body {
    margin: 0;
    padding: 0;
    overflow: hidden;
    background-color: #87CEEB;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    user-select: none;
    cursor: crosshair;
}

#canvas-container {
    width: 100vw;
    height: 100vh;
    display: block;
}

#ui {
    position: absolute;
    top: 20px;
    left: 20px;
    color: #333;
    background: rgba(255, 255, 255, 0.85);
    padding: 15px 20px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    pointer-events: none;
    z-index: 10;
}

h1 { margin: 0 0 5px 0; font-size: 1.4rem; color: #1a1a1a; }
p { margin: 0; font-size: 0.9rem; color: #555; }

.instruction { 
    margin-top: 10px; 
    font-size: 0.85rem; 
    color: #BC2020; 
    font-weight: bold; 
    line-height: 1.4; 
}

#flight-data { 
    margin-top: 8px; 
    font-size: 1.1rem; 
    color: #1a1a1a; 
    font-weight: bold; 
    line-height: 1.5; 
}

#score-board { 
    margin-top: 5px; 
    font-size: 1.1rem; 
    color: #1a476f; 
    font-weight: bold; 
}

@keyframes blink { 0% { opacity: 1; } 50% { opacity: 0; } 100% { opacity: 1; } }
#stall-warning { color: #BC2020; display: none; animation: blink 0.5s infinite; }

#crosshair {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: rgba(255, 255, 255, 0.6);
    font-size: 24px;
    pointer-events: none;
    font-weight: bold;
    display: none;
    z-index: 10;
}

#start-screen {
    position: absolute;
    top: 0; left: 0; width: 100vw; height: 100vh;
    pointer-events: none;
    display: flex;
    justify-content: center;
    z-index: 100;
}

#fly-btn {
    position: absolute;
    bottom: 40px;
    padding: 12px 24px;
    font-size: 18px;
    font-weight: bold;
    color: white;
    background-color: #BC2020;
    border: 3px solid #1a1a1a;
    border-radius: 8px;
    cursor: pointer;
    text-transform: uppercase;
    box-shadow: 0 6px 12px rgba(0,0,0,0.3);
    transition: transform 0.1s, background-color 0.2s;
    pointer-events: auto;
}

#fly-btn:hover { background-color: #e02b2b; transform: scale(1.05); }
#fly-btn:active { transform: scale(0.95); }