/* ===================================
   CSS Variables & Reset
   =================================== */
:root {
    --color-primary: #6366f1;
    --color-primary-hover: #4f46e5;
    --color-success: #22c55e;
    --color-error: #ef4444;
    --color-bg: #0f172a;
    --color-card: #1e293b;
    --color-text: #f8fafc;
    --color-text-muted: #94a3b8;
    --color-border: #334155;
    
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    --radius-sm: 0.5rem;
    --radius-md: 1rem;
    --radius-lg: 1.5rem;
    
    --tap-target: 44px;
    
    /* Safe area insets for iOS notches */
    --safe-top: env(safe-area-inset-top, 0px);
    --safe-bottom: env(safe-area-inset-bottom, 0px);
    --safe-left: env(safe-area-inset-left, 0px);
    --safe-right: env(safe-area-inset-right, 0px);
}

*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===================================
   Main App Container
   =================================== */
#app {
    height: 100%;
    width: 100%;
    display: flex;
    flex-direction: column;
    padding: var(--safe-top) var(--safe-right) var(--safe-bottom) var(--safe-left);
    overflow-y: auto;
    overflow-x: hidden;
    -webkit-overflow-scrolling: touch;
}

/* ===================================
   Screen Base Styles
   =================================== */
.screen {
    min-height: 100%;
    display: flex;
    flex-direction: column;
    padding: var(--spacing-lg);
    animation: fadeIn 0.3s ease-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Reduced motion preference */
@media (prefers-reduced-motion: reduce) {
    .screen {
        animation: none !important;
    }
    
    .result-icon.visible {
        animation: none !important;
    }
    
    .media-status .spinner {
        animation: none !important;
    }
    
    button {
        transition: none !important;
    }
    
    .progress-fill {
        transition: none !important;
    }
}

/* ===================================
   Card Component
   =================================== */
.card {
    background-color: var(--color-card);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    gap: var(--spacing-md);
}

/* ===================================
   Typography
   =================================== */
.title {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.subtitle {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-md);
}

.text {
    font-size: 1rem;
    color: var(--color-text);
    line-height: 1.7;
}

.text-muted {
    color: var(--color-text-muted);
}

/* ===================================
   Buttons
   =================================== */
button {
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    border: none;
    border-radius: var(--radius-md);
    min-height: var(--tap-target);
    padding: var(--spacing-sm) var(--spacing-lg);
    transition: transform 0.15s ease, background-color 0.15s ease, opacity 0.15s ease;
}

button:focus-visible {
    outline: 3px solid var(--color-primary);
    outline-offset: 2px;
}

button:active {
    transform: scale(0.98);
}

.btn-primary {
    background-color: var(--color-primary);
    color: white;
    width: 100%;
    max-width: 300px;
}

.btn-primary:hover:not(:disabled) {
    background-color: var(--color-primary-hover);
}

.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.btn-secondary {
    background-color: var(--color-border);
    color: var(--color-text);
}

.btn-secondary:hover:not(:disabled) {
    background-color: #475569;
}

.btn-secondary:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.btn-play {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    background-color: var(--color-primary);
    color: white;
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1.125rem;
}

.btn-play.playing {
    background-color: var(--color-success);
}

/* ===================================
   Form Elements
   =================================== */
.form-group {
    width: 100%;
    max-width: 300px;
    text-align: left;
}

label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-xs);
}

select {
    width: 100%;
    min-height: var(--tap-target);
    padding: var(--spacing-sm);
    font-family: inherit;
    font-size: 1rem;
    background-color: var(--color-bg);
    color: var(--color-text);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.75rem center;
    background-size: 1rem;
    padding-right: 2.5rem;
}

select:focus {
    outline: none;
    border-color: var(--color-primary);
}

select:invalid {
    color: var(--color-text-muted);
}

/* ===================================
   Progress Indicator
   =================================== */
.progress {
    font-size: 0.875rem;
    color: var(--color-text-muted);
    margin-bottom: var(--spacing-sm);
}

.progress-bar {
    width: 100%;
    height: 4px;
    background-color: var(--color-border);
    border-radius: 2px;
    overflow: hidden;
    margin-bottom: var(--spacing-lg);
}

.progress-fill {
    height: 100%;
    background-color: var(--color-primary);
    transition: width 0.3s ease;
}

/* ===================================
   Quiz Screen
   =================================== */
.quiz-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-lg);
    padding: var(--spacing-lg) 0;
}

.quiz-nav {
    display: flex;
    gap: var(--spacing-sm);
    width: 100%;
    max-width: 300px;
}

.quiz-nav button {
    flex: 1;
}

/* ===================================
   Results Screen
   =================================== */
.results-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-lg);
}

.score-display {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-md);
}

.score-number {
    font-size: 4rem;
    font-weight: 700;
    color: var(--color-primary);
    line-height: 1;
}

.score-total {
    font-size: 1.25rem;
    color: var(--color-text-muted);
}

.icons-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-xs);
    max-width: 320px;
    padding: var(--spacing-sm);
}

.result-icon {
    width: 28px;
    height: 28px;
    opacity: 0;
    transform: scale(0);
    flex-shrink: 0;
}

.result-icon.visible {
    animation: popIn 0.3s ease forwards;
}

/* Handle reduced motion - make icons visible without animation */
@media (prefers-reduced-motion: reduce) {
    .result-icon {
        opacity: 1;
        transform: scale(1);
    }
    
    .result-icon.visible {
        animation: none;
    }
}

@keyframes popIn {
    0% {
        opacity: 0;
        transform: scale(0);
    }
    70% {
        transform: scale(1.2);
    }
    100% {
        opacity: 1;
        transform: scale(1);
    }
}

.checkmark-icon {
    color: var(--color-success);
}

.cross-icon {
    color: var(--color-error);
}

.success-message {
    font-size: 1.125rem;
    text-align: center;
    line-height: 1.7;
    padding: var(--spacing-md);
    background-color: rgba(34, 197, 94, 0.1);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-success);
}

/* ===================================
   Reward Viewer Screen
   =================================== */
.reward-viewer {
    height: 100%;
    display: flex;
    flex-direction: column;
}

.media-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    position: relative;
    background-color: #000;
    border-radius: var(--radius-md);
    overflow: hidden;
    min-height: 200px;
}

.media-container video {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.media-status {
    position: absolute;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--color-text);
}

.media-status .spinner {
    width: 48px;
    height: 48px;
    border: 3px solid var(--color-border);
    border-top-color: var(--color-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

/* Autoplay fallback overlay */
.autoplay-overlay {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: rgba(0, 0, 0, 0.8);
    gap: var(--spacing-md);
    z-index: 10;
}

.autoplay-overlay button {
    padding: var(--spacing-md) var(--spacing-xl);
}

.reward-nav {
    display: flex;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) 0;
}

.reward-nav button {
    flex: 1;
}

.skip-audio-container {
    display: flex;
    justify-content: center;
    padding: var(--spacing-sm) 0;
}

.btn-skip-audio {
    background-color: transparent;
    color: var(--color-text-muted);
    border: 1px solid var(--color-border);
    font-size: 0.875rem;
    padding: var(--spacing-xs) var(--spacing-md);
}

.btn-skip-audio:hover:not(:disabled) {
    background-color: var(--color-border);
    color: var(--color-text);
}

.fragment-indicator {
    text-align: center;
    padding: var(--spacing-sm) 0;
    color: var(--color-text-muted);
    font-size: 0.875rem;
}

/* ===================================
   Confetti Canvas
   =================================== */
#confetti-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 1000;
}

/* ===================================
   Hidden Elements
   =================================== */
#audio-player,
#video-player {
    position: absolute;
    opacity: 0;
    pointer-events: none;
    width: 0;
    height: 0;
}

/* ===================================
   Media Queries
   =================================== */
@media (min-width: 480px) {
    .title {
        font-size: 2rem;
    }
    
    .card {
        padding: var(--spacing-xl);
    }
    
    .score-number {
        font-size: 5rem;
    }
}

@media (min-width: 768px) {
    .screen {
        max-width: 600px;
        margin: 0 auto;
    }
}