:root {
    --bg-dark: #040d1a;
    --aqua-primary: #00d2ff;
    --aqua-secondary: #0072ff;
    --gold-color: #ffd700;
    --danger-color: #ff3b30;
    --glass-bg: rgba(8, 24, 48, 0.75);
    --glass-border: rgba(0, 210, 255, 0.25);
    --text-color: #ffffff;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    user-select: none;
}

body, html {
    width: 100%;
    height: 100%;
    overflow: hidden;
    background-color: var(--bg-dark);
    font-family: 'Outfit', sans-serif;
    color: var(--text-color);
}

#gameContainer {
    position: relative;
    width: 100vw;
    height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Header / Shop Bar */
#hudHeader {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 70px;
    z-index: 10;
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--glass-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 1.5rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
}

.hud-left {
    display: flex;
    align-items: center;
    gap: 1.2rem;
}

.money-badge {
    background: linear-gradient(135deg, #11998e, #38ef7d);
    padding: 0.4rem 1rem;
    border-radius: 30px;
    font-weight: 800;
    font-size: 1.3rem;
    color: #032b13;
    display: flex;
    align-items: center;
    gap: 0.3rem;
    box-shadow: 0 0 15px rgba(56, 239, 125, 0.4);
}

.tank-info {
    display: flex;
    flex-direction: column;
}

.tank-title {
    font-size: 0.75rem;
    letter-spacing: 1px;
    color: var(--aqua-primary);
    font-weight: 800;
}

.egg-tracker {
    display: flex;
    gap: 4px;
    margin-top: 2px;
}

.egg-piece {
    font-size: 1.1rem;
    opacity: 0.3;
    filter: grayscale(1);
    transition: all 0.3s;
}

.egg-piece.unlocked {
    opacity: 1;
    filter: grayscale(0);
    transform: scale(1.1);
}

/* Shop Buttons */
.shop-bar {
    display: flex;
    gap: 0.6rem;
}

.shop-btn {
    background: rgba(13, 40, 75, 0.8);
    border: 1px solid rgba(0, 210, 255, 0.3);
    border-radius: 12px;
    padding: 0.4rem 0.8rem;
    color: #fff;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    transition: all 0.2s ease;
}

.shop-btn:hover:not(:disabled) {
    background: rgba(0, 114, 255, 0.6);
    border-color: var(--aqua-primary);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 210, 255, 0.3);
}

.shop-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    filter: grayscale(0.8);
}

.shop-btn.maxed {
    background: rgba(46, 204, 113, 0.2);
    border-color: #2ecc71;
}

.shop-btn .btn-icon {
    font-size: 1.4rem;
}

.shop-btn .btn-text {
    display: flex;
    flex-direction: column;
    text-align: left;
}

.shop-btn .btn-label {
    font-size: 0.75rem;
    color: #a0c4ff;
    font-weight: 600;
}

.shop-btn .btn-cost {
    font-size: 0.85rem;
    font-weight: 800;
    color: var(--gold-color);
}

.egg-btn {
    background: linear-gradient(135deg, rgba(255, 215, 0, 0.2), rgba(255, 140, 0, 0.2));
    border-color: var(--gold-color);
}

.hud-right {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.icon-btn {
    background: rgba(13, 40, 75, 0.8);
    border: 1px solid var(--glass-border);
    border-radius: 50%;
    width: 42px;
    height: 42px;
    font-size: 1.2rem;
    color: #fff;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
}

.icon-btn:hover {
    background: var(--aqua-secondary);
}

/* Canvas */
#gameCanvas {
    width: 100%;
    height: 100%;
    display: block;
    cursor: crosshair;
}

/* Alien Warning Banner */
.alien-warning-overlay {
    position: absolute;
    top: 90px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 20;
    pointer-events: none;
}

.alien-warning-overlay.hidden {
    display: none;
}

.warning-box {
    background: rgba(255, 59, 48, 0.85);
    backdrop-filter: blur(8px);
    border: 2px solid #ff9500;
    border-radius: 16px;
    padding: 0.8rem 2rem;
    text-align: center;
    animation: pulseWarning 1s infinite alternate;
    box-shadow: 0 0 30px rgba(255, 59, 48, 0.8);
}

@keyframes pulseWarning {
    from { transform: scale(1); }
    to { transform: scale(1.05); }
}

.warning-box h2 {
    font-size: 1.5rem;
    font-weight: 900;
    color: #ffffff;
    letter-spacing: 2px;
}

.warning-box p {
    font-size: 0.9rem;
    color: #ffebd8;
}

/* Modal Overlay */
.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(2, 10, 22, 0.85);
    backdrop-filter: blur(16px);
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-overlay.hidden {
    display: none;
}

.modal-content {
    background: linear-gradient(145deg, #09203f, #537895);
    border: 2px solid var(--aqua-primary);
    border-radius: 24px;
    padding: 2.5rem;
    max-width: 500px;
    width: 90%;
    text-align: center;
    box-shadow: 0 10px 40px rgba(0, 210, 255, 0.3);
}

.modal-content h1 {
    font-size: 2.2rem;
    font-weight: 900;
    margin-bottom: 0.5rem;
    background: linear-gradient(to right, #00d2ff, #38ef7d);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.modal-content p {
    font-size: 1rem;
    color: #d0e6ff;
    margin-bottom: 1.5rem;
    line-height: 1.4;
}

.modal-features {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
    margin-bottom: 2rem;
    text-align: left;
    background: rgba(0, 0, 0, 0.25);
    padding: 1rem 1.2rem;
    border-radius: 16px;
}

.feature-item {
    font-size: 0.95rem;
    display: flex;
    align-items: center;
    gap: 0.8rem;
    color: #e0f2fe;
}

.primary-btn {
    background: linear-gradient(135deg, #00c6ff, #0072ff);
    color: #fff;
    border: none;
    padding: 1rem 2.5rem;
    font-size: 1.2rem;
    font-weight: 800;
    border-radius: 40px;
    cursor: pointer;
    letter-spacing: 1px;
    box-shadow: 0 6px 20px rgba(0, 114, 255, 0.5);
    transition: all 0.3s ease;
}

.primary-btn:hover {
    transform: translateY(-3px) scale(1.03);
    box-shadow: 0 10px 30px rgba(0, 210, 255, 0.7);
}