/* ============================================
   Math Blaster - Screen Styles
   Menu, game over, pause, level select,
   level complete, leaderboard, settings screens
   ============================================ */

/* ---------- Screen Overlay Base ---------- */
.screen-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: var(--z-screens);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: rgba(10, 10, 26, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    transition: opacity var(--transition-slow), visibility var(--transition-slow);
    padding: var(--space-lg);
    overflow-y: auto;
}

.screen-overlay.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

/* ---------- Game Title (Main Menu) ---------- */
.game-title {
    font-family: var(--font-display);
    font-size: clamp(28px, 8vw, 56px);
    font-weight: 900;
    background: linear-gradient(135deg, var(--neon-blue), var(--neon-pink), var(--neon-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-align: center;
    margin-bottom: var(--space-xs);
    animation: titleGlow 3s ease infinite;
    line-height: 1.1;
}

@keyframes titleGlow {
    0%, 100% { filter: drop-shadow(0 0 10px rgba(0, 212, 255, 0.5)); }
    50% { filter: drop-shadow(0 0 25px rgba(255, 0, 110, 0.5)); }
}

.game-subtitle {
    font-family: var(--font-display);
    font-size: clamp(10px, 3vw, 14px);
    color: var(--text-muted);
    letter-spacing: 5px;
    text-transform: uppercase;
    margin-bottom: 30px;
    text-align: center;
}

.menu-hint {
    margin-top: 20px;
    font-size: 11px;
    color: var(--text-muted);
    text-align: center;
    opacity: 0.6;
}

/* ---------- Screen Title (Sub-screens) ---------- */
.screen-title {
    font-family: var(--font-display);
    font-size: clamp(20px, 5vw, 36px);
    font-weight: 900;
    color: var(--text-primary);
    text-align: center;
    margin-bottom: var(--space-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
}

.game-over-title {
    background: linear-gradient(135deg, var(--neon-pink), var(--neon-orange));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-size: clamp(22px, 6vw, 40px);
}

.level-complete-title {
    background: linear-gradient(135deg, var(--neon-green), var(--neon-blue));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-size: clamp(22px, 6vw, 40px);
}

/* ---------- Stats Grid ---------- */
.stats-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-md);
    margin: 20px 0;
    width: min(90%, 350px);
}

.stats-grid.compact {
    gap: var(--space-sm);
    margin: var(--space-lg) 0;
}

.stat-card {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: var(--space-md);
    text-align: center;
    transition: border-color var(--transition-normal);
}

.stat-card:hover {
    border-color: var(--border-light);
}

.stat-card .stat-value {
    font-family: var(--font-display);
    font-size: 22px;
    font-weight: 900;
    color: var(--neon-yellow);
    text-shadow: 0 0 10px rgba(255, 190, 11, 0.4);
    line-height: 1.2;
}

.stat-card .stat-label {
    font-size: 10px;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-top: var(--space-xs);
}

/* ---------- New High Score ---------- */
.new-high-score {
    color: var(--neon-yellow);
    font-family: var(--font-display);
    font-size: 14px;
    font-weight: 700;
    margin: 5px 0;
    animation: comboPulse 1s ease infinite;
    text-align: center;
    text-shadow: 0 0 15px rgba(255, 190, 11, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
}

.new-high-score.hidden {
    display: none;
}

/* ---------- Level Complete Stars ---------- */
.level-complete-stars {
    display: flex;
    gap: var(--space-md);
    margin-bottom: var(--space-xl);
    justify-content: center;
}

.level-star {
    width: 48px;
    height: 48px;
    transition: transform var(--transition-normal), opacity var(--transition-normal);
}

.level-star.earned {
    filter: invert(74%) sepia(75%) saturate(600%) hue-rotate(3deg) brightness(105%) contrast(104%);
    animation: starEarn 0.5s ease;
}

.level-star.empty {
    filter: brightness(0) invert(1);
    opacity: 0.15;
}

.level-star:nth-child(1).earned { animation-delay: 0.1s; }
.level-star:nth-child(2).earned { animation-delay: 0.3s; }
.level-star:nth-child(3).earned { animation-delay: 0.5s; }

@keyframes starEarn {
    0% { transform: scale(0) rotate(-180deg); opacity: 0; }
    60% { transform: scale(1.3) rotate(10deg); }
    100% { transform: scale(1) rotate(0deg); opacity: 1; }
}

/* ---------- Level Select Grid ---------- */
.level-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(60px, 1fr));
    gap: var(--space-sm);
    width: min(95%, 500px);
    max-height: 50vh;
    overflow-y: auto;
    padding: var(--space-sm);
    margin-bottom: var(--space-lg);
}

.level-cell {
    width: 100%;
    aspect-ratio: 1;
    border-radius: var(--radius-md);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: 2px solid var(--border-subtle);
    background: rgba(255, 255, 255, 0.03);
    position: relative;
    user-select: none;
    -webkit-user-select: none;
}

.level-cell:hover:not(.locked) {
    border-color: var(--neon-blue);
    background: rgba(0, 212, 255, 0.1);
    transform: scale(1.05);
}

.level-cell:active:not(.locked) {
    transform: scale(0.95);
}

.level-cell .level-number {
    font-family: var(--font-display);
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1;
}

.level-cell .level-stars-mini {
    display: flex;
    gap: 2px;
    margin-top: 3px;
}

.level-cell .level-stars-mini .mini-star {
    width: 8px;
    height: 8px;
}

.level-cell .mini-star.earned {
    filter: invert(74%) sepia(75%) saturate(600%) hue-rotate(3deg) brightness(105%) contrast(104%);
}

.level-cell .mini-star.empty {
    filter: brightness(0) invert(1);
    opacity: 0.2;
}

/* Locked level */
.level-cell.locked {
    opacity: 0.3;
    cursor: not-allowed;
}

.level-cell.locked .level-number {
    display: none;
}

.level-cell .lock-icon {
    width: 18px;
    height: 18px;
    filter: brightness(0) invert(1);
    opacity: 0.4;
}

/* Current level */
.level-cell.current {
    border-color: var(--neon-blue);
    box-shadow: 0 0 12px rgba(0, 212, 255, 0.3);
    animation: levelPulse 2s ease infinite;
}

@keyframes levelPulse {
    0%, 100% { box-shadow: 0 0 12px rgba(0, 212, 255, 0.3); }
    50% { box-shadow: 0 0 20px rgba(0, 212, 255, 0.5); }
}

/* Completed level */
.level-cell.completed {
    border-color: var(--neon-green);
    background: rgba(0, 255, 135, 0.05);
}

/* Boss level */
.level-cell.boss-level {
    border-color: var(--neon-pink);
}

.level-cell.boss-level.current {
    box-shadow: 0 0 12px rgba(255, 0, 110, 0.3);
}

.level-cell .boss-badge {
    position: absolute;
    top: -3px;
    right: -3px;
    width: 14px;
    height: 14px;
    filter: invert(26%) sepia(100%) saturate(6000%) hue-rotate(330deg) brightness(100%) contrast(105%);
}

/* ---------- Leaderboard ---------- */
.leaderboard {
    width: min(90%, 350px);
    max-height: 40vh;
    overflow-y: auto;
    margin-bottom: var(--space-lg);
}

.leaderboard-empty {
    text-align: center;
    color: var(--text-muted);
    padding: 20px;
    font-size: 14px;
}

.lb-entry {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-sm) var(--space-md);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    transition: background var(--transition-fast);
}

.lb-entry:hover {
    background: rgba(255, 255, 255, 0.03);
}

.lb-rank {
    font-family: var(--font-display);
    font-size: 14px;
    font-weight: 700;
    width: 30px;
    flex-shrink: 0;
    color: var(--text-muted);
}

.lb-rank.gold { color: #ffd700; text-shadow: 0 0 8px rgba(255, 215, 0, 0.3); }
.lb-rank.silver { color: #c0c0c0; text-shadow: 0 0 8px rgba(192, 192, 192, 0.3); }
.lb-rank.bronze { color: #cd7f32; text-shadow: 0 0 8px rgba(205, 127, 50, 0.3); }

.lb-info {
    flex: 1;
    margin-left: var(--space-sm);
}

.lb-score {
    font-family: var(--font-display);
    font-size: 16px;
    font-weight: 700;
    color: var(--neon-yellow);
}

.lb-details {
    font-size: 11px;
    color: var(--text-muted);
    margin-top: 2px;
}

/* ---------- Settings Panel ---------- */
.settings-panel {
    width: min(90%, 400px);
    max-height: 55vh;
    overflow-y: auto;
    padding: var(--space-lg);
    margin-bottom: var(--space-lg);
}

.setting-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-md) 0;
    border-bottom: 1px solid var(--border-subtle);
}

.setting-row:last-child {
    border-bottom: none;
}

.setting-label {
    font-size: 14px;
    color: rgba(255, 255, 255, 0.8);
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

/* ---------- Difficulty Selector ---------- */
.difficulty-selector {
    display: flex;
    gap: var(--space-sm);
    margin: 15px 0;
    flex-wrap: wrap;
    justify-content: center;
}

.diff-btn {
    font-family: var(--font-display);
    font-size: 11px;
    padding: var(--space-sm) var(--space-lg);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-light);
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-normal);
    text-transform: uppercase;
    letter-spacing: 1px;
    outline: none;
}

.diff-btn:hover {
    border-color: var(--neon-blue);
    color: var(--neon-blue);
}

.diff-btn:active {
    transform: scale(0.95);
}

.diff-btn.active {
    border-color: var(--neon-blue);
    color: var(--neon-blue);
    background: rgba(0, 212, 255, 0.15);
    box-shadow: 0 0 10px rgba(0, 212, 255, 0.3);
}

/* Difficulty-specific active colors */
.diff-btn[data-diff="easy"].active {
    border-color: var(--neon-green);
    color: var(--neon-green);
    background: rgba(0, 255, 135, 0.15);
    box-shadow: 0 0 10px rgba(0, 255, 135, 0.3);
}

.diff-btn[data-diff="normal"].active {
    border-color: var(--neon-blue);
    color: var(--neon-blue);
    background: rgba(0, 212, 255, 0.15);
    box-shadow: 0 0 10px rgba(0, 212, 255, 0.3);
}

.diff-btn[data-diff="hard"].active {
    border-color: var(--neon-yellow);
    color: var(--neon-yellow);
    background: rgba(255, 190, 11, 0.15);
    box-shadow: 0 0 10px rgba(255, 190, 11, 0.3);
}

.diff-btn[data-diff="insane"].active {
    border-color: var(--neon-pink);
    color: var(--neon-pink);
    background: rgba(255, 0, 110, 0.15);
    box-shadow: 0 0 10px rgba(255, 0, 110, 0.3);
}