@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); }
}

.btn:active {
    animation: pulse 0.2s ease-in-out;
}

@keyframes shimmer {
    0% { background-position: -468px 0; }
    100% { background-position: 468px 0; }
}

.loading-shimmer {
    background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
    background-size: 400% 100%;
    animation: shimmer 1.2s ease-in-out infinite;
}

@keyframes typewriter {
    from { width: 0; }
    to { width: 100%; }
}

.typewriter {
    overflow: hidden;
    border-right: 2px solid #667eea;
    white-space: nowrap;
    animation: typewriter 2s steps(40, end);
}

@keyframes bounceIn {
    0% {
        opacity: 0;
        transform: scale(0.3);
    }
    50% {
        opacity: 1;
        transform: scale(1.05);
    }
    70% {
        transform: scale(0.9);
    }
    100% {
        opacity: 1;
        transform: scale(1);
    }
}

.bounce-in {
    animation: bounceIn 0.6s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.stat-card {
    animation: fadeInUp 0.3s ease-out;
}

.stat-card:nth-child(2) { animation-delay: 0.05s; }
.stat-card:nth-child(3) { animation-delay: 0.1s; }

.glow {
    box-shadow: 0 0 20px rgba(102, 126, 234, 0.6);
}

.btn-primary:hover {
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.ripple {
    position: relative;
    overflow: hidden;
}

.ripple::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.ripple:active::after {
    width: 300px;
    height: 300px;
}

@keyframes slideInFromRight {
    from {
        opacity: 0;
        transform: translateX(100%);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.new-question {
    animation: slideInFromRight 0.5s ease-out;
}


@keyframes confetti {
    0% { transform: translateY(0) rotateZ(0deg); opacity: 1; }
    100% { transform: translateY(-1000px) rotateZ(720deg); opacity: 0; }
}

.confetti {
    position: fixed;
    width: 10px;
    height: 10px;
    background: #667eea;
    animation: confetti 3s linear infinite;
}


@keyframes progressFill {
    from { width: 0%; }
    to { width: var(--progress-width); }
}

.progress-fill {
    animation: progressFill 1s ease-out;
}

.question-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transition: left 0.5s;
}

.question-card:hover::before {
    left: 100%;
}


@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.spinner {
    border: 2px solid #f3f3f3;
    border-top: 2px solid #667eea;
    border-radius: 50%;
    width: 20px;
    height: 20px;
    animation: spin 1s linear infinite;
}

@keyframes checkmark {
    0% {
        height: 0;
        width: 0;
        opacity: 1;
    }
    20% {
        height: 0;
        width: 6px;
        opacity: 1;
    }
    40% {
        height: 12px;
        width: 6px;
        opacity: 1;
    }
    100% {
        height: 12px;
        width: 6px;
        opacity: 1;
    }
}

.checkmark {
    width: 6px;
    height: 12px;
    border: solid #10b981;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
    animation: checkmark 0.6s ease-in-out;
}

.particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: -1;
}

.particle {
    position: absolute;
    width: 4px;
    height: 4px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    animation: float 6s ease-in-out infinite;
}


.gradient-text {
    background: linear-gradient(45deg, #667eea, #764ba2);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}


.glass {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.2);
}


@media (prefers-color-scheme: dark) {
    .neon {
        color: #fff;
        text-shadow: 
            0 0 5px #667eea,
            0 0 10px #667eea,
            0 0 15px #667eea,
            0 0 20px #667eea;
    }
}

::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb {
    background: rgba(102, 126, 234, 0.6);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(102, 126, 234, 0.8);
}

.btn:focus,
.nav-btn:focus,
.dot:focus {
    outline: 2px solid #667eea;
    outline-offset: 2px;
}

@media (prefers-contrast: high) {
    .question-card {
        border: 2px solid #000;
    }
    
    .btn {
        border: 2px solid currentColor;
    }
}

@media (prefers-reduced-motion: reduce) {
    .question-card {
        animation: none;
    }
    
    .stat-card {
        animation: none;
    }
    
    * {
        transition-duration: 0.01ms !important;
        animation-duration: 0.01ms !important;
    }
}