:root {
	--bg-color: #001a44;          
	--text-white: #ffffff;
	--text-muted: #5375a3;         
	--accent-cyan: #00d2ff;        
	--green-light: #00E676;  
	--yellow-light: #ff9800;  
	--error-red: #ff5252;    
	--popup-bg: rgba(0, 18, 48, 0.85); /* 稍深的毛玻璃悬浮背景 */
}

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

body {
	font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
	background-color: var(--bg-color);
	color: var(--text-white);
	height: 100vh;
	display: flex;
	flex-direction: column;
	justify-content: space-between;
	overflow: hidden; 
	padding: 60px 80px; 
	transition: padding 0.3s ease;
}

header {
	display: flex;
	justify-content: space-between;
	align-items: center;
	width: 100%;
	max-width: 1200px;
	margin: 0 auto;
}

/* 已知晓并锁定：以后都以 52px 高度为准 */
.brand-logo {
	height: 52px; 
	display: block;
	transition: height 0.3s ease;
}

.timeline-mark {
	font-family: monospace;
	font-size: 14px;
	color: var(--text-muted);
	letter-spacing: 1px;
}

main {
	flex: 1;
	display: flex;
	flex-direction: column;
	justify-content: center;
	align-items: flex-start;
	width: 100%;
	max-width: 1200px;
	margin: 0 auto;
	padding-left: 10%; 
}

/* 核心修改：将原本的 h1 转换为自适应大图标题样式 */
.brand-logo-big {
	height: 52px; /* 保持与原 72px 字号等高的高级感视觉比例 */
	width: auto;
	display: block;
	margin-bottom: 20px;
	transition: height 0.3s ease;
}
h1 {
	font-size: 70px;
	font-weight: 500;
	letter-spacing: -2px;
	margin-bottom: 10px;
	line-height: 0.9;
	color: var(--text-white);
}

.subtitle-container {
	margin-bottom: 48px;
	max-width: 680px; 
}

.subtitle-main {
	font-size: 30px;
	color: var(--text-muted);
	line-height: 1.7;
	margin-bottom: 12px;
	font-weight: 400;
}

.subtitle-matrix {
	font-size: 14px;
	color: #324c70; 
	letter-spacing: 0.5px;
	line-height: 1.6;
	font-weight: 400;
}

.download-wrapper {
	position: relative;
	display: inline-block;
}

.btn-action {
	display: inline-flex;
	align-items: center;
	color: var(--text-white);
	text-decoration: none;
	font-size: 15px;
	font-weight: 600;
	border-bottom: 2px solid var(--text-muted);
	padding-bottom: 6px;
	transition: all 0.2s ease;
	cursor: pointer;
}

.download-wrapper:hover .btn-action,
.download-wrapper.active .btn-action {
	color: var(--accent-cyan);
	border-bottom-color: var(--accent-cyan);
}

.download-popup {
	position: absolute;
	bottom: calc(100% + 15px); /* 悬浮在按钮上方，留出15px安全间距 */
	left: 0;
	width: 320px;
	background: var(--popup-bg);
	backdrop-filter: blur(12px);
	-webkit-backdrop-filter: blur(12px);
	border: 1px solid rgba(255, 255, 255, 0.06);
	border-radius: 8px;
	padding: 12px 6px;
	box-shadow: 0 15px 35px rgba(0, 0, 0, 0.4);
	opacity: 0;
	visibility: hidden;
	transform: translateY(10px);
	transition: opacity 0.25s ease, transform 0.25s ease, visibility 0.25s;
	z-index: 100;
	max-height: 280px;
	overflow-y: auto;
}

.download-wrapper:hover .download-popup,
.download-wrapper.active .download-popup {
	opacity: 1;
	visibility: visible;
	transform: translateY(0);
}

.download-item {
	display: flex;
	justify-content: space-between;
	align-items: center;
	padding: 10px 16px;
	color: var(--text-white);
	text-decoration: none;
	font-size: 14px;
	border-radius: 50px;
	margin-bottom: 4px;
	transition: background 0.2s ease, color 0.2s ease;
}

.download-item:last-child { margin-bottom: 0; }

.download-item:hover {
	background: rgba(255, 255, 255, 0.05);
	color: var(--accent-cyan);
}

.download-item span.version {
	font-size: 12px;
	font-family: monospace;
	color: var(--text-muted);
}

.download-popup::-webkit-scrollbar {
	width: 4px; 
}

.download-popup::-webkit-scrollbar-track {
	background: transparent;
}

.download-popup::-webkit-scrollbar-thumb {
	background: rgba(83, 117, 163, 0.3); 
	border-radius: 10px;
}

.download-popup::-webkit-scrollbar-thumb:hover {
	background: var(--text-muted);
}

footer {
	display: flex;
	justify-content: space-between; /* 核心：让两端分列左右对齐 */
	align-items: center;
	width: 100%;
	max-width: 1200px;
	margin: 0 auto;
	padding: 0 10%; /* 完美对齐 main 区域的 10% 缩进线 */
	font-size: 13px;
	font-family: monospace;
	letter-spacing: 0.5px;
	color: var(--text-muted);
}

.footer-left {
	display: flex;
	gap: 30px; /* 保持原有的间距规格 */
}

.footer-right {
	font-weight: 600;
	color: #324c70; /* 高级暗灰蓝，克制不夺主 */
	letter-spacing: 1px;
	transition: color 0.2s ease;
}

.meta-item { display: flex; align-items: center; gap: 8px; }

.meta-item .green {
	color: var(--green-light);
}

.meta-item .yellow {
	color: var(--yellow-light);
}

@media (max-width: 768px) {
	body { padding: 40px 30px; }
	.brand-logo { height: 32px; } /* 手机端顶部Logo等比缩小 */
	.timeline-mark { font-size: 12px; }
	main { padding-left: 0; }
	.brand-logo-big { height: 42px; margin-bottom: 16px; } /* 手机端主体大图Logo缩小防止溢出 */
	h1 {
		font-size: 45px;
	}
	.subtitle-container { margin-bottom: 36px; }
	.subtitle-main { font-size: 25px; }
	.subtitle-matrix { font-size: 18px; }
	.download-popup { width: 280px; left: 0; bottom: calc(100% + 10px); }
	footer { 
		padding: 0; 
		flex-direction: column; 
		align-items: flex-start; /* 移动端改为左对齐 */
		gap: 16px; 
	}
	.footer-left { 
		flex-direction: column; 
		gap: 12px; 
	}
	.footer-right {
		margin-top: 4px;
		padding-top: 12px;
		border-top: 1px solid rgba(83, 117, 163, 0.15); /* 手机端增加一条极其微弱的分隔线 */
		width: 100%;
		text-align: center;
	}
}