:root {
    --bg-color: #f8fafc;    
    --card-bg: #ffffff;    
    --text-main: #0f172a;  
    --text-body: #475569;  
    --accent: #2563eb;     
    --border: rgba(0, 0, 0, 0.06);
    --nav-height: 70px;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', -apple-system, sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-body);
    line-height: 1.7;
}

nav {
    position: fixed;
    top: 0;
    width: 100%;
    height: var(--nav-height);
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 5%;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    z-index: 1000;
}

.logo {
    font-size: 1.25rem;
    font-weight: 800;
    color: var(--text-main);
    text-decoration: none;
    letter-spacing: -0.5px;
}

.nav-links a {
    color: var(--text-body);
    text-decoration: none;
    margin-left: 2rem;
    font-size: 0.95rem;
    font-weight: 500;
    transition: 0.2s;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--accent);
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 140px 24px 80px;
}

h1 {
    font-size: 3.5rem;
    font-weight: 800;
    color: var(--text-main);
    line-height: 1.2;
    margin-bottom: 1.5rem;
    letter-spacing: -1px;
}

h2 {
    font-size: 2rem;
    color: var(--text-main);
    margin-bottom: 1.5rem;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
}

.card {
    background: var(--card-bg);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 32px;
    box-shadow: var(--shadow);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

.card h3 {
    color: var(--text-main);
    margin-bottom: 12px;
}

.btn {
    display: inline-block;
    padding: 14px 28px;
    background: var(--accent);
    color: #ffffff;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    box-shadow: 0 4px 14px 0 rgba(37, 99, 235, 0.39);
    transition: 0.3s;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(37, 99, 235, 0.23);
}

.fade-up {
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.6s ease-out;
}

.fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

img {
    max-width: 100%;
    height: auto;
    border-radius: 12px;
    background-color: #e2e8f0;
}

nav {
    position: fixed;
    top: 0;
    width: 100%;
    height: 70px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 5%;
    background: #ffffff; /* 不支援特效時，直接顯示純白 */
    border-bottom: 1px solid rgba(0,0,0,0.1);
    z-index: 1000;
}

@supports ((-webkit-backdrop-filter: blur(12px)) or (backdrop-filter: blur(12px))) {
    nav {
        background: rgba(255, 255, 255, 0.7);
        -webkit-backdrop-filter: blur(12px);
        backdrop-filter: blur(12px);
    }
}

footer {
    width: 100%;
    padding: 40px 0;
    margin-top: 60px;
    border-top: 1px solid var(--border);

    display: flex;
    justify-content: center;
    align-items: center;    
    
    color: var(--text-body);
    font-size: 0.85rem;
    background-color: var(--bg-color);
}

footer p {
    margin: 0; 
    text-align: center;
}