/* SIE Flashcard Styles
 * Mobile-first design for swipe-based flashcard training
 * Uses existing design tokens from main.css
 */

/* ============================================
   Flashcard App Container - Dark theme default
   ============================================ */
.flashcard-app {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    min-height: 100dvh; /* Dynamic viewport height for mobile */
    min-height: -webkit-fill-available; /* iOS Safari fallback */
    background: #1a1f2e; /* Dark blue-gray, easy on eyes */
    overflow: hidden;
    /* Safe area insets for notched devices */
    padding-left: env(safe-area-inset-left);
    padding-right: env(safe-area-inset-right);
    padding-bottom: env(safe-area-inset-bottom);
}

/* ============================================
   Header - Compact for mobile
   ============================================ */
.flashcard-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--fh-space-xs) var(--fh-space-md);
    padding-top: calc(var(--fh-space-xs) + env(safe-area-inset-top));
    background: var(--fh-navy);
    color: var(--fh-white);
    /* Leave room for back button on left */
    padding-left: 72px;
    min-height: 44px;
    flex-shrink: 0;
}

@media (max-width: 360px) {
    .flashcard-header {
        padding-left: 64px;
        padding-right: var(--fh-space-sm);
    }
}

.flashcard-title {
    font-family: var(--fh-font-display);
    font-size: 1rem;
    font-weight: 600;
    color: var(--fh-white);
    margin: 0;
}

.flashcard-stats {
    display: flex;
    align-items: center;
    gap: var(--fh-space-xs);
    font-size: 0.8125rem;
    font-weight: 500;
    opacity: 0.95;
}

.stat-divider {
    opacity: 0.5;
}

/* ============================================
   Start Screen
   ============================================ */
.flashcard-start-screen {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: var(--fh-space-xl);
    text-align: center;
}

.start-content {
    max-width: 320px;
    width: 100%;
}

/* Progress Ring */
.progress-ring {
    position: relative;
    width: 120px;
    height: 120px;
    margin: 0 auto var(--fh-space-xl);
}

.progress-ring svg {
    transform: rotate(-90deg);
    width: 100%;
    height: 100%;
}

.progress-ring__bg {
    fill: none;
    stroke: rgba(255, 255, 255, 0.1);
    stroke-width: 8;
}

.progress-ring__fill {
    fill: none;
    stroke: var(--fh-sage);
    stroke-width: 8;
    stroke-linecap: round;
    transition: stroke-dashoffset 0.5s ease;
}

.progress-ring__text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-family: var(--fh-font-display);
    font-size: 1.75rem;
    font-weight: 600;
    color: #e8eaed;
}

.start-title {
    font-family: var(--fh-font-display);
    font-size: 1.75rem;
    color: #e8eaed;
    margin-bottom: var(--fh-space-sm);
}

.start-description {
    color: rgba(255, 255, 255, 0.6);
    margin-bottom: var(--fh-space-xl);
}

/* Session Options */
.session-options {
    margin-top: var(--fh-space-xl);
}

.option-label {
    display: flex;
    flex-direction: column;
    gap: var(--fh-space-sm);
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.6);
}

.option-select {
    padding: var(--fh-space-sm) var(--fh-space-md);
    font-family: var(--fh-font-body);
    font-size: 1rem;
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 8px;
    background: #2a3142;
    color: #e8eaed;
    cursor: pointer;
}

.option-select:focus {
    outline: 2px solid transparent; /* visible in forced-colors/high-contrast mode */
    border-color: var(--fh-sage);
    box-shadow: 0 0 0 3px rgba(124, 152, 133, 0.2);
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--fh-space-md) var(--fh-space-xl);
    font-family: var(--fh-font-body);
    font-size: 1rem;
    font-weight: 500;
    text-decoration: none;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition:
        transform 0.15s ease,
        box-shadow 0.15s ease,
        background-color 0.15s ease;
    min-height: 48px; /* Touch target */
    min-width: 48px;
}

.btn--primary {
    background: var(--fh-navy);
    color: var(--fh-white);
}

.btn--primary:hover {
    background: #003a7d;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 45, 98, 0.3);
}

.btn--primary:active {
    transform: translateY(0);
}

.btn--secondary {
    background: transparent;
    color: var(--fh-navy);
    border: 2px solid var(--fh-navy);
}

.btn--secondary:hover {
    background: rgba(0, 45, 98, 0.05);
}

.btn--start {
    width: 100%;
    padding: var(--fh-space-lg) var(--fh-space-xl);
    font-size: 1.125rem;
}

/* ============================================
   Session View - Optimized for iPhone 12 Pro
   ============================================ */
.flashcard-session {
    flex: 1;
    display: flex;
    flex-direction: column;
    padding: var(--fh-space-sm) var(--fh-space-md);
    padding-bottom: 0;
    overflow: hidden;
    min-height: 0; /* Allow flex shrinking */
    gap: var(--fh-space-xs);
}

/* Progress Bar - More prominent */
.session-progress {
    display: flex;
    align-items: center;
    gap: var(--fh-space-md);
    flex-shrink: 0;
}

.progress-bar {
    flex: 1;
    height: 8px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 4px;
    overflow: hidden;
}

.progress-bar__fill {
    height: 100%;
    background: linear-gradient(90deg, var(--fh-sage), #8fb099);
    border-radius: 4px;
    transition: width 0.3s ease;
}

.progress-text {
    font-size: 0.875rem;
    font-weight: 600;
    color: rgba(255, 255, 255, 0.7);
    white-space: nowrap;
    font-family: var(--fh-font-mono);
    min-width: 5ch;
    text-align: right;
}

/* Session Counter - Compact inline display */
.session-counter {
    display: flex;
    justify-content: center;
    gap: var(--fh-space-xl);
    flex-shrink: 0;
}

.counter {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: var(--fh-space-sm);
}

.counter__value {
    font-size: 1.5rem;
    font-weight: 700;
    font-family: var(--fh-font-mono);
    min-width: 2ch;
    text-align: center;
}

.counter__label {
    font-size: 0.75rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.02em;
    color: rgba(255, 255, 255, 0.5);
}

.counter--got-it .counter__value {
    color: var(--fh-sage);
}

.counter--dont-know .counter__value {
    color: var(--fh-burgundy);
}

/* Stacked counters on larger screens */
@media (min-width: 500px) {
    .counter {
        flex-direction: column;
        gap: var(--fh-space-xs);
    }

    .counter__value {
        font-size: 1.75rem;
    }

    .counter__label {
        font-size: 0.8125rem;
    }
}

/* ============================================
   Flashcard - Optimized for iPhone 12 Pro (390x844)
   ============================================ */
.flashcard-container {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    perspective: 1000px;
    touch-action: none; /* Enable custom touch handling */
    user-select: none;
    min-height: 0; /* Allow flex shrinking */
    padding: var(--fh-space-sm);
}

.flashcard {
    width: 100%;
    max-width: 380px;
    /* Height adapts to content */
    height: auto;
    min-height: 200px;
    cursor: pointer;
    transform-style: preserve-3d;
    transform-origin: center center;
    transition: transform 0.35s ease;
}

/* iPhone 12 Pro and similar (390px width, 844px height) */
@media (min-width: 380px) and (min-height: 800px) {
    .flashcard {
        max-width: 360px;
        min-height: 220px;
    }
}

/* Larger phones and tablets */
@media (min-height: 900px) {
    .flashcard {
        max-width: 420px;
        min-height: 240px;
    }
}

.flashcard--flipped {
    transform: rotateY(180deg);
}

.flashcard__inner {
    position: relative;
    width: 100%;
    min-height: 100%;
    transform-style: preserve-3d;
    transform-origin: center center;
}

.flashcard__front,
.flashcard__back {
    display: flex;
    /* Center content vertically and horizontally */
    align-items: center;
    justify-content: center;
    padding: var(--fh-space-xl);
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    transform-origin: center center;
    border-radius: 20px;
    box-shadow:
        0 8px 32px rgba(0, 0, 0, 0.3),
        0 16px 48px rgba(0, 0, 0, 0.2);
    overflow: hidden;
    -webkit-overflow-scrolling: touch;
    /* Ensure minimum height for short content */
    min-height: 200px;
}

/* Front is in normal flow, determines card size */
.flashcard__front {
    position: relative;
    width: 100%;
    background: #2a3142; /* Soft dark blue-gray */
    border: 1px solid rgba(255, 255, 255, 0.08);
}

/* Back is absolutely positioned on top of front */
.flashcard__back {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: #1e3a5f; /* Deep navy, slightly lighter than before */
    color: var(--fh-white);
    transform: rotateY(180deg);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

/* Even more padding on larger screens */
@media (min-width: 500px) {
    .flashcard__front,
    .flashcard__back {
        padding: var(--fh-space-2xl);
        border-radius: 24px;
    }
}

.flashcard__text {
    font-family: var(--fh-font-body);
    font-size: clamp(1.125rem, 5vw, 1.625rem);
    line-height: 1.5;
    text-align: center;
    margin: 0;
    /* Ensure text stays within card bounds */
    width: 100%;
    max-width: 100%;
    word-wrap: break-word;
    overflow-wrap: break-word;
    hyphens: auto;
    -webkit-hyphens: auto;
}

.flashcard__front .flashcard__text {
    color: #e8eaed; /* Soft white, not harsh */
    font-weight: 500;
}

.flashcard__back .flashcard__text {
    color: #f0f4f8; /* Slightly warm white */
    font-weight: 400;
    /* Support line breaks in content */
    white-space: pre-line;
}

/* Formula styling - monospace for calculations */
.flashcard__formula {
    display: block;
    font-family: var(--fh-font-mono);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--fh-gold);
    margin-bottom: var(--fh-space-md);
    letter-spacing: 0.02em;
}

/* Back content wrapper - stacks answer and tip vertically */
.flashcard__back-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 100%;
    max-width: 100%;
}

/* Memory Aid - tip shown below the answer */
.flashcard__memory-aid {
    display: block;
    width: 100%;
    margin-top: var(--fh-space-lg);
    padding-top: var(--fh-space-md);
    border-top: 1px solid rgba(255, 255, 255, 0.15);
    font-size: 0.9rem;
    font-style: italic;
    color: var(--fh-sage);
    text-align: center;
    line-height: 1.5;
}

/* Hide empty memory aids */
.flashcard__memory-aid:empty {
    display: none;
}

/* Swipe visual feedback - Brand colors */
.flashcard--swiping-horizontal {
    box-shadow: 0 0 30px rgba(107, 39, 55, 0.4);
}

.flashcard--swiping-up {
    box-shadow: 0 0 30px rgba(124, 152, 133, 0.5);
}

/* ============================================
   Action Buttons - Large tap targets for mobile
   ============================================ */
.action-buttons {
    display: flex;
    justify-content: center;
    gap: var(--fh-space-md);
    padding: var(--fh-space-md);
    padding-bottom: calc(var(--fh-space-lg) + env(safe-area-inset-bottom));
    flex-shrink: 0;
}

.action-btn {
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: center;
    gap: var(--fh-space-sm);
    padding: var(--fh-space-md) var(--fh-space-xl);
    flex: 1;
    max-width: 180px;
    min-height: 60px;
    font-family: var(--fh-font-body);
    font-size: 0.9375rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.02em;
    border: none;
    border-radius: 16px;
    cursor: pointer;
    transition:
        transform 0.12s ease,
        box-shadow 0.12s ease;
    -webkit-tap-highlight-color: transparent;
}

.action-btn__icon {
    font-size: 1.5rem;
    line-height: 1;
}

.action-btn--dont-know {
    background: var(--fh-burgundy);
    color: var(--fh-white);
    box-shadow: 0 4px 12px rgba(107, 39, 55, 0.3);
}

.action-btn--dont-know:hover {
    background: #7a3040;
    box-shadow: 0 6px 16px rgba(107, 39, 55, 0.4);
}

.action-btn--dont-know:active {
    transform: scale(0.97);
    box-shadow: 0 2px 8px rgba(107, 39, 55, 0.3);
}

.action-btn--got-it {
    background: var(--fh-sage);
    color: var(--fh-white);
    box-shadow: 0 4px 12px rgba(124, 152, 133, 0.3);
}

.action-btn--got-it:hover {
    background: #8ba990;
    box-shadow: 0 6px 16px rgba(124, 152, 133, 0.4);
}

.action-btn--got-it:active {
    transform: scale(0.97);
    box-shadow: 0 2px 8px rgba(124, 152, 133, 0.3);
}

/* Full-width buttons on very small screens */
@media (max-width: 360px) {
    .action-buttons {
        flex-direction: column;
        gap: var(--fh-space-sm);
    }

    .action-btn {
        max-width: 100%;
    }
}

/* Hide action buttons on desktop (swipe/keyboard works well) */
@media (min-width: 768px) and (hover: hover) {
    .action-buttons {
        display: none;
    }
}

/* ============================================
   Swipe Hints (hidden - users discover gestures naturally)
   ============================================ */
.swipe-hints,
.tap-hint {
    display: none;
}

/* ============================================
   Session Summary
   ============================================ */
.flashcard-summary {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--fh-space-lg);
    padding-bottom: calc(var(--fh-space-lg) + env(safe-area-inset-bottom));
}

.summary-content {
    text-align: center;
    max-width: 400px;
    width: 100%;
}

.summary-title {
    font-family: var(--fh-font-display);
    font-size: 1.75rem;
    color: #e8eaed; /* Soft white for dark theme */
    margin-bottom: var(--fh-space-lg);
}

@media (min-width: 400px) {
    .summary-title {
        font-size: 2rem;
        margin-bottom: var(--fh-space-xl);
    }
}

.summary-stats {
    display: flex;
    justify-content: center;
    gap: var(--fh-space-lg);
    margin-bottom: var(--fh-space-xl);
}

@media (min-width: 400px) {
    .summary-stats {
        gap: var(--fh-space-xl);
        margin-bottom: var(--fh-space-2xl);
    }
}

.summary-stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--fh-space-xs);
}

.summary-stat__value {
    font-family: var(--fh-font-display);
    font-size: 2rem;
    font-weight: 600;
    color: #e8eaed; /* Soft white for dark theme */
}

@media (min-width: 400px) {
    .summary-stat__value {
        font-size: 2.5rem;
    }
}

.summary-stat--proficient .summary-stat__value {
    color: var(--fh-sage);
}

.summary-stat--learning .summary-stat__value {
    color: var(--fh-gold);
}

.summary-stat__label {
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.5);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

@media (min-width: 400px) {
    .summary-stat__label {
        font-size: 0.875rem;
    }
}

.summary-actions {
    display: flex;
    flex-direction: column;
    gap: var(--fh-space-md);
}

.summary-actions .btn {
    min-height: 52px;
}

/* ============================================
   Responsive Adjustments
   ============================================ */
@media (min-width: 768px) {
    .flashcard {
        width: 70%;
        max-width: 500px;
    }

    .swipe-hints {
        max-width: 500px;
        margin-left: auto;
        margin-right: auto;
    }

    .summary-actions {
        flex-direction: row;
        justify-content: center;
    }
}

@media (min-width: 1024px) {
    .flashcard-app {
        max-width: 800px;
        margin: 0 auto;
        min-height: calc(100vh - 4rem);
        border-radius: 0 0 16px 16px;
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
    }
}

/* ============================================
   Landscape Mode - Horizontal layout for phones
   ============================================ */
@media (max-height: 500px) and (orientation: landscape) {
    .flashcard-header {
        padding-top: var(--fh-space-xs);
        padding-bottom: var(--fh-space-xs);
        min-height: 36px;
    }

    .flashcard-title {
        font-size: 0.875rem;
    }

    .flashcard-stats {
        font-size: 0.75rem;
    }

    .flashcard-session {
        flex-direction: row;
        padding: var(--fh-space-xs) var(--fh-space-md);
        gap: var(--fh-space-md);
    }

    .session-progress {
        display: none; /* Hide progress bar in landscape */
    }

    .session-counter {
        flex-direction: column;
        justify-content: center;
        gap: var(--fh-space-sm);
        min-width: 80px;
    }

    .counter {
        flex-direction: row;
        gap: var(--fh-space-xs);
    }

    .counter__value {
        font-size: 1.25rem;
    }

    .counter__label {
        font-size: 0.625rem;
    }

    .flashcard-container {
        flex: 1;
        padding: var(--fh-space-xs);
    }

    .flashcard {
        max-width: none;
        max-height: 100%;
        min-height: 180px;
    }

    .flashcard__front,
    .flashcard__back {
        padding: var(--fh-space-md);
        border-radius: 12px;
    }

    .flashcard__text {
        font-size: clamp(0.9375rem, 3vw, 1.25rem);
    }

    .action-buttons {
        flex-direction: column;
        justify-content: center;
        padding: var(--fh-space-xs);
        padding-right: calc(var(--fh-space-sm) + env(safe-area-inset-right));
        padding-bottom: var(--fh-space-xs);
        gap: var(--fh-space-sm);
    }

    .action-btn {
        flex-direction: column;
        min-width: 70px;
        max-width: 70px;
        min-height: 70px;
        padding: var(--fh-space-sm);
        font-size: 0.625rem;
        gap: 2px;
    }

    .action-btn__icon {
        font-size: 1.25rem;
    }
}

/* ============================================
   Accessibility
   ============================================ */
@media (prefers-reduced-motion: reduce) {
    .flashcard,
    .progress-bar__fill,
    .progress-ring__fill,
    .btn {
        transition: none;
    }

    .flashcard--flipped {
        transform: none;
    }

    .flashcard--flipped .flashcard__front {
        visibility: hidden;
    }

    .flashcard--flipped .flashcard__back {
        transform: none;
        visibility: visible;
    }
}

/* Focus styles for keyboard navigation */
.btn:focus-visible {
    outline: 3px solid var(--fh-gold);
    outline-offset: 2px;
}

.flashcard:focus-visible {
    outline: 3px solid var(--fh-gold);
    outline-offset: 4px;
}