/* Learn page: tabs, knowledge cards, flashcards, quiz, browse toolbar */

.learn-intro {
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
}

/* --- Mode tabs --- */

.learn-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.learn-tab {
    padding: 6px 16px;
    border: 1px solid var(--color-border);
    border-radius: 6px;
    background: var(--color-white);
    color: var(--color-text-light);
    font-size: var(--font-size-small);
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.learn-tab:hover,
.learn-tab.active {
    background: var(--color-primary);
    border-color: var(--color-primary);
    color: #fff;
}

.learn-panel[hidden] {
    display: none;
}

/* --- Shared buttons and toolbar --- */

.learn-btn {
    padding: 6px 16px;
    border: 1px solid var(--color-border);
    border-radius: 6px;
    background: var(--color-white);
    color: var(--color-text);
    font-size: var(--font-size-small);
    font-family: inherit;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.learn-btn:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.learn-btn.primary {
    background: var(--color-primary);
    border-color: var(--color-primary);
    color: #fff;
}

.learn-btn.primary:hover {
    background: var(--color-primary-hover);
    border-color: var(--color-primary-hover);
}

.learn-actions {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.learn-toolbar {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.learn-toolbar input[type="search"],
.learn-toolbar select {
    padding: 6px 10px;
    border: 1px solid var(--color-border);
    border-radius: 6px;
    background: var(--color-white);
    color: var(--color-text);
    font-size: var(--font-size-small);
    font-family: inherit;
}

.learn-toolbar input[type="search"] {
    flex: 1 1 220px;
    min-width: 160px;
}

.learn-count {
    color: var(--color-text-light);
    font-size: var(--font-size-small);
    margin-left: auto;
}

.learn-stats {
    color: var(--color-text-light);
    font-size: var(--font-size-small);
    margin-bottom: var(--spacing-sm);
}

/* --- Knowledge cards (Daily, Browse) --- */

.k-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.k-card {
    background: var(--color-white);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: var(--spacing-md);
    transition: opacity var(--transition-fast);
}

.k-head {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xs);
    font-size: var(--font-size-small);
}

.k-badge {
    display: inline-block;
    padding: 1px 10px;
    border: 1px solid currentColor;
    border-radius: 999px;
    font-weight: 600;
    text-transform: capitalize;
}

.k-badge--principle { color: var(--color-primary); }
.k-badge--term      { color: var(--color-info); }
.k-badge--insight   { color: var(--color-success); }
.k-badge--quote     { color: var(--color-text-light); }

.k-source {
    color: var(--color-text-light);
}

.k-done {
    margin-left: auto;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--color-text-light);
    cursor: pointer;
    user-select: none;
}

.k-title {
    font-weight: 600;
    color: var(--color-heading);
    margin-bottom: var(--spacing-xs);
}

.k-text {
    white-space: pre-line;
    overflow-wrap: anywhere;
}

.k-card.done {
    opacity: 0.45;
}

.learn-progress {
    height: 6px;
    background: var(--color-border);
    border-radius: 999px;
    overflow: hidden;
    margin: var(--spacing-sm) 0 var(--spacing-md);
}

.learn-progress span {
    display: block;
    height: 100%;
    width: 0;
    background: var(--color-primary);
    transition: width var(--transition-normal);
}

/* --- Flashcards --- */

.flashcard {
    background: var(--color-white);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: var(--spacing-lg);
    min-height: 220px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: var(--spacing-sm);
    text-align: center;
}

.flashcard-meta {
    color: var(--color-text-light);
    font-size: var(--font-size-small);
}

.flashcard-front {
    font-size: var(--font-size-large);
    font-weight: 600;
    color: var(--color-heading);
}

.flashcard-back {
    display: none;
    white-space: pre-line;
    text-align: left;
    border-top: 1px solid var(--color-border);
    padding-top: var(--spacing-sm);
}

.flashcard.revealed .flashcard-back {
    display: block;
}

.learn-btn.good { color: var(--color-success); }
.learn-btn.again { color: var(--color-warning); }

.learn-btn.good:hover { border-color: var(--color-success); }
.learn-btn.again:hover { border-color: var(--color-warning); }

.learn-keys {
    color: var(--color-text-light);
    font-size: var(--font-size-small);
    margin-top: var(--spacing-sm);
}

/* --- Quiz --- */

.quiz-question {
    background: var(--color-white);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    white-space: pre-line;
}

.quiz-options {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.quiz-option {
    text-align: left;
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    background: var(--color-white);
    color: var(--color-text);
    font-family: inherit;
    font-size: var(--font-size-base);
    cursor: pointer;
    transition: border-color var(--transition-fast);
    white-space: pre-line;
    overflow-wrap: anywhere;
}

.quiz-option:hover:not(:disabled) {
    border-color: var(--color-primary);
}

.quiz-option:disabled {
    cursor: default;
}

.quiz-option.correct {
    border-color: var(--color-success);
    color: var(--color-success);
}

.quiz-option.wrong {
    border-color: var(--color-warning);
    color: var(--color-warning);
}

/* --- Empty / error states --- */

.learn-empty {
    text-align: center;
    color: var(--color-text-light);
    padding: var(--spacing-lg);
}

/* --- Responsive --- */

@media (max-width: 600px) {
    .learn-toolbar {
        flex-direction: column;
        align-items: stretch;
    }

    .learn-count {
        margin-left: 0;
    }

    .flashcard {
        padding: var(--spacing-md);
    }
}

@media (max-width: 480px) {
    .learn-tab,
    .learn-btn {
        font-size: var(--font-size-small);
        padding: 6px 12px;
    }

    .flashcard-front {
        font-size: var(--font-size-base);
    }
}