:root {
    --glass-bg: rgba(255, 255, 255, 0.15);
    --glass-border: rgba(255, 255, 255, 0.2);
    --text-color: #000000;
    --shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    min-height: 100vh;
    color: var(--text-color);
    background-color: #f0f0f0;
    background-image: url('asset/htmlserver.png'), linear-gradient(120deg, #fdfbfb 0%, #ebedee 100%);
    background-size: cover;
    background-repeat: no-repeat;
    background-position: center;
}

.glass-container {
    width: 100%;
    min-height: 100vh;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    gap: 2rem;
    opacity: 0;
    animation: fadeIn 1.2s ease-in-out forwards;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.glass-header, .glass-main, .glass-footer, .glass-card, .glass-button {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 1rem;
    padding: 1.5rem;
    box-shadow: var(--shadow);
}

.glass-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.glass-main {
    flex: 1;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.glass-card {
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.glass-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.15);
}

.glass-button {
    padding: 0.8rem 1.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
    background: rgba(255, 255, 255, 0.25);
}

.glass-button:hover {
    background: rgba(255, 255, 255, 0.25);
}

#background-upload {
    display: none;
}

footer {
    text-align: center;
    margin-top: auto;
}

@media (max-width: 768px) {
    .glass-container {
        padding: 1rem;
    }
    .glass-header {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
}