/* Design Tokens & CSS Variables */
:root {
    --bg-dark: #090d16;
    --bg-card: #131b2e;
    --bg-input: #1c273e;
    --border-color: rgba(255, 255, 255, 0.08);
    --border-focus: #6366f1;

    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --text-subtle: #64748b;

    --primary: #6366f1;
    --primary-hover: #4f46e5;
    
    --success: #10b981;
    --success-bg: rgba(16, 185, 129, 0.15);
    --success-border: rgba(16, 185, 129, 0.3);

    --danger: #ef4444;
    --danger-bg: rgba(239, 68, 68, 0.15);
    --danger-border: rgba(239, 68, 68, 0.3);

    --warning: #f59e0b;
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 20px;

    --shadow-glow: 0 0 25px rgba(99, 102, 241, 0.2);
    --shadow-card: 0 10px 30px rgba(0, 0, 0, 0.4);
    --font-main: 'Inter', sans-serif;
    --font-heading: 'Outfit', sans-serif;
}

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

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    font-family: var(--font-main);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    padding: 20px;
    background-image: 
        radial-gradient(circle at 15% 15%, rgba(99, 102, 241, 0.12) 0%, transparent 40%),
        radial-gradient(circle at 85% 85%, rgba(16, 185, 129, 0.08) 0%, transparent 40%);
}

.app-container {
    width: 100%;
    max-width: 1200px;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

/* Header */
.app-header {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 16px 24px;
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    box-shadow: var(--shadow-card);
}

.brand {
    display: flex;
    align-items: center;
    gap: 16px;
}

.brand-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-sm);
    background: linear-gradient(135deg, #6366f1, #4f46e5);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: #fff;
    box-shadow: var(--shadow-glow);
}

.brand-text h1 {
    font-family: var(--font-heading);
    font-size: 22px;
    font-weight: 700;
    letter-spacing: -0.5px;
    background: linear-gradient(90deg, #ffffff, #cbd5e1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.sub-title {
    font-size: 13px;
    color: var(--text-muted);
}

/* Connection Controls */
.connection-box {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.input-wrapper {
    position: relative;
    display: flex;
    align-items: center;
}

.input-icon {
    position: absolute;
    left: 12px;
    color: var(--text-subtle);
    font-size: 14px;
}

#backendUrl {
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: 10px 12px 10px 34px;
    color: var(--text-main);
    font-size: 13px;
    width: 240px;
    outline: none;
    transition: all 0.2s;
}

#backendUrl:focus {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
}

.status-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.status-badge .dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
}

.status-online {
    background: var(--success-bg);
    color: var(--success);
    border: 1px solid var(--success-border);
}

.status-online .dot {
    background: var(--success);
    box-shadow: 0 0 8px var(--success);
}

.status-offline {
    background: var(--danger-bg);
    color: var(--danger);
    border: 1px solid var(--danger-border);
}

.status-offline .dot {
    background: var(--danger);
}

/* Main Layout Grid */
.main-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

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

.card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px;
    box-shadow: var(--shadow-card);
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.card-title {
    font-family: var(--font-heading);
    font-size: 18px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-main);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 12px;
}

/* Form Controls */
.form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.form-group label {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-muted);
    display: flex;
    align-items: center;
    gap: 6px;
}

.select-wrapper {
    position: relative;
}

select {
    width: 100%;
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    color: var(--text-main);
    font-size: 14px;
    appearance: none;
    outline: none;
    cursor: pointer;
    transition: all 0.2s;
}

select:focus {
    border-color: var(--border-focus);
}

.select-icon {
    position: absolute;
    right: 16px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-subtle);
    pointer-events: none;
}

/* Drop Zone */
.drop-zone {
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-sm);
    padding: 30px 20px;
    text-align: center;
    background: rgba(255, 255, 255, 0.02);
    position: relative;
    cursor: pointer;
    transition: all 0.2s ease;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.drop-zone:hover, .drop-zone.drag-over {
    border-color: var(--primary);
    background: rgba(99, 102, 241, 0.05);
}

.file-input {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
}

.upload-icon {
    font-size: 36px;
    color: var(--primary);
    margin-bottom: 12px;
}

.drop-text {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-main);
}

.browse-text {
    font-size: 13px;
    color: var(--text-muted);
    margin-top: 4px;
}

.highlight {
    color: var(--primary);
    font-weight: 600;
}

.file-limits {
    display: block;
    font-size: 11px;
    color: var(--text-subtle);
    margin-top: 8px;
}

.image-preview-container {
    position: relative;
    width: 100%;
    max-height: 240px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.image-preview-container img {
    max-width: 100%;
    max-height: 220px;
    border-radius: var(--radius-sm);
    object-fit: contain;
}

.btn-remove {
    position: absolute;
    top: 6px;
    right: 6px;
    background: rgba(0, 0, 0, 0.7);
    color: #fff;
    border: none;
    border-radius: 50%;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background 0.2s;
}

.btn-remove:hover {
    background: var(--danger);
}

/* Buttons */
.btn {
    padding: 12px 20px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    transition: all 0.2s;
}

.btn-primary {
    background: linear-gradient(135deg, #6366f1, #4f46e5);
    color: #fff;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover:not(:disabled) {
    background: linear-gradient(135deg, #4f46e5, #4338ca);
    transform: translateY(-1px);
}

.btn-primary:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    box-shadow: none;
}

.btn-secondary {
    background: var(--bg-input);
    color: var(--text-main);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.08);
}

.btn-block {
    width: 100%;
}

/* Results Section */
.empty-state {
    text-align: center;
    padding: 40px 20px;
    color: var(--text-muted);
}

.empty-icon {
    font-size: 48px;
    color: var(--text-subtle);
    margin-bottom: 16px;
    opacity: 0.6;
}

.empty-state h3 {
    font-size: 16px;
    color: var(--text-main);
    margin-bottom: 8px;
}

.empty-state p {
    font-size: 13px;
    max-width: 320px;
    margin: 0 auto;
}

/* Badge & Metrics */
.badge-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border-color);
}

.result-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 18px;
    border-radius: 30px;
    font-size: 15px;
    font-weight: 700;
    letter-spacing: 0.5px;
}

.badge-original {
    background: var(--success-bg);
    color: var(--success);
    border: 1px solid var(--success-border);
}

.badge-fake {
    background: var(--danger-bg);
    color: var(--danger);
    border: 1px solid var(--danger-border);
}

.meta-doc {
    font-size: 13px;
    color: var(--text-muted);
}

.metric-box {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.metric-header {
    display: flex;
    justify-content: space-between;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-muted);
}

.confidence-val {
    color: var(--text-main);
    font-weight: 700;
}

.progress-bar-bg {
    height: 10px;
    background: var(--bg-input);
    border-radius: 5px;
    overflow: hidden;
}

.progress-bar-fill {
    height: 100%;
    background: linear-gradient(90deg, #6366f1, #10b981);
    border-radius: 5px;
    transition: width 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Gemini Section */
.gemini-section {
    background: rgba(99, 102, 241, 0.06);
    border: 1px solid rgba(99, 102, 241, 0.2);
    border-radius: var(--radius-sm);
    padding: 16px;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.gemini-header {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--primary);
    font-size: 14px;
}

.gemini-header h3 {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-main);
}

.gemini-explanation {
    font-size: 13px;
    line-height: 1.7;
    color: #cbd5e1;
    white-space: pre-wrap;
}

/* Alert Boxes */
.alert {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 14px;
    border-radius: var(--radius-sm);
    font-size: 13px;
}

.alert-danger {
    background: var(--danger-bg);
    border: 1px solid var(--danger-border);
    color: #fca5a5;
}

.alert-icon {
    font-size: 18px;
    color: var(--danger);
    margin-top: 2px;
}

.alert-content h4 {
    font-weight: 600;
    color: var(--danger);
    margin-bottom: 2px;
}

/* Utilities */
.hidden {
    display: none !important;
}

.spinner {
    width: 18px;
    height: 18px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: #fff;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.app-footer {
    text-align: center;
    padding: 16px;
    font-size: 12px;
    color: var(--text-subtle);
}