:root {
    --primary-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --secondary-gradient: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --success-gradient: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --warning-gradient: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
    --danger-gradient: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
    --dark-gradient: linear-gradient(135deg, #232526 0%, #414345 100%);
}

body {
    background: linear-gradient(45deg, #0c0c0c, #1a1a2e, #16213e, #0f3460);
    color: #fff;
    overflow-x: hidden;
}

.navbar-custom {
    top: 1rem;
    width: 10%;
    right: 1rem;
    border-radius: 2rem;
    backdrop-filter: blur(20px);
    z-index: 100;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.logo-container {
    position: relative;
    display: inline-block;
}

.logo-glow {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    /*box-shadow: 0 0 30px rgba(79, 172, 254, 0.6);*/
}
.stats-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 15px 25px;
    text-align: center;
    transition: all 0.3s ease;
}

.stats-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.3);
}

/* Question Card Styles */
.question-container {
    position: relative;
    z-index: 10;
}

.question-card {
    background: linear-gradient(145deg, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.05));
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 30px;
    padding: 40px;
    margin-bottom: 30px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    transition: all 0.5s ease;
    animation: slideInUp 0.8s ease;
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(50px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.question-number {
    width: 80px;
    height: 80px;
    background: var(--secondary-gradient);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    font-weight: 700;
    box-shadow: 0 10px 30px rgba(245, 87, 108, 0.4);
}

.option-card {
    background: linear-gradient(145deg, rgba(255, 255, 255, 0.08), rgba(255, 255, 255, 0.03));
    backdrop-filter: blur(15px);
    border: 2px solid rgba(255, 255, 255, 0.1);
    border-radius: 25px;
    padding: 25px;
    margin-bottom: 20px;
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    position: relative;
    overflow: hidden;
}

.option-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s;
}

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

.option-card:hover {
    transform: scale(1.03);
    border-color: #4facfe;
    box-shadow: 0 15px 40px rgba(79, 172, 254, 0.3);
}

.option-card.loading {
    border: 4px solid #007bff;
    animation: rotate-border 1s linear infinite;
}

@keyframes rotate-border {
    0% { border-color: #007bff; }
    25% { border-color: #00ffc3; }
    50% { border-color: #ff9800; }
    75% { border-color: #ff0055; }
    100% { border-color: #007bff; }
}

.option-selected {
    background: var(--success-gradient) !important;
    border-color: #00f2fe !important;
    transform: scale(1.05) !important;
    box-shadow: 0 20px 50px rgba(0, 242, 254, 0.4) !important;
}

.option-letter {
    width: 50px;
    height: 50px;
    background: var(--warning-gradient);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 18px;
    color: #000;
    margin-left: 20px;
    transition: all 0.3s ease;
}

.option-selected .option-letter {
    background: rgba(255, 255, 255, 0.3);
    color: #fff;
    animation: bounce 0.6s ease;
}

@keyframes bounce {

    0%,
    20%,
    60%,
    100% {
        transform: translateY(0);
    }

    40% {
        transform: translateY(-10px);
    }

    80% {
        transform: translateY(-5px);
    }
}

/* Progress Bar */
.progress-container {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50px;
    padding: 8px;
    margin-bottom: 40px;
    backdrop-filter: blur(10px);
}

.progress-bar-custom {
    background: var(--success-gradient);
    height: 20px;
    border-radius: 50px;
    transition: width 0.8s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    position: relative;
    overflow: hidden;
}

.progress-bar-custom::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% {
        transform: translateX(-100%);
    }

    100% {
        transform: translateX(100%);
    }
}

/* Buttons */
.btn-custom {
    padding: 15px 35px;
    border-radius: 25px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    border: none;
    position: relative;
    overflow: hidden;
    transition: all 0.3s ease;
}

.btn-primary-custom {
    background: var(--primary-gradient);
    color: white;
}

.btn-success-custom {
    background: var(--success-gradient);
    color: white;
}

.btn-warning-custom {
    background: var(--warning-gradient);
    color: #000;
}

.btn-custom:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
}

.btn-custom::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.5s;
}

.btn-custom:hover::before {
    left: 100%;
}

/* Footer */
.footer-custom {
    background: var(--dark-gradient);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    margin-top: 80px;
}

.social-icon {
    width: 50px;
    height: 50px;
    background: var(--primary-gradient);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 5px;
    transition: all 0.3s ease;
    text-decoration: none;
    color: white;
}

.social-icon:hover {
    transform: translateY(-5px) rotate(360deg);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.4);
    color: white;
}

/* Questions Sidebar */
.questions-sidebar {
    background: linear-gradient(145deg, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.05));
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 30px;
    padding: 30px;
    height: fit-content;
    position: sticky;
    top: 140px;
}

.question-nav-item {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 10px;
    cursor: pointer;
    transition: all 0.3s ease;
    background: rgba(255, 255, 255, 0.1);
    border: 2px solid rgba(255, 255, 255, 0.2);
    font-weight: 600;
    color: #fff;
}

.question-nav-item:hover {
    transform: scale(1.1);
    background: var(--primary-gradient);
    border-color: #667eea;
}

.question-nav-item.current {
    background: var(--secondary-gradient);
    border-color: #f5576c;
    transform: scale(1.2);
}

.question-nav-item.answered {
    background: var(--success-gradient);
    border-color: #00f2fe;
}

.question-nav-item.answered::after {
    content: '✓';
    position: absolute;
    font-size: 12px;
    color: #fff;
}

@media (max-width: 768px) {
    .question-card {
        padding: 25px;
        margin-bottom: 20px;
    }

    .option-card {
        padding: 20px;
    }

    .question-number {
        width: 60px;
        height: 60px;
        font-size: 20px;
    }

    .btn-custom {
        padding: 12px 25px;
        font-size: 14px;
    }

    .questions-sidebar {
        position: relative;
        top: 0;
        margin-bottom: 30px;
    }

    .question-nav-item {
        width: 40px;
        height: 40px;
        margin: 5px;
        font-size: 14px;
    }
}

/* Timer Animation */
.timer-warning {
    animation: timerPulse 1s ease-in-out infinite;
}

@keyframes timerPulse {

    0%,
    100% {
        color: #fff;
    }

    50% {
        color: #ff6b6b;
    }
}

/* 3D Effects */
.card-3d {
    transform-style: preserve-3d;
    transition: transform 0.3s ease;
}

.card-3d:hover {
    transform: rotateY(5deg) rotateX(5deg);
}