/* --- Cài đặt chung & Reset cơ bản --- */
:root {
    --primary-color: #007bff; /* Màu chủ đạo (ví dụ: xanh dương) */
    --secondary-color: #6c757d; /* Màu phụ (ví dụ: xám) */
    --success-color: #28a745; /* Màu thành công (ví dụ: xanh lá) */
    --danger-color: #dc3545; /* Màu nguy hiểm/lỗi (ví dụ: đỏ) */
    --warning-color: #ffc107; /* Màu cảnh báo (ví dụ: vàng) */
    --info-color: #17a2b8; /* Màu thông tin (ví dụ: xanh lơ) */
    --light-color: #f8f9fa; /* Màu sáng (nền, v.v.) */
    --dark-color: #343a40; /* Màu tối (chữ, nền header/footer) */
    --text-color: #212529; /* Màu chữ chính */
    --text-muted: #6c757d; /* Màu chữ mờ */
    --border-color: #dee2e6; /* Màu viền */
    --font-family-sans-serif: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji";
    --font-family-monospace: SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    font-family: var(--font-family-sans-serif);
    line-height: 1.6;
    -webkit-text-size-adjust: 100%;
    -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
}

body {
    margin: 0;
    font-size: 1rem;
    font-weight: 400;
    color: var(--text-color);
    background-color: #e9ecef; /* Màu nền tổng thể nhẹ nhàng hơn */
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.container {
    width: 100%;
    padding-right: 15px;
    padding-left: 15px;
    margin-right: auto;
    margin-left: auto;
}

@media (min-width: 576px) {
    .container { max-width: 540px; }
}
@media (min-width: 768px) {
    .container { max-width: 720px; }
}
@media (min-width: 992px) {
    .container { max-width: 960px; }
}
@media (min-width: 1200px) {
    .container { max-width: 1140px; }
}

a {
    color: var(--primary-color);
    text-decoration: none;
    background-color: transparent;
}
a:hover {
    color: darken(var(--primary-color), 10%);
    text-decoration: underline;
}

img {
    vertical-align: middle;
    border-style: none;
}

/* --- Header (Người dùng) --- */
.main-header {
    background-color: var(--dark-color);
    color: var(--light-color);
    padding: 1rem 0;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.main-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.main-header .site-title a {
    color: #fff;
    font-size: 1.75rem;
    font-weight: bold;
    text-decoration: none;
}

.main-nav ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    align-items: center;
}

.main-nav ul li {
    margin-left: 20px;
}

.main-nav ul li a {
    color: #bdc3c7; /* Màu chữ liên kết nhạt hơn */
    text-decoration: none;
    padding: 0.5rem 0.75rem;
    border-radius: 4px;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.main-nav ul li a:hover,
.main-nav ul li a.active {
    background-color: rgba(255, 255, 255, 0.1);
    color: #fff;
    text-decoration: none;
}

.main-nav .user-info {
    color: #ecf0f1;
    font-size: 0.9rem;
}
.main-nav .user-info a{ /* For logout link specifically if it's part of user-info */
    font-weight: bold;
    color: var(--warning-color);
}


/* --- Khu vực nội dung chính --- */
.main-content-area {
    flex: 1; /* Cho sticky footer */
    padding: 25px 15px; /* Thêm padding cho .container bên trong nó */
    background-color: #fff;
    border-radius: 0; /* Bỏ border-radius nếu .container xử lý */
    box-shadow: none; /* Bỏ box-shadow nếu .container xử lý */
    margin-top: 0; /* Gắn liền với header */
}
.main-content-area .container { /* Thêm style cho container bên trong main-content-area */
    background-color: #fff;
    padding: 20px 25px;
    border-radius: 8px;
    box-shadow: 0 0 15px rgba(0,0,0,0.07);
}


h1, h2, h3, h4, h5, h6 {
    margin-top: 0;
    margin-bottom: 0.75rem;
    font-weight: 500;
    line-height: 1.2;
    color: var(--dark-color);
}
h1 { font-size: 2.25rem; }
h2 { font-size: 1.8rem; }
h3 { font-size: 1.5rem; }

p {
    margin-top: 0;
    margin-bottom: 1rem;
}

/* --- Forms --- */
.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: inline-block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #495057;
}

.form-control {
    display: block;
    width: 100%;
    padding: 0.5rem 0.85rem;
    font-size: 1rem;
    font-weight: 400;
    line-height: 1.5;
    color: #495057;
    background-color: #fff;
    background-clip: padding-box;
    border: 1px solid var(--border-color);
    border-radius: 0.25rem;
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}
.form-control:focus {
    border-color: lighten(var(--primary-color), 25%);
    outline: 0;
    box-shadow: 0 0 0 0.2rem rgba(var(--primary-color), 0.25);
}

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

select.form-control {
    height: calc(1.5em + 1rem + 2px); /* Chỉnh chiều cao cho select */
}

.btn {
    display: inline-block;
    font-weight: 400;
    color: var(--text-color);
    text-align: center;
    vertical-align: middle;
    cursor: pointer;
    user-select: none;
    background-color: transparent;
    border: 1px solid transparent;
    padding: 0.5rem 1rem;
    font-size: 1rem;
    line-height: 1.5;
    border-radius: 0.25rem;
    transition: color 0.15s ease-in-out, background-color 0.15s ease-in-out, border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
}

.btn-primary {
    color: #fff;
    background-color: var(--primary-color);
    border-color: var(--primary-color);
}
.btn-primary:hover {
    color: #fff;
    background-color: darken(var(--primary-color), 7.5%);
    border-color: darken(var(--primary-color), 10%);
    text-decoration: none;
}

.btn-secondary {
    color: #fff;
    background-color: var(--secondary-color);
    border-color: var(--secondary-color);
}
.btn-secondary:hover {
    color: #fff;
    background-color: darken(var(--secondary-color), 7.5%);
    border-color: darken(var(--secondary-color), 10%);
    text-decoration: none;
}
.btn-success { color: #fff; background-color: var(--success-color); border-color: var(--success-color); }
.btn-success:hover { background-color: darken(var(--success-color), 7.5%); border-color: darken(var(--success-color), 10%); text-decoration: none; }
.btn-danger { color: #fff; background-color: var(--danger-color); border-color: var(--danger-color); }
.btn-danger:hover { background-color: darken(var(--danger-color), 7.5%); border-color: darken(var(--danger-color), 10%); text-decoration: none; }
.btn-warning { color: var(--text-color); background-color: var(--warning-color); border-color: var(--warning-color); }
.btn-warning:hover { background-color: darken(var(--warning-color), 7.5%); border-color: darken(var(--warning-color), 10%); text-decoration: none; }


.form-actions {
    margin-top: 1.5rem;
}

/* Thông báo lỗi/thành công */
.alert {
    position: relative;
    padding: 0.85rem 1.25rem;
    margin-bottom: 1rem;
    border: 1px solid transparent;
    border-radius: 0.25rem;
}
.alert-danger {
    color: #721c24;
    background-color: #f8d7da;
    border-color: #f5c6cb;
}
.alert-success {
    color: #155724;
    background-color: #d4edda;
    border-color: #c3e6cb;
}
.alert-info {
    color: #0c5460;
    background-color: #d1ecf1;
    border-color: #bee5eb;
}


/* --- Bảng (ví dụ: My Tickets) --- */
.tickets-table {
    width: 100%;
    margin-bottom: 1rem;
    color: var(--text-color);
    border-collapse: collapse; /* Quan trọng hơn */
}

.tickets-table th,
.tickets-table td {
    padding: 0.85rem;
    vertical-align: top;
    border-top: 1px solid var(--border-color);
}

.tickets-table thead th {
    vertical-align: bottom;
    border-bottom: 2px solid var(--border-color);
    background-color: var(--light-color);
    font-weight: 500;
    text-align: left;
}

.tickets-table tbody tr:nth-of-type(odd) {
    background-color: rgba(0,0,0,.03);
}
.tickets-table tbody tr:hover {
    background-color: rgba(0,0,0,.06);
}

.tickets-table .ticket-actions a {
    margin-right: 0.5rem;
}

/* Trạng thái và độ ưu tiên trong bảng */
.status-badge, .priority-badge {
    padding: 0.25em 0.6em;
    font-size: 0.85em;
    font-weight: 500;
    line-height: 1;
    text-align: center;
    white-space: nowrap;
    vertical-align: baseline;
    border-radius: 0.25rem;
    color: #fff;
}
.status-open { background-color: var(--warning-color); color: var(--dark-color); }
.status-pending_customer_reply { background-color: var(--info-color); }
.status-pending_agent_reply { background-color: var(--primary-color); }
.status-resolved { background-color: var(--success-color); }
.status-closed { background-color: var(--secondary-color); }

.priority-low { background-color: var(--info-color); }
.priority-medium { background-color: var(--primary-color); }
.priority-high { background-color: var(--warning-color); color: var(--dark-color); }
.priority-urgent { background-color: var(--danger-color); }


/* --- Xem Ticket Chi Tiết (View Ticket) --- */
.ticket-details-card {
    background-color: #fff;
    border: 1px solid var(--border-color);
    border-radius: 0.3rem;
    margin-bottom: 1.5rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}
.ticket-details-header {
    padding: 1rem 1.25rem;
    background-color: var(--light-color);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.ticket-details-header h2 {
    margin-bottom: 0;
    font-size: 1.5rem;
}
.ticket-details-body {
    padding: 1.25rem;
}
.ticket-info p { margin-bottom: 0.5rem; }
.ticket-info strong { margin-right: 5px; color: #555; }

.ticket-conversation {
    margin-top: 2rem;
}
.ticket-conversation h3 {
    margin-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.message-item {
    padding: 1rem;
    margin-bottom: 1rem;
    border-radius: 0.25rem;
    border: 1px solid var(--border-color);
    position: relative;
}
.message-item.user-reply { /* Tin nhắn của người dùng */
    background-color: #e9f5ff; /* Màu xanh nhạt */
    border-left: 3px solid var(--primary-color);
}
.message-item.admin-reply { /* Tin nhắn của admin */
    background-color: #f8f9fa; /* Màu xám nhạt */
    border-left: 3px solid var(--secondary-color);
}
.message-meta {
    font-size: 0.85em;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}
.message-meta strong {
    color: var(--text-color);
}
.message-content p:last-child {
    margin-bottom: 0;
}

.reply-form-container {
    margin-top: 2rem;
    padding: 1.5rem;
    background-color: var(--light-color);
    border-radius: 0.3rem;
    border: 1px solid var(--border-color);
}
.reply-form-container h3 {
    margin-bottom: 1rem;
}


/* --- Footer --- */
.main-footer {
    background-color: var(--dark-color);
    color: #bdc3c7;
    text-align: center;
    padding: 1.5rem 0;
    margin-top: auto; /* Đẩy footer xuống cuối nếu nội dung không đủ dài */
    font-size: 0.9em;
}
.main-footer .container {
    /* Container của footer đã được style ở trên */
}
.main-footer p {
    margin: 0;
}

/* --- Tiện ích --- */
.text-center { text-align: center !important; }
.mt-1 { margin-top: 0.25rem !important; }
.mt-2 { margin-top: 0.5rem !important; }
.mt-3 { margin-top: 1rem !important; }
.mt-4 { margin-top: 1.5rem !important; }
.mt-5 { margin-top: 3rem !important; }
.mb-1 { margin-bottom: 0.25rem !important; }
.mb-2 { margin-bottom: 0.5rem !important; }
.mb-3 { margin-bottom: 1rem !important; }
.mb-4 { margin-bottom: 1.5rem !important; }
.mb-5 { margin-bottom: 3rem !important; }

/* --- Responsive cơ bản --- */
@media (max-width: 768px) {
    .main-header .container {
        flex-direction: column;
        align-items: flex-start;
    }
    .main-nav ul {
        flex-direction: column;
        width: 100%;
        margin-top: 1rem;
    }
    .main-nav ul li {
        margin-left: 0;
        margin-bottom: 0.5rem;
        width: 100%;
    }
    .main-nav ul li a {
        display: block; /* Cho link chiếm toàn bộ chiều ngang */
        text-align: left;
    }
    .main-nav .user-info {
        margin-top: 0.5rem;
        width: 100%;
        text-align: left;
    }
    .ticket-details-header {
        flex-direction: column;
        align-items: flex-start;
    }
    .ticket-details-header .btn {
        margin-top: 0.5rem;
    }
}

@media (max-width: 576px) {
    h1 { font-size: 1.8rem; }
    h2 { font-size: 1.6rem; }
    .btn {
        font-size: 0.9rem;
        padding: 0.4rem 0.8rem;
    }
}