/* Base design */

:root {
    --bg-charcoal: #0f172a;
    --card-slate: #1e293b;
    --accent-cyan: #06b6d4;  
    --accent-dim: rgba(6, 182, 212, 0.1);
    --text-primary: #f8fafc;
    --text-muted: #94a3b8;
    --border-subtle: #334155;
}

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

body  {
    background-color: var(--bg-charcoal);
    color: var(--text-primary);
    font-family: "Inter", sans-serif;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.app-wrapper {
    width: 100%;
    max-width: 580px;
    padding: 20px;
}

/* Question part */
.quiz-card {
    background-color: var(--card-slate);
    border: 1px solid var(--border-subtle);
    border-radius: 16px;
    padding: 32px;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.3), 0 8px 10px -6px rgba(0, 0, 0, 0.3);
    min-height: 440px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 24px;
}

.brand-badge {
    font-size: 14px;
    font-weight: 700;
    letter-spacing: 0.5px;
    color: var(--text-primary);
}

.counter-text {
    font-size: 13px;
    font-weight: 600;
    color: var(--accent-cyan);
}

.question-title {
    font-size: 20px;
    font-weight: 600;
    line-height: 1.5;
    margin-bottom: 28px;
}

.option-tile {
    background-color: rgba(15, 23, 42, 0.4);
    border: 1px solid var(--border-subtle);
    border-radius: 10px;
    padding: 16px 20px;
    text-align: left;
    color: var(--text-primary);
    font-size: 15px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.option-tile:hover {
    border-color: var(--text-muted);
    background-color: rgba(15, 23, 42, 0.6);
}

.option-tile.selected {
    background-color: var(--accecnt-dim);
    border-color: var(--accent-cyan);
}

/* Navigation bar */
.card-footer {
    margin-top: 32px;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.nav-controls {
    display: flex;
    justify-content: space-between;
}

.action-btn {
    background: transparent;
    border: 1px solid var(--border-subtle);
    border-radius: 8px;
    color: var(--text-primary);
    padding: 10px 18px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
}

.action-btn:hover:not(:disabled) {
    background-color: rgba(255, 255, 255, 0.05);
    border-color: var(--text-muted);
}

.action-btn:disabled {
    opacity: 0.25;
    cursor: not-allowed;
}

/* Progress bar */
.progress-track {
    width: 100%;
    height: 4px;
    background-color: rgba(15, 23, 42, 0.6);
    border-radius: 2px;
    overflow: hidden;
}

.progress-fill {
    width: 0%;
    height: 100%;
    background-color: var(--accent-cyan);
    transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Resut screen */
.result-title { font-size: 26px; color: var(--accent-cyan); font-weight: 700; margin-bottom: 12px; }
.result-desc { color: var(--text-muted); font-size: 15px; line-height: 1.6; margin-bottom: 24px; }
.btn-group { display: flex; gap: 12px; }
.primary-btn { background-color: var(--accent-cyan); color: var(--bg-charcoal); font-weight: 600; border: none; }
.primary-btn:hover { background-color: #22d3ee !important; }