/* General Styles & Variables */
:root {
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --background-color-light: #f4f4f9;
    --text-color-light: #333;
    --header-bg-light: #fff;
    --card-bg-light: #fff;
    --border-color-light: #ddd;
    --link-color-light: #007bff;
    --button-bg-light: #007bff;
    --button-text-light: #fff;
    --footer-bg-light: #333;
    --footer-text-light: #fff;

    --background-color-dark: #121212;
    --text-color-dark: #e0e0e0;
    --header-bg-dark: #1f1f1f;
    --card-bg-dark: #1e1e1e;
    --border-color-dark: #444;
    --link-color-dark: #6ab0f3;
    --button-bg-dark: #6ab0f3;
    --button-text-dark: #121212;
    --footer-bg-dark: #1f1f1f;
    --footer-text-dark: #e0e0e0;
}

[data-theme='light'] {
    --background-color: var(--background-color-light);
    --text-color: var(--text-color-light);
    --header-bg: var(--header-bg-light);
    --card-bg: var(--card-bg-light);
    --border-color: var(--border-color-light);
    --link-color: var(--link-color-light);
    --button-bg: var(--button-bg-light);
    --button-text: var(--button-text-light);
    --footer-bg: var(--footer-bg-light);
    --footer-text: var(--footer-text-light);
}

[data-theme='dark'] {
    --background-color: var(--background-color-dark);
    --text-color: var(--text-color-dark);
    --header-bg: var(--header-bg-dark);
    --card-bg: var(--card-bg-dark);
    --border-color: var(--border-color-dark);
    --link-color: var(--link-color-dark);
    --button-bg: var(--button-bg-dark);
    --button-text: var(--button-text-dark);
    --footer-bg: var(--footer-bg-dark);
    --footer-text: var(--footer-text-dark);
}

body {
    font-family: var(--font-family);
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.6;
    margin: 0;
    transition: background-color 0.3s, color 0.3s;
}

#container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

a {
    color: var(--link-color);
    text-decoration: none;
}
a:hover {
    text-decoration: underline;
}

/* Header */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
    background-color: var(--header-bg);
    border-bottom: 1px solid var(--border-color);
}

header h1 {
    margin: 0;
    font-size: 2.5em;
}

/* Theme Switch */
.theme-switch-wrapper {
    display: flex;
    align-items: center;
}
.theme-switch {
    position: relative;
    display: inline-block;
    width: 60px;
    height: 34px;
}
.theme-switch input { 
    opacity: 0;
    width: 0;
    height: 0;
}
.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #ccc;
    transition: .4s;
}
.slider:before {
    position: absolute;
    content: "";
    height: 26px;
    width: 26px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    transition: .4s;
}
input:checked + .slider {
    background-color: #2196F3;
}
input:checked + .slider:before {
    transform: translateX(26px);
}
.slider.round {
    border-radius: 34px;
}
.slider.round:before {
    border-radius: 50%;
}


/* Navigation */
nav {
    background-color: var(--header-bg);
    padding: 15px 20px;
    border-bottom: 1px solid var(--border-color);
}

nav a {
    margin-right: 20px;
    font-size: 1.1em;
}

/* Main Content */
main {
    padding: 20px 0;
}

main h2 {
    font-size: 2em;
    border-bottom: 2px solid var(--link-color);
    padding-bottom: 10px;
    margin-bottom: 20px;
}

/* Article List (Homepage) */
.article-list article {
    background-color: var(--card-bg);
    padding: 20px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 20px;
}

.article-list h3 {
    margin-top: 0;
}

.read-more {
    display: inline-block;
    margin-top: 10px;
    font-weight: bold;
}

/* Full Article Page */
.full-article h2 {
    border-bottom: none;
}
.full-article .meta {
    color: #888;
    font-size: 0.9em;
    margin-bottom: 20px;
}

/* Contact Form */
.contact-form .form-group {
    margin-bottom: 15px;
}
.contact-form label {
    display: block;
    margin-bottom: 5px;
}
.contact-form input, .contact-form textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    background-color: var(--background-color);
    color: var(--text-color);
    box-sizing: border-box;
}
.contact-form button {
    background-color: var(--button-bg);
    color: var(--button-text);
    border: none;
    padding: 12px 20px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1em;
}

/* Footer */
footer {
    text-align: center;
    padding: 20px;
    margin-top: 40px;
    background-color: var(--footer-bg);
    color: var(--footer-text);
}

/* Responsive Design */
@media (max-width: 600px) {
    header {
        flex-direction: column;
    }
    header h1 {
        margin-bottom: 10px;
    }
    nav a {
        display: block;
        margin-bottom: 10px;
    }
}