/* ============================================
   AI Article Writer - Aurora UI Gradient Style
   Premium Design System - Multi-Page Layout
   ============================================ */

/* CSS Variables */
:root {
    --aurora-1: #ff6b6b;
    --aurora-2: #4ecdc4;
    --aurora-3: #45b7d1;
    --aurora-4: #96ceb4;
    --aurora-5: #ffeaa7;
    --aurora-6: #dfe6e9;
    --aurora-7: #a29bfe;
    --aurora-8: #fd79a8;

    --gradient-primary: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #a855f7 100%);
    --gradient-aurora: linear-gradient(135deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4);
    --gradient-accent: linear-gradient(135deg, #f59e0b 0%, #ef4444 100%);

    --bg-primary: #0c0c1d;
    --bg-secondary: #131328;
    --bg-card: rgba(255, 255, 255, 0.08);
    --bg-card-hover: rgba(255, 255, 255, 0.12);

    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.85);
    --text-muted: rgba(255, 255, 255, 0.6);
    --text-hint: rgba(255, 255, 255, 0.4);

    --glass-bg: rgba(255, 255, 255, 0.06);
    --glass-border: rgba(255, 255, 255, 0.12);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);

    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --radius-xl: 20px;
    --radius-full: 9999px;

    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* Reset & Base */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    font-size: 15px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    line-height: 1.6;
}

/* Aurora Background */
.aurora-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
}

.aurora {
    position: absolute;
    width: 120%;
    height: 120%;
    border-radius: 50%;
    filter: blur(120px);
    opacity: 0.3;
    animation: aurora-float 25s ease-in-out infinite;
}

.aurora-1 { top: -40%; left: -20%; background: radial-gradient(circle, rgba(99, 102, 241, 0.4) 0%, transparent 70%); animation-delay: 0s; }
.aurora-2 { top: -20%; right: -20%; background: radial-gradient(circle, rgba(139, 92, 246, 0.3) 0%, transparent 70%); animation-delay: -6s; }
.aurora-3 { bottom: -20%; left: -20%; background: radial-gradient(circle, rgba(168, 85, 247, 0.25) 0%, transparent 70%); animation-delay: -12s; }
.aurora-4 { bottom: -40%; right: -20%; background: radial-gradient(circle, rgba(236, 72, 153, 0.2) 0%, transparent 70%); animation-delay: -18s; }

@keyframes aurora-float {
    0%, 100% { transform: translate(0, 0) rotate(0deg) scale(1); }
    25% { transform: translate(3%, 3%) rotate(90deg) scale(1.05); }
    50% { transform: translate(-3%, 6%) rotate(180deg) scale(1); }
    75% { transform: translate(5%, -3%) rotate(270deg) scale(1.05); }
}

#particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 1;
}

/* Navigation */
.nav-glass {
    position: fixed;
    top: var(--spacing-md);
    left: 50%;
    transform: translateX(-50%);
    z-index: 100;
    background: rgba(20, 20, 40, 0.8);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-sm) var(--spacing-lg);
    box-shadow: var(--glass-shadow);
}

.nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-2xl);
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.logo-icon {
    width: 36px;
    height: 36px;
    background: var(--gradient-primary);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    transition: transform var(--transition-normal);
}

.logo-icon:hover { transform: rotate(15deg) scale(1.1); }
.logo-icon svg { width: 20px; height: 20px; }
.logo-icon.small { width: 28px; height: 28px; }
.logo-icon.small svg { width: 16px; height: 16px; }

.logo-text {
    font-size: 1rem;
    font-weight: 700;
    background: linear-gradient(135deg, #fff 0%, #c4b5fd 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    gap: var(--spacing-lg);
}

.nav-link {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 0.8rem;
    font-weight: 500;
    transition: color var(--transition-fast);
}

.nav-link:hover { color: var(--text-primary); }

/* Main Container */
.main-container {
    position: relative;
    z-index: 2;
    min-height: 100vh;
    padding-top: 80px;
}

/* Page System */
.page {
    display: none;
    min-height: calc(100vh - 160px);
    padding: var(--spacing-lg);
    animation: fadeIn 0.4s ease;
}

.page.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Hero Section (Page 0) */
.hero {
    min-height: calc(100vh - 200px);
    display: flex;
    align-items: center;
    justify-content: center;
}

.hero-content {
    max-width: 720px;
    width: 100%;
    text-align: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    background: rgba(99, 102, 241, 0.15);
    border: 1px solid rgba(99, 102, 241, 0.3);
    border-radius: var(--radius-full);
    padding: var(--spacing-xs) var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    animation: fadeInUp 0.6s ease;
}

.badge-dot {
    width: 6px;
    height: 6px;
    background: #4ade80;
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

.hero-badge span:last-child {
    color: var(--text-secondary);
    font-size: 0.75rem;
    font-weight: 500;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    color: var(--text-primary);
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
}

.gradient-text {
    background: linear-gradient(135deg, #818cf8 0%, #c084fc 50%, #f472b6 100%);
    background-size: 200% auto;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradient-shift 5s ease-in-out infinite;
}

@keyframes gradient-shift {
    0%, 100% { background-position: 0% center; }
    50% { background-position: 100% center; }
}

.hero-subtitle {
    font-size: 0.95rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-2xl);
    line-height: 1.7;
}

/* Input Card */
.input-card {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
}

.input-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-sm);
}

.input-label {
    color: var(--text-primary);
    font-weight: 600;
    font-size: 0.8rem;
}

.input-wrapper {
    position: relative;
    margin-bottom: var(--spacing-md);
}

.topic-input {
    width: 100%;
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    color: var(--text-primary);
    font-size: 0.9rem;
    outline: none;
    transition: all var(--transition-normal);
}

.topic-input::placeholder { color: var(--text-hint); }
.topic-input:focus {
    border-color: rgba(99, 102, 241, 0.6);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

.input-glow {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    height: 100%;
    background: var(--gradient-primary);
    border-radius: var(--radius-md);
    filter: blur(50px);
    opacity: 0;
    transition: opacity var(--transition-normal);
    pointer-events: none;
}

.topic-input:focus + .input-glow { opacity: 0.15; }

/* Options Grid */
.options-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.option-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.option-label {
    color: var(--text-muted);
    font-size: 0.75rem;
    font-weight: 500;
    margin-bottom: var(--spacing-xs);
}

.length-options {
    display: flex;
    gap: var(--spacing-sm);
}

.length-btn {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2px;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm) var(--spacing-md);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.length-btn:hover {
    background: rgba(255, 255, 255, 0.06);
    border-color: rgba(255, 255, 255, 0.2);
}

.length-btn.active {
    background: rgba(99, 102, 241, 0.15);
    border-color: rgba(99, 102, 241, 0.5);
}

.length-icon { font-size: 1.2rem; }
.length-text { color: var(--text-primary); font-size: 0.8rem; font-weight: 600; }
.length-desc { color: var(--text-hint); font-size: 0.65rem; }

.audience-select {
    width: 100%;
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--text-primary);
    font-size: 0.8rem;
    outline: none;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.audience-select:focus { border-color: rgba(99, 102, 241, 0.6); }
.audience-select option { background: #1a1a2e; color: var(--text-primary); }

/* Start Button */
.start-btn {
    position: relative;
    width: 100%;
    background: var(--gradient-primary);
    border: none;
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    cursor: pointer;
    overflow: hidden;
    transition: all var(--transition-normal);
}

.start-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(99, 102, 241, 0.35);
}

.btn-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    color: #fff;
    font-size: 0.95rem;
    font-weight: 600;
    position: relative;
    z-index: 1;
}

.btn-icon { width: 18px; height: 18px; }

.btn-shine {
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.25), transparent);
    transition: left 0.5s ease;
}

.start-btn:hover .btn-shine { left: 100%; }

/* Features Section */
.features-section {
    padding: var(--spacing-3xl) var(--spacing-lg);
}

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

.section-title {
    font-size: clamp(1.4rem, 3vw, 1.8rem);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xl);
}

.section-title.centered { text-align: center; }

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.feature-card {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    transition: all var(--transition-normal);
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: rgba(99, 102, 241, 0.3);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
}

.feature-card.highlight {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.08), rgba(139, 92, 246, 0.08));
    border-color: rgba(99, 102, 241, 0.25);
}

.feature-icon { font-size: 2rem; margin-bottom: var(--spacing-md); }
.feature-title { color: var(--text-primary); font-size: 1rem; font-weight: 600; margin-bottom: var(--spacing-xs); }
.feature-desc { color: var(--text-muted); font-size: 0.85rem; line-height: 1.6; }

/* Page Header */
.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-lg);
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    margin-bottom: var(--spacing-xl);
    flex-wrap: wrap;
}

.back-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-xs) var(--spacing-md);
    color: var(--text-muted);
    font-size: 0.8rem;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.back-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
}

.back-btn svg { width: 16px; height: 16px; }

.page-title-group {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.page-badge {
    background: var(--gradient-primary);
    padding: 3px var(--spacing-sm);
    border-radius: var(--radius-full);
    color: #fff;
    font-size: 0.65rem;
    font-weight: 600;
}

.page-badge.success {
    background: linear-gradient(135deg, #22c55e, #16a34a);
}

.page-title {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-primary);
}

.page-status {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
    background: rgba(251, 191, 36, 0.15);
    border-radius: var(--radius-full);
}

.page-status.success {
    background: rgba(74, 222, 128, 0.15);
}

.status-dot {
    width: 6px;
    height: 6px;
    background: #fbbf24;
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

.page-status.success .status-dot {
    background: #4ade80;
}

.page-status span:last-child {
    color: var(--text-secondary);
    font-size: 0.75rem;
    font-weight: 500;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* Page Content */
.page-content {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    min-height: 300px;
    max-width: 900px;
    margin: 0 auto;
}

/* Page Actions */
.page-actions {
    display: flex;
    justify-content: flex-end;
    gap: var(--spacing-md);
    margin-top: var(--spacing-xl);
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.action-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-md);
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.action-btn svg { width: 16px; height: 16px; }

.action-btn.primary {
    background: var(--gradient-primary);
    border: none;
    color: #fff;
}

.action-btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(99, 102, 241, 0.35);
}

.action-btn.secondary {
    background: transparent;
    border: 1px solid var(--glass-border);
    color: var(--text-muted);
}

.action-btn.secondary:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
}

/* Detail Sections */
.detail-section {
    margin-bottom: var(--spacing-lg);
}

.detail-section-title {
    color: var(--text-secondary);
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.detail-text {
    color: var(--text-muted);
    font-size: 0.85rem;
    line-height: 1.7;
}

.result-list {
    list-style: none;
    color: var(--text-muted);
    font-size: 0.85rem;
}

.result-list li {
    padding: var(--spacing-xs) 0;
    padding-left: var(--spacing-lg);
    position: relative;
}

.result-list li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: #6366f1;
}

.result-box {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.result-box.success {
    border-color: rgba(74, 222, 128, 0.25);
    background: rgba(74, 222, 128, 0.05);
}

.result-box.info {
    border-color: rgba(96, 165, 250, 0.25);
    background: rgba(96, 165, 250, 0.05);
}

.result-box.warning {
    border-color: rgba(251, 191, 36, 0.25);
    background: rgba(251, 191, 36, 0.05);
}

.result-title {
    color: var(--text-primary);
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: var(--spacing-xs);
}

/* Detail Content Scrollable */
.detail-content {
    max-height: 400px;
    overflow-y: auto;
    padding-right: var(--spacing-sm);
}

.detail-content::-webkit-scrollbar { width: 4px; }
.detail-content::-webkit-scrollbar-track { background: rgba(255, 255, 255, 0.05); border-radius: 2px; }
.detail-content::-webkit-scrollbar-thumb { background: rgba(255, 255, 255, 0.15); border-radius: 2px; }

/* Code Block */
.detail-code {
    background: rgba(0, 0, 0, 0.3);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.75rem;
    color: var(--text-secondary);
    white-space: pre-wrap;
    word-break: break-word;
}

/* ==================== Research Content Styles ==================== */

/* Research Source Card */
.research-source {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-md);
    overflow: hidden;
}

.source-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: rgba(255, 255, 255, 0.03);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.source-badge {
    font-size: 0.65rem;
    font-weight: 600;
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.source-badge.web {
    background: rgba(99, 102, 241, 0.2);
    color: #a5b4fc;
}

.source-badge.wechat {
    background: rgba(37, 211, 102, 0.2);
    color: #6ee7b7;
}

.source-badge.xiaohongshu {
    background: rgba(251, 113, 133, 0.2);
    color: #fda4af;
}

.source-title {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-primary);
}

.source-content {
    padding: var(--spacing-md);
}

.source-url {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    padding: var(--spacing-xs) var(--spacing-sm);
    background: rgba(255, 255, 255, 0.03);
    border-radius: var(--radius-sm);
}

.url-label {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.url-link {
    font-size: 0.75rem;
    color: #60a5fa;
    text-decoration: none;
    word-break: break-all;
}

.url-link:hover {
    color: #93c5fd;
    text-decoration: underline;
}

.url-text {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.source-detail {
    margin-top: var(--spacing-sm);
    padding: var(--spacing-sm);
    background: rgba(0, 0, 0, 0.15);
    border-radius: var(--radius-sm);
}

.source-detail strong {
    display: block;
    color: var(--text-primary);
    font-size: 0.8rem;
    margin-bottom: var(--spacing-xs);
}

.source-detail p {
    margin-bottom: var(--spacing-xs);
    color: var(--text-muted);
    font-size: 0.75rem;
    line-height: 1.7;
}

.source-content p {
    margin-bottom: var(--spacing-xs);
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.source-content ul {
    list-style: none;
    margin: var(--spacing-sm) 0;
}

.source-content ul li {
    position: relative;
    padding-left: var(--spacing-md);
    margin-bottom: var(--spacing-xs);
    color: var(--text-muted);
    font-size: 0.8rem;
    line-height: 1.6;
}

.source-content ul li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: #6366f1;
}

.source-quote {
    margin-top: var(--spacing-sm);
    padding: var(--spacing-sm);
    background: rgba(99, 102, 241, 0.08);
    border-left: 3px solid #6366f1;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    font-style: italic;
    color: var(--text-secondary);
    font-size: 0.8rem;
}

/* Concept Card */
.concept-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
}

.concept-card h5 {
    color: var(--text-primary);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-xs);
}

.concept-desc {
    color: var(--text-muted);
    font-size: 0.8rem;
    line-height: 1.7;
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-md);
    margin-top: var(--spacing-sm);
}

.stat-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    text-align: center;
}

.stat-value {
    font-size: 1.8rem;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1.2;
}

.stat-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: var(--spacing-xs);
}

.stat-label-en {
    font-size: 0.65rem;
    color: var(--text-hint);
}

/* Scenario List */
.scenario-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.scenario-item {
    display: flex;
    gap: var(--spacing-md);
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
}

.scenario-num {
    font-size: 1.2rem;
    font-weight: 700;
    color: #6366f1;
    min-width: 2rem;
}

.scenario-content h5 {
    color: var(--text-primary);
    font-size: 0.9rem;
    margin-bottom: var(--spacing-xs);
}

.scenario-content p {
    color: var(--text-muted);
    font-size: 0.8rem;
}

/* Credibility Grid */
.credibility-grid {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.cred-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.cred-label {
    min-width: 140px;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.cred-bar {
    flex: 1;
    height: 8px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 4px;
    overflow: hidden;
}

.cred-fill {
    height: 100%;
    background: linear-gradient(90deg, #6366f1, #8b5cf6);
    border-radius: 4px;
    transition: width 0.5s ease;
}

.cred-bar.green .cred-fill {
    background: linear-gradient(90deg, #10b981, #34d399);
}

.cred-score {
    min-width: 40px;
    text-align: right;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.cred-score.highlight {
    color: #4ade80;
    font-weight: 600;
}

/* Confirm Box */
.confirm-box {
    background: rgba(99, 102, 241, 0.08);
    border: 1px solid rgba(99, 102, 241, 0.2);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
}

.confirm-box p {
    margin-bottom: var(--spacing-xs);
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.confirm-question {
    margin-top: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
    font-weight: 500;
}

/* Feedback Section */
.feedback-section {
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-md);
    border-top: 1px dashed rgba(255, 255, 255, 0.2);
}

.feedback-label {
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
}

/* Adjustment Notice */
.adjustment-notice {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    padding: var(--spacing-md);
    background: rgba(251, 191, 36, 0.1);
    border: 1px solid rgba(251, 191, 36, 0.3);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
}

.adjustment-icon {
    font-size: 1.2rem;
    line-height: 1;
}

.adjustment-text {
    font-size: 0.8rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

.adjustment-text em {
    color: #fbbf24;
    font-style: italic;
}

/* Updated Badge */
.updated-badge {
    display: inline-block;
    padding: 2px 8px;
    background: linear-gradient(135deg, #10b981, #34d399);
    border-radius: var(--radius-sm);
    font-size: 0.65rem;
    font-weight: 600;
    color: white;
    margin-left: var(--spacing-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Source Detail Expanded */
.source-detail {
    margin-top: var(--spacing-sm);
    padding: var(--spacing-sm);
    background: rgba(0, 0, 0, 0.2);
    border-radius: var(--radius-sm);
}

.source-detail p {
    margin-bottom: var(--spacing-xs);
    color: var(--text-muted);
    font-size: 0.75rem;
    line-height: 1.7;
}

.source-detail strong {
    color: var(--text-secondary);
}

.feedback-input {
    width: 100%;
    min-height: 100px;
    padding: var(--spacing-md);
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 0.85rem;
    font-family: 'Inter', sans-serif;
    resize: vertical;
    line-height: 1.6;
}

.feedback-input:focus {
    outline: none;
    border-color: #6366f1;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.3);
}

.feedback-input::placeholder {
    color: var(--text-hint);
}

.feedback-submit-btn {
    margin-top: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    background: linear-gradient(135deg, #6366f1, #8b5cf6);
    border: none;
    border-radius: var(--radius-md);
    color: white;
    font-size: 0.8rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.feedback-submit-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.feedback-submit-btn:active {
    transform: translateY(0);
}

/* Responsive */
@media (max-width: 768px) {
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .cred-item {
        flex-wrap: wrap;
    }

    .cred-label {
        min-width: 100%;
    }

    .cred-bar {
        order: 3;
    }
}

/* Footer */
.footer {
    position: relative;
    padding: var(--spacing-xl) var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    z-index: 2;
}

.footer-content {
    max-width: 500px;
    margin: 0 auto;
    text-align: center;
}

.footer-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
    font-weight: 600;
    font-size: 0.9rem;
}

.footer-text { color: var(--text-muted); font-size: 0.8rem; margin-bottom: var(--spacing-xs); }
.footer-copyright { color: var(--text-hint); font-size: 0.7rem; }

/* Toast */
#toastContainer {
    position: fixed;
    bottom: var(--spacing-lg);
    right: var(--spacing-lg);
    z-index: 1000;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.toast {
    background: rgba(30, 30, 50, 0.95);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--text-primary);
    font-size: 0.8rem;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    animation: slideIn 0.3s ease;
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

.toast.success { border-color: rgba(74, 222, 128, 0.3); }
.toast.success::before { content: '✓'; color: #4ade80; font-weight: bold; }
.toast.error { border-color: rgba(248, 113, 113, 0.3); }
.toast.error::before { content: '✕'; color: #f87171; font-weight: bold; }

@keyframes slideIn {
    from { opacity: 0; transform: translateX(100%); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(15px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Responsive */
@media (max-width: 768px) {
    html { font-size: 14px; }
    .nav-links { display: none; }
    .options-grid { grid-template-columns: 1fr; }
    .page-header { flex-direction: column; align-items: flex-start; }
    .page-actions { flex-direction: column; }
    .action-btn { width: 100%; justify-content: center; }
    .hero-title { font-size: 1.8rem; }
}

@media (max-width: 480px) {
    .hero-title { font-size: 1.5rem; }
    .length-options { flex-direction: column; }
}

/* ==================== Multi-Page Layout ==================== */
.main-container {
    position: relative;
    z-index: 2;
    min-height: 100vh;
    padding-top: 80px;
}

.page {
    display: none;
    min-height: 100vh;
    padding: var(--spacing-xl) var(--spacing-lg);
    max-width: 1200px;
    margin: 0 auto;
    animation: fadeInUp 0.5s ease;
}

.page.active {
    display: block;
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.back-btn {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    background: transparent;
    border: 1px solid var(--glass-border);
    color: var(--text-muted);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    cursor: pointer;
    font-size: 0.85rem;
    transition: all var(--transition-normal);
}

.back-btn:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
}

.back-btn svg { width: 16px; height: 16px; }

.page-title-group {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.page-badge {
    background: var(--gradient-primary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-full);
    color: #fff;
    font-size: 0.7rem;
    font-weight: 600;
}

.page-badge.success {
    background: linear-gradient(135deg, #4ade80, #22c55e);
}

.page-title {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-primary);
    margin: 0;
}

.page-status {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
    background: rgba(251, 191, 36, 0.15);
    border-radius: var(--radius-full);
}

.page-status.success {
    background: rgba(74, 222, 128, 0.15);
}

.page-status .status-dot {
    width: 8px;
    height: 8px;
    background: #fbbf24;
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

.page-status.success .status-dot {
    background: #4ade80;
}

.page-status span:last-child {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.page-content {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    min-height: 400px;
}

.page-actions {
    display: flex;
    justify-content: flex-end;
    gap: var(--spacing-md);
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.action-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: var(--radius-md);
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    border: none;
}

.action-btn svg { width: 16px; height: 16px; }

.action-btn.primary {
    background: var(--gradient-primary);
    color: #fff;
}

.action-btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(99, 102, 241, 0.35);
}

.action-btn.secondary {
    background: transparent;
    border: 1px solid var(--glass-border);
    color: var(--text-muted);
}

.action-btn.secondary:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
}

/* Hero Section */
.hero {
    position: relative;
    min-height: 80vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-2xl) var(--spacing-lg);
}

.hero-content {
    max-width: 720px;
    width: 100%;
    text-align: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    background: rgba(99, 102, 241, 0.15);
    border: 1px solid rgba(99, 102, 241, 0.3);
    border-radius: var(--radius-full);
    padding: var(--spacing-xs) var(--spacing-md);
    margin-bottom: var(--spacing-lg);
    animation: fadeInUp 0.6s ease;
}

.badge-dot {
    width: 6px;
    height: 6px;
    background: #4ade80;
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

.hero-badge span:last-child {
    color: var(--text-secondary);
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: 0.5px;
}

.hero-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    color: var(--text-primary);
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    animation: fadeInUp 0.6s ease 0.1s both;
}

.hero-subtitle {
    font-size: 0.95rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-2xl);
    line-height: 1.7;
    animation: fadeInUp 0.6s ease 0.2s both;
}

/* Input Card */
.input-card {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    animation: fadeInUp 0.6s ease 0.3s both;
}

.input-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-sm);
}

.input-label {
    color: var(--text-primary);
    font-weight: 600;
    font-size: 0.8rem;
}

.input-wrapper {
    position: relative;
    margin-bottom: var(--spacing-md);
}

.topic-input {
    width: 100%;
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    color: var(--text-primary);
    font-size: 0.9rem;
    outline: none;
    transition: all var(--transition-normal);
}

.topic-input::placeholder { color: var(--text-hint); }
.topic-input:focus {
    border-color: rgba(99, 102, 241, 0.6);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

.input-glow {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    height: 100%;
    background: var(--gradient-primary);
    border-radius: var(--radius-md);
    filter: blur(50px);
    opacity: 0;
    transition: opacity var(--transition-normal);
    pointer-events: none;
}

.topic-input:focus + .input-glow { opacity: 0.15; }

/* Options Grid */
.options-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.option-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.option-label {
    color: var(--text-muted);
    font-size: 0.75rem;
    font-weight: 500;
    margin-bottom: var(--spacing-xs);
}

.length-options {
    display: flex;
    gap: var(--spacing-sm);
}

.length-btn {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2px;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm) var(--spacing-md);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.length-btn:hover {
    background: rgba(255, 255, 255, 0.06);
    border-color: rgba(255, 255, 255, 0.2);
}

.length-btn.active {
    background: rgba(99, 102, 241, 0.15);
    border-color: rgba(99, 102, 241, 0.5);
}

.length-icon { font-size: 1.2rem; }
.length-text { color: var(--text-primary); font-size: 0.8rem; font-weight: 600; }
.length-desc { color: var(--text-hint); font-size: 0.65rem; }

.audience-select {
    width: 100%;
    background: rgba(0, 0, 0, 0.4);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--text-primary);
    font-size: 0.8rem;
    outline: none;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.audience-select:focus { border-color: rgba(99, 102, 241, 0.6); }
.audience-select option { background: #1a1a2e; color: var(--text-primary); }

/* Start Button */
.start-btn {
    position: relative;
    width: 100%;
    background: var(--gradient-primary);
    border: none;
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    cursor: pointer;
    overflow: hidden;
    transition: all var(--transition-normal);
}

.start-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(99, 102, 241, 0.35);
}

.btn-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    color: #fff;
    font-size: 0.95rem;
    font-weight: 600;
    position: relative;
    z-index: 1;
}

.btn-icon { width: 18px; height: 18px; }

.btn-shine {
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.25), transparent);
    transition: left 0.5s ease;
}

.start-btn:hover .btn-shine { left: 100%; }

/* Features Section */
.features-section {
    padding: var(--spacing-3xl) var(--spacing-lg);
}

.features-container {
    max-width: 1000px;
    margin: 0 auto;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.feature-card {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    transition: all var(--transition-normal);
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: rgba(99, 102, 241, 0.3);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
}

.feature-card.highlight {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.08), rgba(139, 92, 246, 0.08));
    border-color: rgba(99, 102, 241, 0.25);
}

.feature-icon { font-size: 1.8rem; margin-bottom: var(--spacing-md); }
.feature-title { color: var(--text-primary); font-size: 0.95rem; font-weight: 600; margin-bottom: var(--spacing-xs); }
.feature-desc { color: var(--text-muted); font-size: 0.8rem; line-height: 1.6; }

/* ============================================
   Test Panel Styles (Development Only)
   ============================================ */
.test-panel {
    margin-top: 2rem;
    background: linear-gradient(135deg, rgba(245, 158, 11, 0.1), rgba(239, 68, 68, 0.1));
    border: 1px dashed rgba(245, 158, 11, 0.4);
    border-radius: var(--radius-lg);
    overflow: hidden;
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.test-panel-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1rem;
    background: rgba(245, 158, 11, 0.15);
    border-bottom: 1px dashed rgba(245, 158, 11, 0.3);
    font-size: 0.85rem;
    font-weight: 600;
    color: #fbbf24;
}

.test-badge {
    margin-left: auto;
    background: rgba(239, 68, 68, 0.3);
    color: #fca5a5;
    padding: 0.15rem 0.5rem;
    border-radius: 4px;
    font-size: 0.7rem;
    font-weight: 700;
    letter-spacing: 0.5px;
}

.test-panel-content {
    padding: 1rem;
}

.test-section {
    margin-bottom: 1rem;
}

.test-section:last-child {
    margin-bottom: 0;
}

.test-section-title {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.test-buttons {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 0.5rem;
}

.test-btn {
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: var(--radius-sm);
    padding: 0.5rem 0.25rem;
    color: var(--text-secondary);
    font-size: 0.7rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-align: center;
}

.test-btn:hover {
    background: rgba(99, 102, 241, 0.2);
    border-color: rgba(99, 102, 241, 0.4);
    color: #a5b4fc;
    transform: translateY(-2px);
}

.test-btn small {
    display: block;
    font-size: 0.6rem;
    color: var(--text-hint);
    margin-top: 2px;
}

.test-import-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.5rem;
}

.test-import-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(34, 197, 94, 0.1);
    border: 1px solid rgba(34, 197, 94, 0.3);
    border-radius: var(--radius-sm);
    padding: 0.5rem;
    color: #86efac;
    font-size: 0.75rem;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.test-import-btn:hover {
    background: rgba(34, 197, 94, 0.2);
    border-color: rgba(34, 197, 94, 0.5);
}

/* Phase Export/Import Buttons in Page Actions */
.action-btn.export {
    background: linear-gradient(135deg, #059669 0%, #047857 100%);
}

.action-btn.export:hover {
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
}

.action-btn.import {
    background: linear-gradient(135deg, #0891b2 0%, #0e7490 100%);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.action-btn.import:hover {
    background: linear-gradient(135deg, #06b6d4 0%, #0891b2 100%);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(6, 182, 212, 0.3);
}