@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@400;700;900&display=swap');

body {
    margin: 0;
    overflow: hidden;
    background-color: #050510;
    font-family: 'Orbitron', "Microsoft YaHei", sans-serif;
    user-select: none;
    -webkit-user-select: none;
}

#game-container {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    z-index: 1;
}

/* UI 层 - 赛博朋克风格 */
#ui-layer {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    z-index: 2;
    pointer-events: none;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

/* 顶部 HUD */
.hud-top {
    display: flex;
    justify-content: space-between;
    padding: 30px;
    text-shadow: 0 0 10px #0ff, 0 0 20px #00f;
    z-index: 5;
}

.hud-box {
    background: rgba(0, 0, 0, 0.6);
    border: 2px solid #0ff;
    padding: 10px 20px;
    border-radius: 5px;
    transform: skewX(-15deg);
    box-shadow: 0 0 15px rgba(0, 255, 255, 0.3);
}

.hud-value {
    font-size: 32px;
    color: #fff;
    font-weight: 900;
    display: block;
    transform: skewX(15deg);
    /* 反向倾斜文字 */
}

.hud-label {
    font-size: 12px;
    color: #0ff;
    text-transform: uppercase;
    letter-spacing: 2px;
    transform: skewX(15deg);
}

/* 速度条 */
.speed-bar-container {
    width: 200px;
    height: 10px;
    background: #333;
    margin-top: 5px;
    transform: skewX(15deg);
    overflow: hidden;
}

#speed-bar-fill {
    width: 0%;
    height: 100%;
    background: linear-gradient(90deg, #0ff, #f0f);
    transition: width 0.1s;
}

/* 开始/结束屏幕 */
#start-screen,
#game-over-screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(5, 5, 16, 0.9);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 10;
    pointer-events: auto;
    backdrop-filter: blur(8px);
    transition: opacity 0.5s;
}

h1 {
    font-family: 'Orbitron', sans-serif;
    color: transparent;
    background: linear-gradient(180deg, #fff, #0ff);
    -webkit-background-clip: text;
    background-clip: text;
    font-size: 60px;
    margin-bottom: 0;
    text-transform: uppercase;
    filter: drop-shadow(0 0 20px #0ff);
    font-style: italic;
}

h2 {
    color: #f0f;
    font-size: 24px;
    text-transform: uppercase;
    letter-spacing: 5px;
    margin-top: 0;
    text-shadow: 0 0 10px #f0f;
}

p {
    color: #ccc;
    font-size: 16px;
    margin-bottom: 40px;
    text-align: center;
    line-height: 1.8;
    font-family: "Microsoft YaHei", sans-serif;
}

.btn {
    background: transparent;
    border: 2px solid #f0f;
    padding: 15px 60px;
    color: #fff;
    font-size: 24px;
    font-family: 'Orbitron', sans-serif;
    font-weight: bold;
    text-transform: uppercase;
    cursor: pointer;
    position: relative;
    overflow: hidden;
    transition: 0.3s;
    box-shadow: 0 0 20px rgba(255, 0, 255, 0.4);
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 0, 255, 0.5), transparent);
    transition: 0.5s;
}

.btn:hover {
    background: #f0f;
    color: #000;
    box-shadow: 0 0 40px #f0f;
}

.btn:hover::before {
    left: 100%;
}

/* 移动端控制 */
#mobile-controls {
    display: none;
    width: 100%;
    height: 150px;
    padding-bottom: 30px;
    pointer-events: auto;
    justify-content: space-between;
    padding: 0 40px;
    box-sizing: border-box;
}

.control-btn {
    width: 90px;
    height: 90px;
    background: rgba(0, 255, 255, 0.1);
    border: 2px solid rgba(0, 255, 255, 0.5);
    border-radius: 50%;
    transform: rotate(45deg);
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(4px);
    transition: 0.1s;
}

.control-btn span {
    transform: rotate(-45deg);
    font-size: 40px;
    color: #0ff;
    pointer-events: none;
}

.control-btn:active {
    background: rgba(0, 255, 255, 0.6);
    border-color: #fff;
    box-shadow: 0 0 30px #0ff;
}

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

#sun-background {
    position: absolute;
    width: 100%;
    height: 60%;
    bottom: 0;
    background: linear-gradient(to top, rgba(255, 0, 255, 0.2), transparent);
    z-index: 0;
    pointer-events: none;
}