/* ===========================
   CSS Variables & Reset
   =========================== */
:root {
    --bg-primary: #0a0a1a;
    --bg-secondary: #12122a;
    --bg-card: rgba(20, 20, 50, 0.7);
    --neon-green: #00ff88;
    --neon-green-dim: #00cc6a;
    --neon-cyan: #00e5ff;
    --neon-pink: #ff2d75;
    --neon-purple: #b24dff;
    --neon-yellow: #ffe600;
    --text-primary: #e8e8f0;
    --text-secondary: #8888aa;
    --border-color: rgba(0, 255, 136, 0.15);
    --shadow-neon: 0 0 20px rgba(0, 255, 136, 0.3);
    --shadow-neon-strong: 0 0 40px rgba(0, 255, 136, 0.5);
    --font-display: 'Orbitron', sans-serif;
    --font-body: 'Inter', sans-serif;
    --canvas-size: 400px;
}

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

html {
    font-size: 16px;
}

body {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-primary);
    color: var(--text-primary);
    font-family: var(--font-body);
    overflow: hidden;
    position: relative;
}

/* ===========================
   Background Glows
   =========================== */
.bg-glow {
    position: fixed;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.4;
    pointer-events: none;
    z-index: 0;
    animation: glowFloat 12s ease-in-out infinite alternate;
}

.bg-glow-1 {
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, var(--neon-purple), transparent 70%);
    top: -150px;
    left: -100px;
}

.bg-glow-2 {
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, var(--neon-green), transparent 70%);
    bottom: -100px;
    right: -80px;
    animation-delay: -4s;
}

.bg-glow-3 {
    width: 350px;
    height: 350px;
    background: radial-gradient(circle, var(--neon-cyan), transparent 70%);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation-delay: -8s;
    opacity: 0.2;
}

@keyframes glowFloat {
    0% { transform: translate(0, 0) scale(1); }
    50% { transform: translate(30px, -20px) scale(1.1); }
    100% { transform: translate(-20px, 30px) scale(0.95); }
}

/* ===========================
   Container
   =========================== */
.container {
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    padding: 20px;
}

/* ===========================
   Header / Title
   =========================== */
header {
    text-align: center;
}

.title {
    font-family: var(--font-display);
    font-size: 2.5rem;
    font-weight: 900;
    letter-spacing: 6px;
    display: flex;
    align-items: center;
    gap: 12px;
    text-shadow: 0 0 20px rgba(0, 255, 136, 0.5), 0 0 60px rgba(0, 255, 136, 0.2);
    animation: titlePulse 3s ease-in-out infinite;
}

.title-icon {
    font-size: 2.8rem;
    filter: drop-shadow(0 0 10px rgba(0, 255, 136, 0.6));
    animation: iconBounce 2s ease-in-out infinite;
}

.title-accent {
    color: var(--neon-green);
}

@keyframes titlePulse {
    0%, 100% { text-shadow: 0 0 20px rgba(0, 255, 136, 0.5), 0 0 60px rgba(0, 255, 136, 0.2); }
    50% { text-shadow: 0 0 30px rgba(0, 255, 136, 0.7), 0 0 80px rgba(0, 255, 136, 0.3); }
}

@keyframes iconBounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-5px); }
}

/* ===========================
   Game Wrapper
   =========================== */
.game-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

/* ===========================
   Scoreboard
   =========================== */
.scoreboard {
    display: flex;
    gap: 16px;
    width: 100%;
    max-width: var(--canvas-size);
}

.score-card {
    flex: 1;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 12px 8px;
    text-align: center;
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.score-card:hover {
    border-color: rgba(0, 255, 136, 0.4);
    box-shadow: var(--shadow-neon);
}

.score-label {
    font-family: var(--font-display);
    font-size: 0.6rem;
    letter-spacing: 3px;
    color: var(--text-secondary);
    margin-bottom: 4px;
}

.score-value {
    font-family: var(--font-display);
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--neon-green);
    text-shadow: 0 0 10px rgba(0, 255, 136, 0.5);
}

.high-score-card .score-value {
    color: var(--neon-yellow);
    text-shadow: 0 0 10px rgba(255, 230, 0, 0.5);
}

.score-card.score-pop {
    animation: scorePop 0.3s ease;
}

@keyframes scorePop {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); border-color: var(--neon-green); box-shadow: var(--shadow-neon-strong); }
    100% { transform: scale(1); }
}

/* ===========================
   Canvas Container
   =========================== */
.canvas-container {
    position: relative;
    width: var(--canvas-size);
    height: var(--canvas-size);
    border-radius: 16px;
    overflow: hidden;
    border: 2px solid var(--border-color);
    box-shadow: var(--shadow-neon), inset 0 0 60px rgba(0, 0, 0, 0.5);
    background: var(--bg-secondary);
}

#gameCanvas {
    display: block;
    width: 100%;
    height: 100%;
    border-radius: 14px;
}

/* ===========================
   Overlays
   =========================== */
.overlay {
    position: absolute;
    inset: 0;
    background: rgba(5, 5, 20, 0.92);
    backdrop-filter: blur(8px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10;
    animation: overlayFadeIn 0.4s ease;
}

.overlay.hidden {
    display: none;
}

@keyframes overlayFadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.overlay-content {
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 14px;
}

.overlay-icon {
    font-size: 4rem;
    animation: iconBounce 2s ease-in-out infinite;
}

.overlay-content h2 {
    font-family: var(--font-display);
    font-size: 2rem;
    letter-spacing: 6px;
    color: var(--neon-green);
    text-shadow: 0 0 20px rgba(0, 255, 136, 0.5);
}

.overlay-content p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.6;
}

kbd {
    display: inline-block;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 6px;
    padding: 3px 8px;
    font-family: var(--font-display);
    font-size: 0.7rem;
    color: var(--neon-cyan);
    margin: 0 2px;
}

.final-score {
    font-family: var(--font-display);
    font-size: 1.2rem;
    color: var(--text-primary) !important;
}

.final-score span {
    color: var(--neon-green);
    font-weight: 700;
}

.new-high {
    font-family: var(--font-display);
    font-size: 0.9rem;
    color: var(--neon-yellow) !important;
    animation: newHighPulse 0.8s ease-in-out infinite alternate;
}

@keyframes newHighPulse {
    from { transform: scale(1); text-shadow: 0 0 10px rgba(255, 230, 0, 0.3); }
    to { transform: scale(1.05); text-shadow: 0 0 30px rgba(255, 230, 0, 0.7); }
}

/* ===========================
   Buttons
   =========================== */
.btn {
    position: relative;
    font-family: var(--font-display);
    font-size: 0.85rem;
    letter-spacing: 4px;
    padding: 14px 40px;
    border: 2px solid var(--neon-green);
    background: transparent;
    color: var(--neon-green);
    border-radius: 50px;
    cursor: pointer;
    overflow: hidden;
    transition: all 0.3s ease;
    margin-top: 6px;
}

.btn:hover {
    background: var(--neon-green);
    color: var(--bg-primary);
    box-shadow: var(--shadow-neon-strong);
    transform: translateY(-2px);
}

.btn:active {
    transform: translateY(0);
}

.btn-glow {
    position: absolute;
    inset: -2px;
    border-radius: 50px;
    background: linear-gradient(45deg, var(--neon-green), var(--neon-cyan), var(--neon-purple), var(--neon-green));
    background-size: 400% 400%;
    z-index: -1;
    opacity: 0;
    filter: blur(12px);
    transition: opacity 0.3s ease;
    animation: glowRotate 3s linear infinite;
}

.btn:hover .btn-glow {
    opacity: 0.7;
}

@keyframes glowRotate {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

/* ===========================
   Difficulty Selector
   =========================== */
.difficulty-selector {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-top: 8px;
}

.diff-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    letter-spacing: 1px;
    font-family: var(--font-display);
}

.diff-btn {
    font-family: var(--font-display);
    font-size: 0.65rem;
    letter-spacing: 2px;
    padding: 6px 14px;
    border: 1px solid rgba(255, 255, 255, 0.15);
    background: transparent;
    color: var(--text-secondary);
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
}

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

.diff-btn.active {
    border-color: var(--neon-green);
    color: var(--neon-green);
    background: rgba(0, 255, 136, 0.1);
    box-shadow: 0 0 10px rgba(0, 255, 136, 0.2);
}

/* ===========================
   Mobile Controls
   =========================== */
.mobile-controls {
    display: none;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    margin-top: 10px;
}

.control-row {
    display: flex;
    gap: 6px;
}

.control-btn {
    width: 60px;
    height: 60px;
    font-size: 1.4rem;
    border: 2px solid var(--border-color);
    background: var(--bg-card);
    color: var(--neon-green);
    border-radius: 14px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(10px);
    transition: all 0.15s ease;
    -webkit-tap-highlight-color: transparent;
    user-select: none;
}

.control-btn:active {
    background: rgba(0, 255, 136, 0.15);
    border-color: var(--neon-green);
    box-shadow: var(--shadow-neon);
    transform: scale(0.92);
}

/* ===========================
   Footer
   =========================== */
footer {
    text-align: center;
    max-width: var(--canvas-size);
}

footer p {
    font-size: 0.75rem;
    color: var(--text-secondary);
    letter-spacing: 0.5px;
    line-height: 1.6;
}

/* ===========================
   Responsive Design
   =========================== */
@media (max-width: 480px) {
    :root {
        --canvas-size: 320px;
    }

    .title {
        font-size: 1.5rem;
        letter-spacing: 3px;
        gap: 8px;
    }

    .title-icon {
        font-size: 1.8rem;
    }

    .score-value {
        font-size: 1.2rem;
    }

    .mobile-controls {
        display: flex;
    }

    body {
        overflow: auto;
    }

    .bg-glow {
        display: none;
    }

    .overlay-icon {
        font-size: 3rem;
    }

    .overlay-content h2 {
        font-size: 1.4rem;
    }
}

@media (min-width: 481px) and (max-width: 768px) {
    :root {
        --canvas-size: 380px;
    }

    .title {
        font-size: 2rem;
    }
}

/* ===========================
   Touch / Hover Media
   =========================== */
@media (hover: none) and (pointer: coarse) {
    .mobile-controls {
        display: flex;
    }
}

/* ===========================
   Selection Styling
   =========================== */
::selection {
    background: rgba(0, 255, 136, 0.3);
    color: var(--text-primary);
}

/* ===========================
   Scrollbar Styling
   =========================== */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: rgba(0, 255, 136, 0.3);
    border-radius: 3px;
}