);
    }
}

.btn-option:active { transform: scale(0.97); }

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25%      { transform: translateX(-5px); }
    75%      { transform: translateX(5px); }
}

.btn-option.error-shake {
    background-color: var(--danger-light) !important;
    border-color:     var(--danger) !important;
    color:            var(--danger) !important;
    animation: shake 0.3s;
}

.btn-option.correct {
    background-color: var(--success) !important;
    border-color:     var(--success) !important;
    color:            white !important;
}

.btn-option.wrong {
    background-color: var(--danger-light) !important;
    border-color:     var(--danger) !important;
    color:            var(--danger) !important;
    pointer-events:   none;
    opacity:          0.7;
}

/* ================================================================
   FEEDBACK AMPLIAT
   ================================================================ */

/* Text d'encert */
.feedback-correct {
    color: var(--success);
}

/* Text d'error (nivell 1) */
.feedback-wrong {
    color:       var(--text-main);
    font-weight: normal;
}

/* Hint ampliat (nivell 2) */
.hint-box {
    margin-top:    8px;
    padding:       10px 16px;
    background:    #fffbeb;
    border-left:   4px solid #f59e0b;
    border-radius: 0 8px 8px 0;
    color:         #78350f;
    font-size:     0.92em;
    font-weight:   normal;
    line-height:   1.5;
    text-align:    left;
    animation:     fadeInDown 0.3s ease;
}

/* Botó que desplega el hint */
.hint-toggle-btn {
    display:       inline-block;
    margin-top:    8px;
    padding:       3px 10px;
    font-size:     0.78em;
    font-weight:   600;
    color:         #92400e;
    background:    #fef3c7;
    border:        1px solid #f59e0b;
    border-radius: 99px;
    cursor:        pointer;
    transition:    background 0.15s ease;
    user-select:   none;
}
.hint-toggle-btn:hover { background: #fde68a; }

@keyframes fadeInDown {
    from { opacity: 0; transform: translateY(-6px); }
    to   { opacity: 1; transform: translateY(0); }
}

/* Primitiva correcta (nivell 3): apareix quan s'esgoten els intents */
.solution-reveal {
    display:         flex;
    align-items:     center;
    justify-content: center;
    flex-wrap:       wrap;
    gap:             10px;
    margin-top:      12px;
    padding:         10px 16px;
    background:      #f0fdf4;
    border:          2px solid #bbf7d0;
    border-radius:   8px;
    animation:       fadeInDown 0.4s ease;
}

.solution-label {
    color:          #047857;
    font-size:      0.9em;
    font-weight:    600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    white-space:    nowrap;
}

.solution-formula {
    color:     #065f46;
    font-size: 1.1em;
}

/* ================================================================
   RESPONSIU
   ================================================================ */

@media (max-width: 480px) {
    .options-grid {
        grid-template-columns: 1fr;
        gap: 10px;
    }
    .function-math {
        font-size: 1.2em;
        padding: 10px 20px;
    }
    .btn-option {
        min-height: 70px;
        font-size:  1.1em;
        padding:    15px 10px;
    }
    .hint-box {
        font-size: 0.88em;
        padding:   8px 12px;
    }
    .solution-reveal {
        flex-direction: column;
        gap: 6px;
    }
}

/* Animació de pèrdua d'intent */
@keyframes attemptsBlink {
    0%, 100% { background-color: #d1fae5; border-color: #d1d5db; color: #334155; }
    50%      { background-color: #e5e7eb; border-color: #059669; color: #334155; }
}

.attempts-counter.blink {
    animation: attemptsBlink 0.2s linear 5;
}

/* ================================================================
   RESUM PEDAGÒGIC DE SESSIÓ (#session-summary)
   ================================================================ */

#session-summary {
    padding:   24px 20px 28px;
    animation: fadeInDown 0.4s ease;
}

/* Puntuació total */
.summary-score {
    display:       flex;
    flex-direction:column;
    align-items:   center;
    gap:           4px;
    margin-bottom: 20px;
}
.summary-score-label {
    font-size:      0.85em;
    text-transform: uppercase;
    letter-spacing: 1px;
    color:          var(--text-muted);
}
.summary-score-value {
    font-size:   2em;
    font-weight: 800;
    color:       var(--primary-dark);
}

/* Tres estadístiques */
.summary-stats {
    display:         flex;
    justify-content: center;
    gap:             12px;
    margin-bottom:   24px;
    flex-wrap:       wrap;
}
.summary-stat {
    display:         flex;
    flex-direction:  column;
    align-items:     center;
    gap:             4px;
    padding:         12px 16px;
    border-radius:   10px;
    min-width:       90px;
    border:          2px solid transparent;
}
.summary-stat--ok   { background: #f0fdf4; border-color: #bbf7d0; }
.summary-stat--warn { background: #fffbeb; border-color: #fde68a; }
.summary-stat--err  { background: #fef2f2; border-color: #fecaca; }

.summary-stat-num {
    font-size:   1.8em;
    font-weight: 800;
    line-height: 1;
}
.summary-stat--ok   .summary-stat-num { color: #047857; }
.summary-stat--warn .summary-stat-num { color: #b45309; }
.summary-stat--err  .summary-stat-num { color: #b91c1c; }

.summary-stat-desc {
    font-size:  0.78em;
    text-align: center;
    color:      var(--text-muted);
    line-height:1.3;
}

/* Títol de la secció d'errors */
.summary-errors-title {
    font-size:      0.82em;
    text-transform: uppercase;
    letter-spacing: 1px;
    color:          var(--text-muted);
    font-weight:    700;
    margin-bottom:  10px;
    text-align:     center;
}

/* Llista d'errors conceptuals */
.summary-errors-list {
    display:       flex;
    flex-direction:column;
    gap:           8px;
    margin-bottom: 24px;
}
.summary-error-item {
    background:    #fffbeb;
    border-left:   4px solid #f59e0b;
    border-radius: 0 8px 8px 0;
    padding:       10px 14px;
    animation:     fadeInDown 0.3s ease;
}
.summary-error-header {
    display:         flex;
    justify-content: space-between;
    align-items:     baseline;
    gap:             8px;
    margin-bottom:   4px;
}
.summary-error-type {
    font-weight: 700;
    font-size:   0.92em;
    color:       #78350f;
}
.summary-error-count {
    font-size:     0.78em;
    color:         #92400e;
    white-space:   nowrap;
    background:    #fef3c7;
    padding:       1px 8px;
    border-radius: 99px;
}
.summary-error-hint {
    font-size:   0.88em;
    color:       #78350f;
    line-height: 1.5;
}

/* Missatge quan no hi ha errors */
.summary-no-errors {
    text-align:    center;
    color:         #047857;
    font-weight:   600;
    font-size:     1em;
    background:    #f0fdf4;
    border:        2px solid #bbf7d0;
    border-radius: 10px;
    padding:       14px;
    margin-bottom: 24px;
}

/* Botó de continuar */
.summary-continue-btn {
    display:       block;
    margin:        0 auto;
    padding:       12px 36px;
    background:    var(--primary);
    color:         white;
    border:        none;
    border-radius: 10px;
    font-size:     1em;
    font-weight:   700;
    cursor:        pointer;
    transition:    background 0.2s ease, transform 0.15s ease;
}
.summary-continue-btn:hover  { background: var(--primary-hover); transform: translateY(-1px); }
.summary-continue-btn:active { transform: scale(0.97); }

@media (max-width: 480px) {
    .summary-stats   { gap: 8px; }
    .summary-stat    { min-width: 75px; padding: 10px 10px; }
    .summary-stat-num{ font-size: 1.5em; }
}