:root {
    --bg-color: #f4f7fc;
    --card-bg: #ffffff;
    --text-main: #4a5b6e;
    --text-title: #1e2a3e;
    --accent-main: #3b6cb0;
    --border-color: #e0e6ed;
    --card-hover-shadow: rgba(0, 0, 0, 0.06);
    --icon-color: #5c6f87;
    --hover-bg: #f8fafc;
}

[data-theme="dark"] {
    --bg-color: #0f1419;
    --card-bg: #14191f;
    --text-main: #bfbdb6;
    --text-title: #e6e1cf;
    --accent-main: #ff8f40;
    --border-color: #1f242b;
    --card-hover-shadow: rgba(0, 0, 0, 0.4);
    --icon-color: #bfbdb6;
    --hover-bg: #1a2129;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    transition: background-color 0.3s ease, color 0.3s ease;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: inherit;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 30px 0;
    border-bottom: 1px solid var(--border-color);
    transition: border-color 0.3s ease;
}

.logo {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-title);
    letter-spacing: -0.5px;
    display: flex;
    gap: 6px;
    transition: color 0.3s;
}

/* Standard logo for inner pages */
header a.logo {
    font-size: 1.4rem;
}

.logo:hover {
    color: var(--accent-main);
}

.logo span {
    color: var(--accent-main);
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 20px;
}

.social-link {
    font-weight: 500;
    font-size: 0.95rem;
    transition: color 0.2s;
}

.social-link:hover {
    color: var(--accent-main);
}

.theme-toggle {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--icon-color);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 8px;
    border-radius: 8px;
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    transition: all 0.2s;
}

.theme-toggle:hover {
    border-color: var(--accent-main);
    color: var(--accent-main);
}

svg {
    fill: currentColor;
    transition: fill 0.3s ease;
}

[data-theme="dark"] .icon-moon { display: none; }
[data-theme="light"] .icon-sun { display: none; }

footer {
    border-top: 1px solid var(--border-color);
    padding: 40px 0;
    text-align: center;
    font-size: 0.85rem;
}

footer a {
    color: var(--accent-main);
    font-weight: 500;
}

@media (max-width: 600px) {
    .header-actions { gap: 15px; }
    .social-link span { display: none; }
    .social-link::after { content: 'TG'; }
    .social-link.tw::after { content: 'TW'; }
    .social-link.yt::after { content: 'YT'; }
}