:root {
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --up-color: #ef4444;
    --down-color: #3b82f6;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --border-radius: 12px;
}

body.light-mode {
    --bg: #f8fafc;
    --card-bg: #ffffff;
    --text-main: #1e293b;
    --text-muted: #64748b;
    --border: #e2e8f0;
    --header-bg: rgba(255, 255, 255, 0.85);
    --ticker-bg: #0f172a;
    --ticker-text: #f8fafc;
    --info-bar-bg: #1e293b;
}

body.dark-mode {
    --bg: #0f172a;
    --card-bg: #1e293b;
    --text-main: #f1f5f9;
    --text-muted: #94a3b8;
    --border: #334155;
    --header-bg: rgba(15, 23, 42, 0.85);
    --ticker-bg: #000000;
    --ticker-text: #f1f5f9;
    --info-bar-bg: #000000;
}

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

body {
    font-family: 'Pretendard', sans-serif;
    background-color: var(--bg);
    color: var(--text-main);
    line-height: 1.6;
    transition: background-color var(--transition), color var(--transition);
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 1.5rem; }

/* User Info Bar */
.user-info-bar {
    background-color: var(--info-bar-bg);
    color: white;
    text-align: center;
    padding: 6px 0;
    font-size: 0.8rem;
    font-weight: 600;
}

/* Header */
.main-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background-color: var(--header-bg);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    height: 70px;
}

.header-content { display: flex; justify-content: space-between; align-items: center; height: 100%; }
.logo { font-size: 1.5rem; font-weight: 800; text-decoration: none; color: inherit; }
.logo span { color: var(--primary); }

.main-nav ul { display: flex; gap: 2rem; list-style: none; }
.main-nav a { text-decoration: none; color: inherit; font-weight: 600; }
.main-nav a:hover { color: var(--primary); }

/* Hero Section (Centered) */
.general-hero { padding: 100px 0; text-align: center; background: radial-gradient(circle at center, rgba(37, 99, 235, 0.08), transparent); }
.hero-content-centered { max-width: 800px; margin: 0 auto; }
.hero-content-centered h2 { font-size: 3.5rem; margin-bottom: 1.5rem; line-height: 1.2; }
.hero-content-centered h2 span { color: var(--primary); }
.hero-content-centered p { font-size: 1.25rem; color: var(--text-muted); margin-bottom: 2.5rem; }
.hero-btns { display: flex; gap: 1rem; justify-content: center; }

/* Category Grid */
.category-section { padding: 60px 0; }
.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}
.cat-card {
    background-color: var(--card-bg);
    padding: 2rem 1.5rem;
    border-radius: var(--border-radius);
    border: 1px solid var(--border);
    text-align: center;
    text-decoration: none;
    color: inherit;
    transition: all 0.2s;
}
.cat-card:hover { transform: translateY(-5px); border-color: var(--primary); box-shadow: 0 10px 20px rgba(0,0,0,0.05); }
.cat-card i { display: block; font-size: 2.5rem; margin-bottom: 1rem; font-style: normal; }
.cat-card span { font-weight: 700; font-size: 1.1rem; }

/* Buttons */
.btn { padding: 0.75rem 1.5rem; border-radius: var(--border-radius); font-weight: 700; border: none; cursor: pointer; text-decoration: none; display: inline-block; transition: 0.2s; }
.btn-primary { background-color: var(--primary); color: white; }
.btn-primary:hover { background-color: var(--primary-hover); }
.btn-secondary { background-color: var(--card-bg); border: 1px solid var(--border); color: var(--text-main); }
.btn-outline { background: transparent; border: 1px solid var(--border); color: var(--text-main); }
.btn-sm { padding: 0.5rem 1rem; font-size: 0.85rem; }

/* Forms & Write Page */
.auth-container { max-width: 500px; margin: 60px auto; background-color: var(--card-bg); padding: 2.5rem; border-radius: var(--border-radius); border: 1px solid var(--border); }
.write-container { max-width: 800px; }
.form-group { margin-bottom: 1.5rem; }
.form-group label { display: block; margin-bottom: 0.5rem; font-weight: 600; }
.form-group input, .form-group textarea, .form-group select {
    width: 100%; padding: 0.85rem; border-radius: 8px; border: 1px solid var(--border); background-color: var(--bg); color: var(--text-main); outline: none; font-family: inherit;
}
.auth-btn { width: 100%; padding: 1rem; background-color: var(--primary); color: white; border: none; border-radius: 8px; font-weight: 700; cursor: pointer; }

/* Community Page */
.community-grid { display: grid; grid-template-columns: 220px 1fr 280px; gap: 2rem; margin-top: 40px; }
.sidebar-nav a { display: block; padding: 12px 16px; border-radius: 8px; text-decoration: none; color: var(--text-main); font-weight: 600; margin-bottom: 4px; }
.sidebar-nav a:hover, .sidebar-nav a.active { background-color: var(--primary); color: white; }

.discussion-item { background-color: var(--card-bg); padding: 1.25rem; border-radius: var(--border-radius); border: 1px solid var(--border); display: flex; align-items: center; gap: 1.5rem; margin-bottom: 1rem; text-decoration: none; color: inherit; transition: 0.2s; }
.discussion-item:hover { transform: translateX(8px); border-color: var(--primary); }
.vote-box { display: flex; flex-direction: column; align-items: center; min-width: 50px; padding: 8px; background-color: var(--bg); border-radius: 8px; }
.vote-box .count { font-weight: 700; }
.post-info { flex: 1; }
.tag { padding: 4px 10px; border-radius: 4px; font-size: 0.75rem; font-weight: 700; background-color: var(--bg); }

.discussion-list.full-content .discussion-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
}

.discussion-list.full-content .post-content {
    margin-top: 10px;
    font-size: 0.95rem;
    color: var(--text-main);
    white-space: pre-wrap;
}

.discussion-list.full-content .post-image {
    max-width: 100%;
    border-radius: 8px;
    margin-top: 15px;
    border: 1px solid var(--border);
}

.discussion-list.full-content .post-header {
    display: flex;
    justify-content: space-between;
    width: 100%;
    align-items: center;
}

.auth-btns { display: flex; align-items: center; gap: 10px; }
.user-name { font-weight: 600; font-size: 0.9rem; color: var(--text-main); }

/* Footer */
.main-footer { padding: 60px 0; border-top: 1px solid var(--border); text-align: center; color: var(--text-muted); }

@media (max-width: 992px) {
    .community-grid { grid-template-columns: 1fr; }
    .community-sidebar, .community-widgets { display: none; }
    .hero-content-centered h2 { font-size: 2.5rem; }
}