:root {
    --theme-primary: #9e78e8; /* Main Purple from main.css --secondary-color */
    --theme-primary-light: #b197f1;
    --theme-primary-dark: #8662c6;
    --theme-secondary-accent: #b197f1; /* Using light version as accent */
    --theme-primary-bg: #f5f2fe;
    --theme-secondary-bg: #ede9f9;
    --theme-text-on-primary: #ffffff;
    
    --app-bg-page: var(--theme-primary-bg);
    --app-border-color: #e2dcf4;
    --app-btn-disabled-bg: #d3c9ed;
    --app-btn-disabled-text: #8c81a2;
    --text-color-light: #888888;
}

.app-container {
    background-color: var(--light-gray, #fff);
    border: 1px solid var(--app-border-color);
    border-radius: 24px;
    margin-top: 2rem;
    text-align: left;
    overflow: hidden;
    transition: all 0.3s ease-in-out;
}

.app-header {
  display: grid;
  grid-template-columns: 1fr 13fr 1fr;
  align-items: center;
  gap: 1rem;
  padding: 0.5rem 1.5rem;
  background-color: var(--theme-primary);
  color: var(--theme-text-on-primary);
  border-bottom: 1px solid var(--theme-primary-dark);
}
.app-header-title {
    grid-column: 2;
    text-align: center;
    padding: 0 1rem;
}
.app-header h2 {
    font-size: 1.2rem;
    margin: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}
.app-content {
    padding: 1.5rem;
    text-align: center;
}
.btn-icon {
    justify-self: end;
    background: none;
    border: 1px solid transparent;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    color: var(--theme-text-on-primary);
    cursor: pointer;
    transition: background-color 0.2s ease;
}
.btn-icon:hover {
    background-color: rgba(255, 255, 255, 0.1);
}
.btn-icon .fa-compress {
    display: none;
}
.app-container.is-focused .btn-icon .fa-expand {
    display: none;
}
.app-container.is-focused .btn-icon .fa-compress {
    display: inline-block;
}

/* === Focus Mode === */
body.focus-mode-active {
    overflow: hidden;
}
body.focus-mode-active .site-header,
body.focus-mode-active .footer,
body.focus-mode-active .breadcrumbs,
body.focus-mode-active .sidebar,
body.focus-mode-active .content__main > *:not(.app-container) {
    display: none;
}

/* Overrides to ensure the container goes full screen */
body.focus-mode-active .content {
    max-width: none !important;
    padding: 0 !important;
}

body.focus-mode-active .content__main {
    margin-right: 0 !important;
    padding: 0 !important;
}

.app-container.is-focused {
    border-radius: 0;
    border: none;
    margin-top: 0;
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: calc(var(--vh, 1vh) * 100);
    z-index: 2000;
}
.app-container.is-focused .app-content {
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    overflow-y: auto;
}
.app-container.is-focused .flashcard-viewer {
    flex-grow: 1;
}


/* === Tabs === */
.sentence-randomizer__tabs {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.75rem;
    margin-bottom: 1.5rem;
    border-bottom: none;
}
.sentence-randomizer__tab {
    padding: 0.8rem 1.2rem;
    border: 2px solid var(--app-border-color);
    border-radius: 12px;
    background-color: #f9f9f9;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-color);
    position: relative;
    transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
    white-space: normal;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
}
.sentence-randomizer__tab:hover:not(.sentence-randomizer__tab--active) {
    background-color: var(--theme-secondary-bg);
    border-color: var(--theme-primary-light);
}
.sentence-randomizer__tab--active {
    background-color: var(--theme-primary);
    color: var(--theme-text-on-primary);
    border-color: var(--theme-primary-dark);
    box-shadow: 0 4px 8px rgba(158, 120, 232, 0.2);
}
.sentence-randomizer__tab--active::after {
    display: none;
}


/* === Flashcard Viewer (From card-shuffler) === */
.flashcard-viewer {
    display: flex;
    flex-direction: column;
    height: 100%;
}
.flashcard-status {
    display: flex;
    justify-content: center;
    margin-bottom: 0.25rem; /* Reduced space */
}
.progress-container {
    width: 100%;
    max-width: 400px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}
.card-counter {
    font-weight: 700;
    font-size: 1.2rem;
}
.progress-bar {
    width: 100%;
    height: 12px;
    background-color: var(--app-border-color);
    border-radius: 12px;
    overflow: hidden;
}
.progress-bar-inner {
    height: 100%;
    background-color: var(--theme-primary);
    transition: width 0.3s ease;
}

.flashcard-area {
    flex-grow: 1;
    perspective: 1000px;
    margin: 0.75rem 0 1.5rem; /* Reduced top margin, adjusted bottom */
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}
.flashcard {
    position: relative;
    width: 100%;
    max-width: 620px;
    aspect-ratio: 2 / 1;
    transform-style: preserve-3d;
    transition: transform 0.6s, max-width 0.3s ease, max-height 0.3s ease;
    border-radius: 48px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}
.flashcard.is-flipped {
    transform: rotateX(180deg);
}
.flashcard-face {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem 1rem;
    text-align: center;
    font-size: 4.5rem;
    line-height: 1.25;
    transition: font-size 0.3s ease, line-height 0.3s ease, padding 0.3s ease;
    border-radius: 48px;
}

/* Larger horizontal padding for the English side */
.flashcard-face.lang-en {
    padding-left: 2.5rem;
    padding-right: 2.5rem;
}

.flashcard-face.font-size-xl { font-size: 3rem; }
.flashcard-face.font-size-lg { font-size: 2.8rem; }
.flashcard-face.font-size-md { font-size: 2.4rem; }
.flashcard-face.font-size-sm { font-size: 2.1rem; }

.flashcard-front {
    background-color: #dcd0f9; /* A softer, lighter purple */
    color: var(--text-color); /* Dark text for better contrast */
}
.flashcard-back {
    background-color: var(--theme-secondary-bg);
    transform: rotateX(180deg);
}
.flashcard-face p.flashcard-intro-text {
  font-size: 1.5rem;
  font-weight: 500;
}
.flashcard-face p.flashcard-intro-text i {
  display: block;
  margin-bottom: 1rem;
  font-size: 2.5rem;
}

.flashcard-controls {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.5rem;
    margin-top: auto;
}
.flashcard-controls .btn {
    padding: 0.8rem 1.2rem;
    border: 1px solid transparent;
    border-radius: 12px;
    cursor: pointer;
    font-weight: 600;
    font-size: 0.9rem;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.flashcard-controls .btn-primary {
    background-color: var(--theme-primary);
    color: var(--theme-text-on-primary);
}
.flashcard-controls .btn-primary:hover:not(:disabled) {
    background-color: var(--theme-primary-dark);
}

.flashcard-controls .btn:disabled {
  background-color: var(--app-btn-disabled-bg);
  color: var(--app-btn-disabled-text);
  cursor: not-allowed;
  border-color: transparent;
}

/* Single-sided card for conversation questions */
.flashcard.single-sided .flashcard-back {
    display: none;
}
.flashcard.single-sided {
    transform-style: flat;
}


/* Completion Message */
.flashcard.is-completion-card .flashcard-face {
    padding: 1.5rem;
}
.flashcard.is-completion-card .flashcard-front {
    background-color: #d4edda;
    color: #155724;
}
.flashcard.is-completion-card .flashcard-back {
    display: none;
}
.completion-content {
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    line-height: 1.2;
}
.flashcard.is-completion-card .completion-content {
    display: flex;
}
.completion-icon {
    font-size: 3rem;
    color: #155724;
    margin-bottom: 1rem;
}
.completion-content h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}
.completion-content p {
    font-size: 1.2rem;
    margin: 0;
}

/* Responsive */
@media (max-width: 992px) {
    .flashcard-controls {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .app-content {
        padding: 1rem;
    }
    .flashcard {
        aspect-ratio: 5 / 3;
    }

    .sentence-randomizer__tab {
        padding: 0.8rem 0.5rem;
        font-size: 0.9rem;
    }
    
    .app-container.is-focused {
        position: static;
        height: auto;
        min-height: calc(var(--vh, 1vh) * 100);
    }
    .app-container.is-focused .app-content {
        overflow-y: visible;
    }
    body.focus-mode-active {
        overflow: auto;
    }

    /* Larger horizontal padding for the English side on mobile */
    .flashcard-face.lang-en {
        padding-left: 1.5rem;
        padding-right: 1.5rem;
    }

    .flashcard-face.font-size-xl { font-size: 2.5rem; }
    .flashcard-face.font-size-lg { font-size: 2.2rem; }
    .flashcard-face.font-size-md { font-size: 1.9rem; }
    .flashcard-face.font-size-sm { font-size: 1.7rem; }

    .completion-icon { font-size: 2.5rem; }
    .completion-content h3 { font-size: 1.3rem; }
    .completion-content p { font-size: 1rem; }
}

@media (min-width: 768px) {
    /* In focus mode, allow the card to grow a bit larger for a more immersive view, but constrain its max size. */
    .app-container.is-focused .flashcard {
        max-width: 700px;
        max-height: 350px;
    }

    /* Increase font sizes to match the larger card in focus mode */
    .app-container.is-focused .flashcard-face.font-size-xl { font-size: 3.5rem; }
    .app-container.is-focused .flashcard-face.font-size-lg { font-size: 3.2rem; }
    .app-container.is-focused .flashcard-face.font-size-md { font-size: 2.8rem; }
    .app-container.is-focused .flashcard-face.font-size-sm { font-size: 2.4rem; }
}


@media (max-width: 576px) {
    .sentence-randomizer__tabs {
        grid-template-columns: 1fr; /* Stack buttons on mobile */
    }
}

@media (max-width: 480px) {
     .flashcard-controls .btn {
        padding-left: 0.5rem;
        padding-right: 0.5rem;
        gap: 0.3rem;
    }
}

/* Styling for grammatical and lexical focus */
.flashcard-face b {
    font-weight: 800;
}

.flashcard-face u {
    text-decoration-color: var(--theme-primary-dark, #8662c6);
    text-decoration-thickness: 2px;
}