/* ============================================================
   airbus.css — Airbus-themed visual overlay (loaded after style.css)
   Tightens palette to Airbus signal blue, adds A320 silhouette
   hero, bank selector chips, and subtle aviation flourishes.
   ============================================================ */

:root {
    --airbus-blue: #00205B;        /* Airbus heritage navy */
    --airbus-signal: #1E64C8;      /* Modern Airbus blue */
    --airbus-cyan: #00B5E2;        /* PFD accent cyan */
    --airbus-amber: #ffb300;       /* ECAM caution amber */
}

/* Soft gradient sky in light mode, dark cockpit in dark mode */
body {
    background:
        radial-gradient(ellipse at top, rgba(30,100,200,0.06), transparent 60%),
        radial-gradient(ellipse at bottom right, rgba(0,181,226,0.04), transparent 50%),
        var(--bg);
    background-attachment: fixed;
}

[data-theme="dark"] body {
    background:
        radial-gradient(ellipse at top, rgba(0,30,90,0.45), transparent 60%),
        radial-gradient(ellipse at bottom right, rgba(0,181,226,0.05), transparent 50%),
        var(--bg);
}

/* --- Hero: A320 cockpit-night photo with overlaid title --- */
.hero-photo {
    position: relative;
    width: 100%;
    aspect-ratio: 16 / 7;
    max-height: 260px;
    overflow: hidden;
    border-radius: 14px;
    margin: 4px 0 10px;
    background: #000;
    box-shadow: 0 6px 24px rgba(0,32,91,0.25);
}

.hero-photo img {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    /* The image is 480x406 — push the eye toward the PFDs and centre pedestal */
    object-position: center 35%;
    filter: saturate(1.1) contrast(1.05);
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background:
        linear-gradient(180deg,
            rgba(0,16,40,0.15) 0%,
            rgba(0,16,40,0.45) 55%,
            rgba(0,32,91,0.85) 100%),
        linear-gradient(135deg,
            rgba(30,100,200,0.10) 0%,
            rgba(0,181,226,0.05) 50%,
            transparent 100%);
}

.hero-text {
    position: absolute;
    left: 0;
    right: 0;
    bottom: 14px;
    padding: 0 18px;
    text-align: center;
    color: #fff;
}

.hero-text h1 {
    margin: 0;
    font-weight: 800;
    letter-spacing: -0.5px;
    font-size: clamp(1.4rem, 4vw, 2.1rem);
    color: #fff;
    text-shadow: 0 2px 12px rgba(0,0,0,0.6);
}

.hero-accent {
    font-weight: 600;
    color: var(--airbus-cyan);
    text-transform: uppercase;
    letter-spacing: 3px;
    font-size: 0.7em;
    margin-left: 6px;
    text-shadow: 0 0 14px rgba(0,181,226,0.6);
}

.hero-credit {
    position: absolute;
    right: 8px;
    bottom: 6px;
    font-size: 0.6rem;
    color: rgba(255,255,255,0.55);
    text-decoration: none;
    background: rgba(0,0,0,0.35);
    padding: 2px 6px;
    border-radius: 4px;
    letter-spacing: 0.3px;
}

.hero-credit:hover {
    color: #fff;
    background: rgba(0,0,0,0.6);
}

/* Bank label + question count line under the hero */
.hero-subtitle {
    display: flex;
    align-items: center;
    gap: 10px;
    justify-content: center;
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 18px;
}

.hero-pill {
    display: inline-flex;
    align-items: center;
    padding: 3px 10px;
    border-radius: 999px;
    background: rgba(30,100,200,0.12);
    color: var(--airbus-signal);
    border: 1px solid rgba(30,100,200,0.28);
    font-weight: 700;
    font-size: 0.7rem;
    letter-spacing: 0.5px;
    text-transform: uppercase;
}

[data-theme="dark"] .hero-pill {
    background: rgba(0,181,226,0.12);
    color: var(--airbus-cyan);
    border-color: rgba(0,181,226,0.4);
}

/* --- Top bar with bank selector --- */
.top-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 4px;
    margin-bottom: 4px;
    gap: 12px;
    flex-wrap: wrap;
}

.bank-selector {
    display: inline-flex;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 999px;
    padding: 3px;
    gap: 2px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.06);
}

.bank-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    border: 0;
    background: transparent;
    color: var(--text-muted);
    font-size: 0.78rem;
    font-weight: 600;
    border-radius: 999px;
    cursor: pointer;
    transition: background 0.15s, color 0.15s;
    white-space: nowrap;
}

.bank-btn:hover {
    color: var(--text);
}

.bank-btn.active {
    background: var(--airbus-signal);
    color: #fff;
    box-shadow: 0 2px 8px rgba(30,100,200,0.35);
}

[data-theme="dark"] .bank-btn.active {
    background: var(--airbus-cyan);
    color: #001a2e;
    box-shadow: 0 2px 12px rgba(0,181,226,0.35);
}

.bank-count {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 22px;
    padding: 0 6px;
    height: 16px;
    border-radius: 8px;
    background: rgba(0,0,0,0.08);
    font-size: 0.65rem;
    font-weight: 700;
}

.bank-btn.active .bank-count {
    background: rgba(255,255,255,0.22);
}

/* --- Primary button picks up Airbus blue --- */
.btn-primary {
    background: linear-gradient(135deg, var(--airbus-signal), var(--airbus-blue));
    border-color: var(--airbus-blue);
    color: #fff;
}

.btn-primary:hover {
    filter: brightness(1.1);
    box-shadow: 0 4px 16px rgba(30,100,200,0.35);
}

[data-theme="dark"] .btn-primary {
    background: linear-gradient(135deg, var(--airbus-cyan), var(--airbus-signal));
}

/* --- Mode tile active glow --- */
.mode-btn.active {
    border-color: var(--airbus-signal);
    background: linear-gradient(180deg, rgba(30,100,200,0.06), transparent);
    box-shadow: inset 0 0 0 1px var(--airbus-signal), 0 4px 14px rgba(30,100,200,0.15);
}

[data-theme="dark"] .mode-btn.active {
    border-color: var(--airbus-cyan);
    background: linear-gradient(180deg, rgba(0,181,226,0.08), transparent);
    box-shadow: inset 0 0 0 1px var(--airbus-cyan), 0 4px 18px rgba(0,181,226,0.18);
}

/* --- Stats cards lift on hover --- */
.stat-item {
    transition: transform 0.15s, box-shadow 0.15s;
}
.stat-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 18px rgba(30,100,200,0.12);
}
.stat-value {
    background: linear-gradient(135deg, var(--airbus-signal), var(--airbus-blue));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}
[data-theme="dark"] .stat-value {
    background: linear-gradient(135deg, var(--airbus-cyan), #6cd8ff);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

/* --- Subject chip left border in subject color (already inline) ---
   Add a subtle ATA-chapter shoulder stripe to each subject row.        */
.subject-item {
    border-left: 3px solid transparent;
    transition: border-color 0.15s, background 0.15s;
}
.subject-item.selected {
    border-left-color: var(--airbus-signal);
}
[data-theme="dark"] .subject-item.selected {
    border-left-color: var(--airbus-cyan);
}

/* --- Progress bar in Airbus blue --- */
.progress-fill {
    background: linear-gradient(90deg, var(--airbus-cyan), var(--airbus-signal));
}

/* --- Subject groups (accordion) --- */
.subject-groups {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 16px;
}

.subject-group {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: border-color 0.15s, box-shadow 0.15s;
}

.subject-group[open] {
    border-color: var(--airbus-signal);
    box-shadow: 0 2px 10px rgba(30,100,200,0.08);
}

[data-theme="dark"] .subject-group[open] {
    border-color: var(--airbus-cyan);
    box-shadow: 0 2px 14px rgba(0,181,226,0.12);
}

/* Hide default disclosure marker */
.subject-group summary { list-style: none; cursor: pointer; }
.subject-group summary::-webkit-details-marker { display: none; }
.subject-group summary::marker { content: ''; }

.subject-group-summary {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 14px;
    font-weight: 600;
    user-select: none;
}

.subject-group-summary:hover {
    background: rgba(30,100,200,0.04);
}

[data-theme="dark"] .subject-group-summary:hover {
    background: rgba(0,181,226,0.06);
}

.group-chevron {
    display: inline-block;
    color: var(--airbus-signal);
    transition: transform 0.18s ease;
    font-size: 0.7rem;
    width: 12px;
    text-align: center;
}

[data-theme="dark"] .group-chevron { color: var(--airbus-cyan); }

.subject-group[open] .group-chevron {
    transform: rotate(90deg);
}

.group-check-label {
    display: inline-flex;
    align-items: center;
    margin: 0;
    cursor: pointer;
}

.group-check {
    margin: 0;
    width: 16px;
    height: 16px;
    cursor: pointer;
    accent-color: var(--airbus-signal);
}

[data-theme="dark"] .group-check { accent-color: var(--airbus-cyan); }

.group-name {
    flex: 1;
    font-size: 0.95rem;
    color: var(--text);
}

.group-meta {
    font-size: 0.7rem;
    color: var(--text-muted);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.group-count {
    background: rgba(30,100,200,0.12);
    color: var(--airbus-signal);
    padding: 2px 10px;
    border-radius: 999px;
    font-size: 0.75rem;
    font-weight: 700;
    min-width: 36px;
    text-align: center;
}

[data-theme="dark"] .group-count {
    background: rgba(0,181,226,0.16);
    color: var(--airbus-cyan);
}

.subject-group .subject-grid {
    padding: 4px 12px 12px;
    gap: 6px;
    border-top: 1px solid var(--border);
    background: linear-gradient(180deg, rgba(30,100,200,0.025), transparent);
}

[data-theme="dark"] .subject-group .subject-grid {
    background: linear-gradient(180deg, rgba(0,181,226,0.04), transparent);
}

/* Slight indent + smaller font for sub-items inside groups */
.subject-group .subject-item {
    margin-left: 12px;
    font-size: 0.92rem;
}

/* --- Explanation box (shown after answer reveal) --- */
.explanation-box {
    margin: 12px 0;
    padding: 12px 14px;
    background: linear-gradient(135deg, rgba(0,181,226,0.07), rgba(30,100,200,0.05));
    border-left: 3px solid var(--airbus-signal);
    border-radius: var(--radius);
    font-size: 0.88rem;
    line-height: 1.5;
    color: var(--text);
}

.explanation-box strong {
    color: var(--airbus-signal);
    text-transform: uppercase;
    font-size: 0.72rem;
    letter-spacing: 0.6px;
    display: block;
    margin-bottom: 4px;
}

[data-theme="dark"] .explanation-box {
    background: linear-gradient(135deg, rgba(0,181,226,0.1), rgba(30,100,200,0.06));
    border-left-color: var(--airbus-cyan);
}

[data-theme="dark"] .explanation-box strong {
    color: var(--airbus-cyan);
}