static/css/style.css

:root {
    /* Color System */
    --primary-color: #6B7280;
    --success-color: #10B981;
    --warning-color: #F59E0B;
    --danger-color: #EF4444;
    --white: #FFFFFF;
    
    /* Grayscale System */
    --gray-50: #F9FAFB;
    --gray-100: #F3F4F6;
    --gray-200: #E5E7EB;
    --gray-300: #D1D5DB;
    --gray-400: #6B7280;
    --gray-500: #4B5563;
    --gray-600: #374151;
    --gray-700: #1F2937;
    --gray-800: #111827;
    --gray-900: #000000;
    
    /* Layout */
    --bg-primary: #FFFFFF;
    --bg-secondary: #F9FAFB;
    --bg-card: #FFFFFF;
    --text-primary: #111827;
    --text-secondary: #374151;
    --text-muted: #6B7280;
    --border-color: #E5E7EB;
    --shadow-color: rgba(0, 0, 0, 0.1);
    
    /* Glass button styles */
    --glass-bg: rgba(255,255,255,0.2);
    --glass-border: rgba(255,255,255,0.3);
    --glass-hover-bg: rgba(255,255,255,0.3);
    --glass-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

/* Base Styles */
html, body {
    margin: 0;
    padding: 0;
}

body {
    background: 
        radial-gradient(circle at 20% 80%, rgba(135, 206, 235, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 20%, rgba(152, 251, 152, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 40% 40%, rgba(255, 218, 185, 0.1) 0%, transparent 50%),
        linear-gradient(135deg, #fef7f0 0%, #f0f4f8 100%);
    min-height: 100vh;
    font-family: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    color: var(--text-primary);
    position: relative;
    overflow-x: hidden;
}

.container-fluid {
    background: transparent;
    border-radius: 24px;
    margin: 0 20px 20px 0;
    padding: 0;
    position: relative;
    overflow: hidden;
}

/* Full height container for login/register pages */
.container-fluid.min-vh-100 {
    min-height: 100vh;
    margin: 0;
    border-radius: 0;
}

/* Header */
header {
    background: var(--gray-400);
    color: #FFFFFF;
    border-radius: 16px;
    margin: 0 0 1.5rem 0;
    padding: 1.5rem 2rem;
    position: relative;
    overflow: hidden;
}

header h1,
header .display-4,
header .text-primary {
    color: #F3F4F6 !important;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    margin: 0;
    font-weight: 700;
    letter-spacing: -0.025em;
    font-size: 2.2rem;
    position: relative;
    z-index: 1;
}

/* Hide unused elements */
header button,
header .btn,
header [class*="toggle"],
header [class*="theme"],
header [id*="toggle"],
header [id*="theme"],
.fa-moon,
.fa-sun,
[class*="dark-mode"],
[class*="theme-toggle"] {
    display: none;
    visibility: hidden;
}

header p,
header .lead {
    display: none;
}

/* Cards */
.card {
    border: 1px solid var(--border-color);
    border-radius: 20px;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    background: var(--bg-card);
    box-shadow: 0 8px 32px var(--shadow-color), 0 2px 8px rgba(0, 0, 0, 0.04);
    position: relative;
    overflow: hidden;
    margin-bottom: 2rem;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    transition: left 0.6s ease;
}

.card:hover {
    transform: translateY(-2px) scale(1.01);
    box-shadow: 0 8px 25px rgba(168, 200, 236, 0.15), 0 4px 16px rgba(0, 0, 0, 0.05);
}

.card:hover::before {
    left: 100%;
}

.card-header {
    border-radius: 20px 20px 0 0 !important;
    border: none;
    padding: 1.5rem;
    background: var(--gray-400);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    color: #FFFFFF;
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
    font-weight: 600;
}

.card-body {
    padding: 1.5rem;
}

/* Forms */
.form-control {
    border-radius: 8px;
    border: 1px solid var(--gray-300);
    padding: 0.75rem 1rem;
    font-size: 0.9rem;
    transition: all 0.2s ease;
    background: var(--white);
    color: var(--gray-900);
    position: relative;
    box-shadow: 0 2px 8px rgba(168, 200, 236, 0.05);
    min-height: 45px;
    width: 100%;
}

/* Form Layout */
#feedbackForm {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

#feedbackForm .d-grid {
    margin-bottom: 0.5rem;
}

.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(168, 200, 236, 0.1), 0 2px 8px rgba(168, 200, 236, 0.1);
    background: var(--white);
    outline: none;
    transform: none;
}

.form-control:focus + .form-label,
.form-control:not(:placeholder-shown) + .form-label {
    transform: translateY(-8px) scale(0.85);
    color: var(--primary-color);
}

.form-label {
    color: var(--gray-900) !important;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.form-text {
    color: var(--gray-700) !important;
    font-size: 0.875rem;
    margin-top: 0.25rem !important;
    margin-bottom: 0 !important;
}

/* Buttons */
.btn {
    border-radius: 12px;
    padding: 0.875rem 1.75rem;
    font-weight: 600;
    text-transform: none;
    letter-spacing: 0;
    transition: all 0.3s ease;
    border: 1px solid transparent;
    font-size: 1rem;
}

.btn-primary {
    background: var(--gray-400);
    border: 1px solid var(--gray-400);
    color: var(--white);
    font-weight: 600;
    box-shadow: 0 4px 12px rgba(107, 114, 128, 0.3);
    position: relative;
    overflow: hidden;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn-primary::before,
.btn.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.5s ease;
}

.btn-primary:hover,
.btn-primary:focus,
.btn-primary:active,
.btn-primary:not(:disabled):not(.disabled):active,
.btn-primary:not(:disabled):not(.disabled).active,
.show > .btn-primary.dropdown-toggle {
    background: var(--gray-500) !important;
    border-color: var(--gray-500) !important;
    color: var(--white) !important;
    box-shadow: 0 0 0 3px rgba(75, 85, 99, 0.25) !important;
}

/* Specific override for analyze button */
#analyzeBtn:hover,
#analyzeBtn:focus,
#analyzeBtn:active {
    background: var(--gray-500) !important;
    border-color: var(--gray-500) !important;
    color: var(--white) !important;
}

.btn-outline-secondary {
    border-color: var(--gray-500);
    color: var(--gray-700);
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-outline-secondary:hover {
    border-color: var(--gray-600);
    color: var(--white);
    background: var(--gray-500);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.btn-outline-info {
    border-color: var(--gray-500);
    color: var(--gray-700);
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-outline-info:hover {
    background: var(--gray-500);
    border-color: var(--gray-500);
    color: var(--white);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

/* Results - Removed duplicate rule */

#sentimentIcon i,
#topicIcon i {
    transition: transform 0.3s ease;
}

#sentimentIcon:hover i,
#topicIcon:hover i {
    transform: scale(1.1);
}

/* Sentiment Colors - Consistent with card headers */
.sentiment-positive { color: var(--success-color) !important; font-weight: 600; }
.sentiment-neutral { color: var(--warning-color) !important; font-weight: 600; }
.sentiment-negative { color: var(--danger-color) !important; font-weight: 600; }

/* Topic Colors - Consistent with card headers */
.topic-lecturer { color: var(--gray-800) !important; font-weight: 600; }
.topic-training_program { color: var(--gray-700) !important; font-weight: 600; }
.topic-facility { color: var(--gray-600) !important; font-weight: 600; }
.topic-others { color: var(--gray-500) !important; font-weight: 600; }

/* Cards - Unified Gray Color Scheme */
.card-header {
    background: var(--gray-400);
    color: #F3F4F6;
    border-bottom: 1px solid var(--gray-300);
}

.card-header.bg-primary {
    background: var(--gray-400) !important;
    color: #F3F4F6 !important;
}

.card-header h1,
.card-header h2,
.card-header h3,
.card-header h4,
.card-header h5,
.card-header h6,
.card-header .card-title {
    color: #F3F4F6 !important;
}

/* Button Container Spacing */
.d-flex.gap-2 {
    gap: 0.5rem;
    margin-top: 0.75rem;
}

.d-flex.gap-2 .btn {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

/* Header Buttons */
header .btn-outline-light {
    border-color: rgba(255, 255, 255, 0.5);
    color: #FFFFFF;
    font-weight: 600;
    transition: all 0.3s ease;
}

header .btn-outline-light:hover {
    background-color: rgba(255, 255, 255, 0.1);
    border-color: #FFFFFF;
    color: #FFFFFF;
    transform: translateY(-2px);
}

header .btn-light {
    background-color: rgba(255, 255, 255, 0.9);
    color: var(--gray-700);
    font-weight: 600;
    transition: all 0.3s ease;
}

header .btn-light:hover {
    background-color: #FFFFFF;
    color: var(--gray-800);
    transform: translateY(-2px);
}

/* Dropdown Menu */
.dropdown-menu {
    border-radius: 12px;
    border: 1px solid var(--gray-200);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
    margin-top: 0.5rem;
}

.dropdown-item {
    padding: 0.75rem 1rem;
    font-weight: 500;
    transition: all 0.2s ease;
}

.dropdown-item:hover {
    background-color: var(--gray-100);
    color: var(--gray-800);
}

/* Components */
.spinner-border {
    width: 3rem;
    height: 3rem;
}

.alert {
    border-radius: 4px;
    border: 1px solid var(--gray-200);
    padding: 0.5rem 0.75rem;
    background: var(--white);
    transition: opacity 0.5s ease-out, transform 0.5s ease-out;
    font-size: 0.875rem;
    margin-bottom: 0.5rem;
    max-width: 100%;
    line-height: 1.4;
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: 2.5rem;
}

.alert.fade-out {
    opacity: 0;
    transform: translateY(-10px);
}

/* Compact alert styles */
.alert .btn-close {
    padding: 0;
    margin: 0;
    width: 1rem;
    height: 1rem;
    font-size: 0.75rem;
    line-height: 1;
    position: relative;
    top: 0;
    right: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    border: none;
    background: transparent;
    opacity: 0.5;
    transition: opacity 0.15s ease-in-out;
}

.alert .btn-close:hover {
    opacity: 1;
}

.alert .btn-close::before {
    content: "×";
    font-size: 1.2rem;
    font-weight: bold;
    line-height: 1;
}

.alert i {
    margin-right: 0.5rem;
    font-size: 0.875rem;
    display: inline-flex;
    align-items: center;
    flex-shrink: 0;
}

.alert .alert-content {
    flex: 1;
    display: flex;
    align-items: center;
}

/* Alert positioning */
.alert-success {
    background-color: rgba(16, 185, 129, 0.1);
    border-color: rgba(16, 185, 129, 0.2);
    color: #065f46;
}

.alert-info {
    background-color: rgba(107, 114, 128, 0.1);
    border-color: rgba(107, 114, 128, 0.2);
    color: #374151;
}

.alert-warning {
    background-color: rgba(245, 158, 11, 0.1);
    border-color: rgba(245, 158, 11, 0.2);
    color: #92400e;
}

.alert-danger {
    background-color: rgba(239, 68, 68, 0.1);
    border-color: rgba(239, 68, 68, 0.2);
    color: #991b1b;
}

/* Specific positioning for main page alerts */
.row.justify-content-center.mb-2 {
    margin-top: 0.5rem;
}

/* Compact spacing for alerts */
.alert + .alert {
    margin-top: 0.25rem;
}

blockquote {
    border-left: 4px solid var(--primary-color);
    padding-left: 1.5rem;
    font-style: italic;
    color: var(--gray-900);
    background: var(--gray-50);
    border-radius: 0 8px 8px 0;
    margin: 0;
}

footer {
    background: var(--gray-50);
    border-radius: 0 0 16px 16px;
    margin: 0;
    border-top: 1px solid var(--gray-200);
    color: var(--gray-800);
}

/* Bootstrap Overrides */
.bg-primary {
    background: var(--gray-400);
}

.text-primary {
    color: #F3F4F6 !important;
}

.spinner-border.text-primary {
    color: #F3F4F6 !important;
}

.border-primary {
    border-color: var(--primary-color);
}

/* Ensure all Bootstrap primary elements use gray */
.btn-primary,
.card-header.bg-primary,
.alert-primary {
    background: var(--gray-400);
    border-color: var(--gray-400);
    color: #F3F4F6;
}

/* Force all primary buttons to never use blue */
.btn-primary,
.btn-primary:link,
.btn-primary:visited,
.btn-primary:hover,
.btn-primary:focus,
.btn-primary:active,
.btn-primary:not(:disabled):not(.disabled):active,
.btn-primary:not(:disabled):not(.disabled).active {
    background: var(--gray-400) !important;
    border-color: var(--gray-400) !important;
    color: #F3F4F6 !important;
}

.btn-primary:hover,
.btn-primary:focus,
.btn-primary:active {
    background: var(--gray-500) !important;
    border-color: var(--gray-500) !important;
}

/* Force all text-primary to use light gray */
.text-primary,
h1.text-primary,
h2.text-primary,
h3.text-primary,
h4.text-primary,
h5.text-primary,
h6.text-primary,
.display-4.text-primary,
.fw-bold.text-primary {
    color: #F3F4F6 !important;
}

/* Force all icons to use light gray */
.text-primary i,
.text-primary .fas,
.text-primary .fa {
    color: #F3F4F6 !important;
}

/* Badge styling - ensure proper background */
.badge {
    display: inline-block !important;
    padding: 0.375rem 0.75rem !important;
    font-size: 0.875rem !important;
    font-weight: 500 !important;
    line-height: 1 !important;
    text-align: center !important;
    white-space: nowrap !important;
    vertical-align: baseline !important;
    border-radius: 0.375rem !important;
}

.badge.bg-light {
    background-color: #f8f9fa !important;
    color: #212529 !important;
}

.badge.bg-secondary {
    background-color: #6c757d !important;
    color: #fff !important;
}

.badge.bg-dark {
    background-color: #212529 !important;
    color: #fff !important;
}

/* CSV Results table styling */
#csvResultsTable td {
    vertical-align: middle !important;
    text-align: center !important;
}

#csvResultsTable td:nth-child(2) {
    text-align: left !important;
}

#csvResultsTable td:nth-child(3) {
    text-align: left !important;
}

#csvResultsTable td:nth-child(4) {
    text-align: left !important;
}

#csvResultsTable td:last-child {
    text-align: left !important;
}

/* Feedback count badge specific styling */
#feedbackCount {
    font-weight: 700 !important;
    font-size: 1rem !important;
    vertical-align: middle !important;
    display: inline-flex !important;
    align-items: center !important;
    justify-content: center !important;
    min-width: 2.5rem !important;
    height: 1.75rem !important;
    line-height: 1 !important;
    margin-left: 0.5rem !important;
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(30px) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(50px) rotateX(10deg);
    }
    to {
        opacity: 1;
        transform: translateY(0) rotateX(0deg);
    }
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.fade-in {
    animation: fadeIn 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

#results .card {
    animation: slideInUp 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

#sentimentIcon i {
    animation: pulse 2s ease-in-out infinite;
}

#topicIcon i {
    animation: bounce 1.5s ease-in-out infinite;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--gray-100);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb {
    background: rgba(135, 206, 235, 0.6);
    border-radius: 10px;
    border: 1px solid rgba(255, 255, 255, 0.3);
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(135, 206, 235, 0.8);
}

/* Pagination Styles - Gray Theme */
.pagination {
    margin: 0;
    padding: 0;
    display: flex;
    list-style: none;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    border: 1px solid var(--gray-200);
}

.pagination .page-item {
    margin: 0;
    border-right: 1px solid var(--gray-200);
}

.pagination .page-item:last-child {
    border-right: none;
}

.pagination .page-item:first-child .page-link {
    border-top-left-radius: 8px;
    border-bottom-left-radius: 8px;
}

.pagination .page-item:last-child .page-link {
    border-top-right-radius: 8px;
    border-bottom-right-radius: 8px;
}

.pagination .page-link {
    display: block;
    padding: 0.5rem 0.75rem;
    text-decoration: none;
    color: var(--gray-700);
    background-color: var(--white);
    border: none;
    font-weight: 500;
    font-size: 0.9rem;
    transition: all 0.2s ease;
    min-width: 40px;
    text-align: center;
}

.pagination .page-link:hover {
    color: var(--white);
    background-color: var(--gray-500);
    text-decoration: none;
}

.pagination .page-item.active .page-link {
    color: var(--white);
    background-color: var(--gray-400);
    font-weight: 600;
}

.pagination .page-item.active .page-link:hover {
    background-color: var(--gray-500);
}

.pagination .page-item.disabled .page-link {
    color: var(--gray-400);
    background-color: var(--gray-100);
    cursor: not-allowed;
}

.pagination .page-item.disabled .page-link:hover {
    color: var(--gray-400);
    background-color: var(--gray-100);
}

/* Navigation Links */
a[href*="login"]:hover,
a[href*="register"]:hover {
    color: var(--gray-300);
    text-decoration: underline;
    transform: translateY(-1px);
    transition: all 0.3s ease;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container-fluid { 
        margin: 0 10px 10px 0; 
    }
    
    header { 
        border-radius: 12px; 
        padding: 1rem; 
        margin: 0 0 1rem 0; 
    }
    
    header h1 { 
        font-size: 1.8rem; 
    }
    
    .card-body { 
        padding: 1.25rem; 
    }
    
    .btn { 
        padding: 0.75rem 1.5rem; 
        font-size: 0.95rem;
    }
    
    .card-header { 
        border-radius: 12px 12px 0 0; 
        padding: 1rem;
    }
    
    .form-control {
        padding: 0.875rem 1rem;
        min-height: 100px;
    }
    
    .d-flex.gap-2 .btn {
        padding: 0.4rem 0.8rem;
        font-size: 0.85rem;
    }
    
    .pagination .page-link {
        padding: 0.4rem 0.6rem;
        font-size: 0.85rem;
        min-width: 35px;
    }
}

/* Glass Button Component */
.btn-glass {
    background-color: var(--glass-bg);
    border: 1px solid var(--glass-border);
    color: #fff;
    padding: 8px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    gap: 6px;
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.btn-glass:hover {
    background-color: var(--glass-hover-bg);
    transform: translateY(-2px);
    box-shadow: var(--glass-shadow);
    color: #fff;
}

/* Link hover effects for login/register pages */
a.text-secondary.fw-bold:hover {
    color: #3B82F6 !important;
    transition: color 0.3s ease;
}

.btn-glass:active {
    transform: translateY(0);
    box-shadow: none;
}

.custom-alert-left {
    justify-content: flex-start !important; /* ép icon + text về trái */
    text-align: left !important;
    width: 100% !important;
    margin-left: 0 !important;
}

.custom-alert-left i {
    margin-left: 0 !important; /* icon sát trái */
}

/* Multiple Topics Display Styles */
.multiple-topics-container {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.topic-sentiment-item {
    background: var(--gray-100);
    border-radius: 12px;
    padding: 1rem;
    border-left: 4px solid var(--gray-400);
    transition: all 0.3s ease;
}

.topic-sentiment-item:hover {
    background: var(--gray-200);
    transform: translateX(4px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.topic-sentiment-item .fw-semibold {
    color: var(--text-primary);
    font-size: 1.05rem;
}