:root {
    --primary-blue: #0058D3;
    --primary-red: #FD0000;
    --text-color: #333333;
    --bg-color: #f4f7f6;
    --white: #ffffff;
    --gray-light: #e0e0e0;
    --gray-dark: #555555;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    --border-radius: 8px;
}

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

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

a {
    text-decoration: none;
    color: var(--primary-blue);
    transition: color 0.2s ease-in-out;
}

a:hover {
    color: var(--primary-red);
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 15px;
}

/* Header */
.top-stripe {
    background-color: var(--primary-blue);
    height: 6px;
    width: 100%;
}
.main-header {
    background-color: var(--white);
    padding: 15px 0;
    box-shadow: var(--shadow);
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 15px;
}

.logo {
    display: flex;
    flex-direction: column;
}

.logo-top {
    display: flex;
    flex-direction: row;
    align-items: baseline;
}

.logo-inz {
    color: var(--primary-blue);
    font-size: 32px;
    font-weight: 700;
    font-style: italic;
    line-height: 1;
}

.logo-tri {
    color: var(--primary-red);
    font-size: 32px;
    font-weight: 700;
    font-style: italic;
    line-height: 1;
}

.logo-sub {
    font-size: 12px;
    color: var(--gray-dark);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-top: 5px;
}

.header-links {
    display: flex;
    flex-direction: column;
    gap: 5px;
    font-size: 13px;
    color: var(--gray-dark);
}

.header-links a {
    color: var(--gray-dark);
}
.header-links a:hover {
    color: var(--primary-blue);
}

/* Main Layout */
.main-content {
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: 30px;
    margin-top: 30px;
    margin-bottom: 50px;
}

@media (max-width: 768px) {
    .main-content {
        grid-template-columns: 1fr;
    }
}

/* Sidebar */
.sidebar {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.btn-add-ad {
    display: block;
    background-color: var(--primary-red);
    color: var(--white);
    text-align: center;
    padding: 12px;
    border-radius: var(--border-radius);
    font-weight: 600;
    font-size: 16px;
    box-shadow: var(--shadow);
    transition: transform 0.2s, background-color 0.2s;
}

.btn-add-ad:hover {
    background-color: #d10000;
    color: var(--white);
    transform: translateY(-2px);
}

.categories-nav {
    display: flex;
    flex-direction: column;
    background: var(--white);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
}

.categories-nav a {
    padding: 12px 15px;
    border-bottom: 1px solid var(--gray-light);
    color: #444;
    font-weight: 500;
    transition: background 0.2s, color 0.2s;
}

.categories-nav a:last-child {
    border-bottom: none;
}

.categories-nav a:hover, .categories-nav a.active {
    background-color: var(--primary-blue);
    color: var(--white);
    padding-left: 20px; /* hover effect */
}

.search-box, .user-box {
    background: var(--white);
    padding: 15px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}

.search-box h3, .user-box h3 {
    font-size: 14px;
    background-color: #333;
    color: #fff;
    padding: 8px;
    margin: -15px -15px 15px -15px;
    border-radius: var(--border-radius) var(--border-radius) 0 0;
}

.search-box form {
    display: flex;
}

.search-box input[type="text"] {
    flex: 1;
    padding: 8px;
    border: 1px solid var(--gray-light);
    border-radius: 4px 0 0 4px;
    outline: none;
}

.search-box button {
    padding: 8px 12px;
    background-color: #666;
    color: white;
    border: none;
    border-radius: 0 4px 4px 0;
    cursor: pointer;
}

.footer-nav {
    display: flex;
    flex-direction: column;
    gap: 5px;
    font-size: 13px;
    margin-top: 10px;
}

/* Content Area */
.content-area {
    background: var(--white);
    padding: 25px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
}

.page-title {
    color: var(--primary-blue);
    border-bottom: 2px solid var(--gray-light);
    padding-bottom: 10px;
    margin-bottom: 20px;
}

/* Posts List */
.post-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.post-item {
    background: var(--white);
    padding: 15px;
    border-radius: var(--border-radius);
    display: flex;
    gap: 15px;
    box-shadow: var(--shadow);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.post-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1);
}

.post-image {
    width: 150px;
    height: 110px;
    object-fit: cover;
    border-radius: 4px;
    flex-shrink: 0;
}

.post-content {
    flex-grow: 1;
}

.post-header {
    font-size: 12px;
    color: var(--gray-dark);
    margin-bottom: 5px;
    display: flex;
    justify-content: space-between;
}

.post-title {
    font-size: 18px;
    margin-bottom: 5px;
}

.post-title a {
    color: var(--primary-blue);
    text-decoration: none;
}

.post-title a:hover {
    text-decoration: underline;
}

.post-price {
    font-weight: 700;
    color: var(--primary-red);
    font-size: 18px;
    margin-bottom: 5px;
}

.post-contact {
    font-size: 14px;
    color: var(--gray-dark);
    margin-top: 10px;
}

/* Detail page */
.detail-title {
    font-size: 24px;
    color: var(--primary-blue);
    margin-bottom: 15px;
}

.detail-meta {
    font-size: 14px;
    color: var(--gray-dark);
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--gray-light);
}

.detail-image {
    max-width: 100%;
    border-radius: var(--border-radius);
    margin-bottom: 20px;
}

.detail-desc {
    font-size: 16px;
    line-height: 1.7;
    margin-bottom: 30px;
    white-space: pre-line;
}

.detail-price {
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-red);
    margin-bottom: 20px;
}

.detail-contact-box {
    background: var(--bg-color);
    padding: 20px;
    border-radius: var(--border-radius);
    border: 1px solid var(--gray-light);
}

/* Forms */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 4px;
    font-family: 'Inter', sans-serif;
}

textarea.form-control {
    min-height: 150px;
    resize: vertical;
}

.btn-submit {
    background-color: var(--primary-red);
    color: var(--white);
    border: none;
    padding: 12px 25px;
    border-radius: var(--border-radius);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s;
}

.btn-submit:hover {
    background-color: #d10000;
}

.main-footer {
    text-align: center;
    padding: 20px 0;
    color: var(--gray-dark);
    font-size: 14px;
}