:root {
    --bg-color: #0f111a;
    --text-primary: #ffffff;
    --text-secondary: #a0aaec;
    --accent-color: #7c3aed; /* Violet */
    --accent-hover: #6d28d9;
    --success: #10b981;
    --error: #ef4444;
    --card-bg: rgba(23, 25, 35, 0.7);
    --card-border: rgba(255, 255, 255, 0.1);
    --blob-1: #4c1d95;
    --blob-2: #db2777;
    --blob-3: #2563eb;
    --font-main: 'Outfit', sans-serif;
}

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

body {
    font-family: var(--font-main);
    background-color: var(--bg-color);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow-x: hidden;
    position: relative;
}

/* Background Blobs */
.background-blobs {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    overflow: hidden;
    pointer-events: none;
}

.blob {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.4;
    animation: blob-bounce 20s infinite ease-in-out alternate;
}

.blob-1 {
    top: -10%;
    left: -10%;
    width: 500px;
    height: 500px;
    background: var(--blob-1);
    animation-delay: 0s;
}

.blob-2 {
    bottom: -10%;
    right: -10%;
    width: 400px;
    height: 400px;
    background: var(--blob-2);
    animation-delay: -5s;
}

.blob-3 {
    top: 40%;
    left: 40%;
    width: 300px;
    height: 300px;
    background: var(--blob-3);
    animation-delay: -10s;
}

@keyframes blob-bounce {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(50px, 50px) scale(1.1); }
}

/* App Container */
.app-container {
    width: 100%;
    max-width: 800px;
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 24px;
    z-index: 10;
}

.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 12px;
}

.aws-logo-icon {
    width: 32px;
    height: 32px;
    color: var(--accent-color);
}

h1 {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.highlight {
    color: var(--accent-color);
    background: linear-gradient(to right, #c084fc, #7c3aed);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.progress-stats {
    display: flex;
    align-items: center;
    gap: 20px;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
}

.stat-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.stat-value {
    font-weight: 700;
    font-size: 1.1rem;
}

/* Glass Card */
.glass {
    background: var(--card-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--card-border);
    border-radius: 24px;
    padding: 32px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease;
}

.quiz-card {
    position: relative;
    overflow: hidden;
}

.progress-bar-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: rgba(255, 255, 255, 0.05);
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-color), #c084fc);
    width: 0%;
    transition: width 0.4s ease;
}

/* Quiz Content */
.question-header {
    margin-bottom: 16px;
}

.question-number {
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
    background: rgba(255, 255, 255, 0.05);
    padding: 4px 12px;
    border-radius: 99px;
}

.question-text {
    font-size: 1.5rem;
    line-height: 1.4;
    margin-bottom: 32px;
    font-weight: 600;
}

.options-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
    margin-bottom: 32px;
}

.option-btn {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--card-border);
    padding: 16px 20px;
    border-radius: 12px;
    color: var(--text-secondary);
    text-align: left;
    font-family: inherit;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: flex-start;
    gap: 12px;
}

.option-btn:hover:not(:disabled) {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
    color: var(--text-primary);
}

.option-btn.selected {
    border-color: var(--accent-color);
    background: rgba(124, 58, 237, 0.1);
    color: var(--text-primary);
}

.option-btn.correct {
    border-color: var(--success);
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
}

.option-btn.incorrect {
    border-color: var(--error);
    background: rgba(239, 68, 68, 0.1);
    color: var(--error);
}

.option-letter {
    font-weight: 700;
    opacity: 0.7;
    min-width: 24px;
}

/* Feedback Area */
.feedback-area {
    margin-bottom: 24px;
    padding: 16px;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.03);
    border-left: 4px solid var(--text-secondary);
    animation: slide-up 0.3s ease-out;
}

.feedback-area.correct {
    border-left-color: var(--success);
    background: rgba(16, 185, 129, 0.05);
}

.feedback-area.incorrect {
    border-left-color: var(--error);
    background: rgba(239, 68, 68, 0.05);
}

.feedback-area.hidden {
    display: none;
}

.feedback-text {
    font-weight: 700;
    margin-bottom: 8px;
}

.feedback-explanation {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

/* Controls */
.quiz-controls {
    display: flex;
    align-items: center;
    gap: 16px;
}

.spacer {
    flex: 1;
}

.nav-btn {
    padding: 12px 24px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    border: none;
    transition: all 0.2s;
    font-family: inherit;
}

#reset-btn {
    padding: 8px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.nav-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.secondary {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--card-border);
}

.secondary:hover:not(:disabled) {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
}

.primary {
    background: var(--accent-color);
    color: white;
    box-shadow: 0 4px 12px rgba(124, 58, 237, 0.4);
}

.primary:hover:not(:disabled) {
    background: var(--accent-hover);
    transform: translateY(-1px);
    box-shadow: 0 6px 16px rgba(124, 58, 237, 0.5);
}

.app-footer {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.8rem;
    margin-top: 12px;
}

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

@media (max-width: 600px) {
    .question-text {
        font-size: 1.2rem;
    }
    
    .quiz-card {
        padding: 24px;
    }
}