:root {
    --font-color: #f3f6fa;
    --background-color: #181c24;
    --card-bg: rgba(30, 34, 44, 0.253);
    --box-shadow-color: rgba(0, 0, 0, 0.35);
    --input-border-color: #2d3444;
    --button-background-color: #2196f3;
    --button-hover-color: #1769aa;
    --heading-color: #90caf9;
    --detail-border-color: #263043;
    --detail-label-color: #dae6ec;
    --detail-value-color: #f0f0f0;
    --accent: #ffb300;

    --border-radius: 15px;
}

body {
    margin: 0;
    padding: 2rem;
    font-family: 'Segoe UI', 'Roboto', Arial, sans-serif;
    background: linear-gradient(-45deg, #667eea, #764ba2, #6b8dd6, #9c6dc9);
    color: var(--font-color);
    display: flex;
    justify-content: center;
    animation: gradientShift 20s ease infinite;
    background-size: 400% 400%;
}

@keyframes reverseGradientShift {
    0% { background-position: 100% 50%; }
    50% { background-position: 0% 50%; }
    100% { background-position: 100% 50%; }
}

@keyframes gradientShift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }

    100% { background-position: 0% 50%; }
}

.container {
    max-width: 800px;
    padding: 2rem;
    background: var(--card-bg);
    border-radius: var(--border-radius);
    backdrop-filter: var(--card-blur);
    box-shadow: 0 4px 30px var(--shadow-color);
}

h1, h2, h3, h4, h5, h6 {
    color: var(--heading-color);
    font-weight: 600;
}

a {
    color: var(--heading-color);
    text-decoration: none;
    transition: color 0.2s ease;
}

a:hover {
    color: var(--accent-color);
}

ul {
    padding-left: 1.5rem;
}

.index {
    background-color: var(--card-bg);
    border-radius: 15px;
    padding: 1rem;
    margin-bottom: 2rem;
    list-style-type: none;
}

.index li {
    margin: 0.5rem 0;
}

.index-link {
    display: inline-block;
    padding: 0.4rem 0.8rem;
    border-radius: 10px;
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.1);
}

strong {
    color: var(--accent-color);
}

p, li {
    line-height: 1.6;
}

.dropdown-container {
    position: fixed;
    top: 1rem;
    left: 1rem;
    z-index: 1002;
}

.menu-button {
    font-size: 1.5rem;
    padding: 0.6rem 0.9rem;
    border: none;
    border-radius: 12px;
    background-color: var(--card-background-color);
    backdrop-filter: blur(5px);
    cursor: pointer;
    box-shadow: 2px 2px 8px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
    color: var(--font-color);
}

.menu-button:hover {
    transform: translateY(-1px);
}

.dropdown-menu {
    position: absolute;
    top: 120%;
    left: 0;
    min-width: 180px;
    background: var(--card-background-color);
    backdrop-filter: blur(8px);
    border-radius: 16px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    padding: 0.5rem;
    opacity: 0;
    transform: translateY(-10px);
    pointer-events: none;
    transition: opacity 0.3s ease, transform 0.3s ease;
    z-index: 1003;
    color: var(--font-color);
}

.dropdown-menu.show {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
}

.dropdown-menu a {
    display: block;
    padding: 0.6rem 1rem;
    text-decoration: none;
    color: var(--font-color);
    transition: background 0.2s ease;
    border-radius: 12px;
}

.dropdown-menu a:hover {
    background-color: rgba(0, 0, 0, 0.05);
}