:root {
    --primary: #0f766e;
    --primary-dark: #115e59;
    --accent: #f59e0b;
    --bg: #f3f4f6;
    --card: #ffffff;
    --text: #111827;
    --muted: #6b7280;
    --danger: #b91c1c;
    --border: #e5e7eb;
    --radius: 10px;
    --shadow: 0 8px 24px rgba(15, 23, 42, 0.08);
}

* {
    box-sizing: border-box;
}

html, body {
    margin: 0;
    padding: 0;
    font-family: Arial, Helvetica, sans-serif;
    background: var(--bg);
    color: var(--text);
}

a {
    color: var(--primary-dark);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

.topbar {
    background: var(--primary);
    color: #fff;
    padding: 10px 16px;
    box-shadow: var(--shadow);
}

.brand a {
    color: #fff;
    font-size: 18px;
}

.main-nav ul {
    list-style: none;
    margin: 10px 0 0;
    padding: 0;
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
}

.main-nav li {
    position: relative;
}

.main-nav a,
.main-nav summary {
    display: inline-block;
    padding: 8px 12px;
    color: #fff;
    border-radius: 6px;
    cursor: pointer;
    white-space: nowrap;
}

.main-nav a:hover,
.main-nav summary:hover,
.main-nav a.active {
    background: rgba(255, 255, 255, 0.15);
    text-decoration: none;
}

.main-nav details ul {
    display: block;
    position: static;
    background: transparent;
    box-shadow: none;
    margin-left: 12px;
}

@media (min-width: 900px) {
    .main-nav details {
        position: relative;
    }

    .main-nav details ul {
        position: absolute;
        top: 100%;
        left: 0;
        min-width: 280px;
        background: #fff;
        box-shadow: var(--shadow);
        border-radius: 8px;
        padding: 6px;
        z-index: 999;
    }

    .main-nav details ul a {
        color: var(--text);
        display: block;
    }

    .main-nav details ul a:hover {
        background: #f9fafb;
    }
}

main {
    max-width: 1280px;
    margin: 20px auto;
    padding: 0 16px;
}

.card {
    background: var(--card);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 18px;
    margin-bottom: 18px;
}

.hero {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #fff;
}

.hero h1 {
    margin-top: 0;
}

.hero a.btn-outline {
    color: #fff;
    border-color: #fff;
}

.hero-actions {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-top: 14px;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 14px;
}

.stats-grid {
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
}

.stat-box {
    background: #f8fafc;
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 14px;
    text-align: center;
}

.stat-box span {
    display: block;
    color: var(--muted);
    margin-bottom: 6px;
}

.stat-box strong {
    font-size: 24px;
}

.item-card {
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 14px;
    background: #fff;
}

.item-card h3 {
    margin: 0 0 8px;
    font-size: 16px;
}

.toolbar {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    flex-wrap: wrap;
    margin-bottom: 14px;
}

.search-form {
    display: flex;
    gap: 8px;
    flex: 1;
    min-width: 260px;
}

.toolbar-actions {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

table {
    width: 100%;
    border-collapse: collapse;
    background: #fff;
}

th, td {
    padding: 10px;
    border-bottom: 1px solid var(--border);
    vertical-align: top;
}

th {
    background: #f9fafb;
    text-align: left;
}

.btn {
    display: inline-block;
    padding: 9px 14px;
    border-radius: 6px;
    background: var(--primary);
    color: #fff;
    border: 1px solid var(--primary);
    cursor: pointer;
    font-size: 14px;
}

.btn:hover {
    background: var(--primary-dark);
    text-decoration: none;
}

.btn-outline {
    background: transparent;
    color: var(--primary-dark);
    border-color: var(--primary);
}

.btn-danger {
    background: var(--danger);
    border-color: var(--danger);
}

.btn-small {
    padding: 6px 10px;
    font-size: 13px;
}

.inline {
    display: inline-block;
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 14px;
}

.form-field.full {
    grid-column: 1 / -1;
}

label {
    display: block;
    margin-bottom: 6px;
    font-weight: 600;
}

.form-control {
    width: 100%;
    padding: 10px;
    border: 1px solid #cbd5e1;
    border-radius: 6px;
    font-size: 14px;
    background: #fff;
}

textarea.form-control {
    min-height: 120px;
}

.alert {
    padding: 12px 14px;
    border-radius: 8px;
    margin-bottom: 14px;
}

.alert-success {
    background: #dcfce7;
    color: #166534;
    border: 1px solid #86efac;
}

.alert-error {
    background: #fee2e2;
    color: #991b1b;
    border: 1px solid #fca5a5;
}

.attachments {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 12px;
    margin: 12px 0;
}

.attachment-item {
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 8px;
    background: #fff;
}

.attachment-item img,
.attachment-item video {
    width: 100%;
    border-radius: 6px;
    display: block;
    margin-bottom: 8px;
}

.attach-delete {
    font-weight: normal;
    font-size: 13px;
}

.comment {
    border-left: 4px solid var(--primary);
    background: #f8fafc;
    padding: 10px 12px;
    margin: 10px 0;
    border-radius: 0 8px 8px 0;
}

.pagination {
    margin-top: 14px;
    display: flex;
    gap: 6px;
    flex-wrap: wrap;
}

.pagination .active {
    background: var(--primary-dark);
}

.detail-table th {
    width: 240px;
}

.auth-card {
    max-width: 520px;
    margin: 30px auto;
}

.quick-links {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

footer {
    text-align: center;
    padding: 20px;
    color: var(--muted);
    font-size: 13px;
}

@media print {
    .topbar, footer, .toolbar, .btn, form, .pagination {
        display: none !important;
    }

    body {
        background: #fff;
    }

    .card {
        box-shadow: none;
        border: 1px solid #ddd;
    }
}

.chat-layout {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 16px;
}

.chat-sidebar,
.chat-main {
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 14px;
    background: #fff;
}

.chat-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin: 12px 0;
}

.chat-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px;
    border: 1px solid var(--border);
    border-radius: 10px;
    text-decoration: none;
    color: inherit;
}

.chat-item:hover {
    background: #f8fafc;
    text-decoration: none;
}

.chat-item-body {
    flex: 1;
    min-width: 0;
}

.chat-item-body strong {
    display: block;
}

.chat-item-body small {
    display: block;
    color: var(--muted);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.chat-badge {
    background: var(--danger);
    color: #fff;
    border-radius: 999px;
    padding: 2px 8px;
    font-size: 12px;
}

.chat-avatar,
.chat-avatar-small,
.chat-avatar-large {
    display: inline-grid;
    place-items: center;
    border-radius: 999px;
    object-fit: cover;
    background: var(--primary);
    color: #fff;
    font-weight: 700;
}

.chat-avatar {
    width: 48px;
    height: 48px;
}

.chat-avatar-small {
    width: 36px;
    height: 36px;
    font-size: 14px;
}

.chat-avatar-large {
    width: 92px;
    height: 92px;
    font-size: 32px;
    margin-bottom: 12px;
}

.chat-avatar-initial {
    background: linear-gradient(135deg, var(--primary), var(--accent));
}

.chat-peer {
    text-align: center;
}

.chat-peer .btn {
    margin-top: 10px;
}

.chat-messages {
    min-height: 320px;
    max-height: 520px;
    overflow: auto;
    padding: 10px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: #f8fafc;
    margin-bottom: 14px;
}

.chat-bubble {
    max-width: 75%;
    margin: 10px 0;
    padding: 10px 12px;
    border-radius: 12px;
    background: #fff;
    border: 1px solid var(--border);
}

.chat-bubble.mine {
    margin-left: auto;
    background: #dcfce7;
    border-color: #86efac;
}

.chat-bubble.theirs {
    margin-right: auto;
}

.chat-bubble-meta {
    font-size: 11px;
    color: var(--muted);
    margin-bottom: 6px;
}

.chat-bubble-body {
    white-space: normal;
}

.chat-form .form-control {
    margin-bottom: 10px;
}

.chat-placeholder {
    display: grid;
    place-items: center;
    min-height: 320px;
    text-align: center;
    color: var(--muted);
}

@media (max-width: 900px) {
    .chat-layout {
        grid-template-columns: 1fr;
    }
}