/* ===== app/static/css/main.css ===== */
/* 主要样式文件 - 整合增强版 */

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* 原有 Color Palette */
    --primary-50: #eff6ff;
    --primary-100: #dbeafe;
    --primary-500: #3b82f6;
    --primary-600: #2563eb;
    --primary-700: #1d4ed8;
    --primary-900: #1e3a8a;
    
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    --green-50: #ecfdf5;
    --green-500: #10b981;
    --green-600: #059669;
    
    --orange-500: #f59e0b;
    --orange-600: #d97706;
    
    --purple-50: #faf5ff;
    --purple-500: #8b5cf6;
    --purple-600: #7c3aed;
    
    --red-500: #ef4444;
    --red-600: #dc2626;
    
    /* Pillar 2 特定颜色 */
    --pillar2-primary: #667eea;
    --pillar2-secondary: #764ba2;
    --pillar2-accent: #f093fb;
    --pillar2-success: #53f3c0;
    
    /* 流程步骤颜色 */
    --step-etr: #3498db;
    --step-qdmtt: #2ecc71;
    --step-iir: #f39c12;
    --step-utpr: #e74c3c;
    
    /* Typography */
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'SF Mono', Consolas, 'Liberation Mono', Menlo, monospace;
    
    /* Spacing */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.25rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-10: 2.5rem;
    --space-12: 3rem;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --shadow-glow: 0 0 20px rgba(102, 126, 234, 0.3);
    --shadow-heavy: 0 20px 40px rgba(0, 0, 0, 0.15);
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.2s ease;
    --transition-slow: 0.3s ease;
    --transition-bounce: 0.3s cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

body {
    font-family: var(--font-sans);
    background: linear-gradient(135deg, var(--pillar2-primary) 0%, var(--pillar2-secondary) 100%);
    color: var(--gray-900);
    line-height: 1.6;
    min-height: 100vh;
}

/* ===== Header Components ===== */
.app-header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    color: var(--gray-900);
    margin: var(--space-5);
    padding: var(--space-8);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    position: relative;
    overflow: hidden;
}

.app-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--pillar2-primary), var(--pillar2-secondary), var(--pillar2-accent));
    animation: shimmer 3s ease-in-out infinite;
}

.header-content {
    max-width: 1400px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    gap: var(--space-4);
    min-height: 60px;
}

.app-logo {
    grid-column: 2;
    display: flex;
    align-items: center;
    gap: var(--space-4);
    justify-self: center;
}

.app-logo i {
    font-size: 2.5rem;
    background: linear-gradient(135deg, var(--pillar2-primary), var(--pillar2-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.app-logo h1 {
    font-size: 1.75rem;
    font-weight: 700;
    margin: 0;
    background: linear-gradient(135deg, var(--pillar2-primary), var(--pillar2-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-align: center;
}

.app-logo .subtitle {
    font-size: 0.875rem;
    color: var(--gray-600);
    margin-top: var(--space-1);
    text-align: center;
}

.header-controls {
    grid-column: 3;
    display: flex;
    align-items: center;
    gap: var(--space-6);
    flex-wrap: wrap;
    justify-self: end;
}

.model-selector {
    padding: var(--space-3) var(--space-5);
    border: 2px solid var(--gray-300);
    border-radius: 25px;
    background: white;
    font-weight: 500;
    color: var(--gray-700);
    cursor: pointer;
    transition: all var(--transition-normal);
    min-width: 200px;
}

.model-selector:hover {
    border-color: var(--pillar2-primary);
    box-shadow: var(--shadow-md);
}

.model-selector:focus {
    outline: none;
    border-color: var(--pillar2-primary);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.2);
}

.language-toggle {
    display: flex;
    background: var(--gray-100);
    border-radius: 25px;
    overflow: hidden;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.1);
}

.lang-option {
    padding: var(--space-2) var(--space-5);
    border: none;
    background: transparent;
    cursor: pointer;
    font-weight: 500;
    color: var(--gray-600);
    transition: all var(--transition-normal);
    position: relative;
}

.lang-option:hover {
    color: var(--gray-900);
}

.lang-option.active {
    background: linear-gradient(135deg, var(--pillar2-primary), var(--pillar2-secondary));
    color: white;
    box-shadow: var(--shadow-sm);
}

/* ===== Main Layout ===== */
.app-main {
    max-width: none;
    margin: 0 auto;
    padding: 0 var(--space-4) var(--space-4) var(--space-4);
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: var(--space-5);
    min-height: calc(100vh - 160px);
}

/* ===== Sidebar ===== */
.app-sidebar {
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    border-radius: var(--radius-xl);
    padding: var(--space-6) 0;
    box-shadow: var(--shadow-lg);
    height: fit-content;
    position: sticky;
    top: var(--space-5);
}

.sidebar-header {
    padding: 0 var(--space-8) var(--space-5) var(--space-8);
    border-bottom: 1px solid var(--gray-200);
    margin-bottom: var(--space-5);
}

.sidebar-header h3 {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--gray-900);
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    padding: var(--space-4) var(--space-8);
    border: none;
    background: transparent;
    color: var(--gray-600);
    cursor: pointer;
    transition: all var(--transition-normal);
    text-align: left;
    font-size: 0.95rem;
    font-weight: 500;
    position: relative;
}

.nav-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 0;
    background: linear-gradient(135deg, var(--pillar2-primary), var(--pillar2-secondary));
    transition: width var(--transition-normal);
}

.nav-item:hover {
    color: var(--gray-900);
    background: rgba(102, 126, 234, 0.05);
}

.nav-item:hover::before {
    width: 4px;
}

.nav-item.active {
    color: var(--pillar2-primary);
    background: rgba(102, 126, 234, 0.1);
    font-weight: 600;
}

.nav-item.active::before {
    width: 4px;
}

.nav-item i {
    font-size: 1.1rem;
    width: 20px;
    text-align: center;
}

/* ===== Main Content ===== */
.app-content {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    box-shadow: var(--shadow-lg);
    position: relative;
    width: 100%;
    max-width: none;
}

.content-section {
    display: none;
    animation: fadeInUp 0.6s ease;
}

.content-section.active {
    display: block;
}

.content-header {
    text-align: center;
    margin-bottom: var(--space-10);
    position: relative;
}

.content-title {
    font-size: 2.2rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: var(--space-4);
    position: relative;
}

.content-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 3px;
    background: linear-gradient(90deg, var(--pillar2-primary), var(--pillar2-secondary));
    border-radius: 2px;
}

.content-subtitle {
    font-size: 1.1rem;
    color: var(--gray-600);
    line-height: 1.6;
    max-width: 600px;
    margin: 0 auto;
}

.content-body {
    margin-bottom: var(--space-10);
}

/* ===== Workflow Section ===== */
.workflow-section {
    margin-bottom: var(--space-12);
    background: white;
    padding: var(--space-8);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    width: 100%;
}

.section-header {
    text-align: center;
    margin-bottom: var(--space-8);
}

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: var(--space-3);
    display: flex;
    align-items: center;
    justify-content: center;
}

.section-subtitle {
    font-size: 1rem;
    color: var(--gray-600);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.6;
}

.workflow-container {
    position: relative;
    max-width: none;
    margin: 0 auto;
    padding: var(--space-5);
    width: 100%;
}

.workflow-steps {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-6);
    margin-bottom: var(--space-8);
    width: 100%;
}

.workflow-step {
    background: white;
    border-radius: var(--radius-xl);
    padding: var(--space-5);
    text-align: center;
    position: relative;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
    cursor: pointer;
    border-top: 4px solid var(--step-color);
    min-height: 280px;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
}

.workflow-step:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-heavy);
}

.workflow-step.step-active {
    transform: translateY(-5px);
    box-shadow: var(--shadow-heavy);
    border-top-width: 6px;
}

.workflow-step.step-active .step-icon {
    transform: scale(1.1);
}

.step-icon {
    width: 70px;
    height: 70px;
    margin: 0 auto var(--space-4);
    background: var(--step-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    color: white;
    position: relative;
    overflow: hidden;
}

.step-icon::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(45deg, transparent 30%, rgba(255,255,255,0.3) 50%, transparent 70%);
    transform: translateX(-100%);
    animation: shine 2s ease-in-out infinite;
}

.step-number {
    position: absolute;
    top: -10px;
    right: -10px;
    width: 28px;
    height: 28px;
    background: var(--red-500);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 0.9rem;
    box-shadow: var(--shadow-md);
}

.step-title {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--gray-900);
    margin-bottom: var(--space-3);
}

.step-description {
    color: var(--gray-600);
    line-height: 1.6;
    margin-bottom: var(--space-4);
}

.step-details {
    display: none;
    margin-top: auto;
    padding-top: var(--space-5);
    border-top: 1px solid var(--gray-200);
    text-align: left;
    flex-grow: 1;
}

.step-details.show {
    display: block;
    animation: fadeIn 0.3s ease;
}

.step-formula {
    background: var(--gray-50);
    padding: var(--space-3);
    border-radius: var(--radius-md);
    font-size: 0.9rem;
    color: var(--gray-700);
    border-left: 4px solid var(--step-color);
    text-align: left;
    line-height: 1.5;
    margin-bottom: var(--space-3);
}

/* Step color themes */
.step-etr { --step-color: var(--step-etr); }
.step-qdmtt { --step-color: var(--step-qdmtt); }
.step-iir { --step-color: var(--step-iir); }
.step-utpr { --step-color: var(--step-utpr); }

/* ===== Stats Section ===== */
.stats-section {
    background: linear-gradient(135deg, var(--pillar2-primary), var(--pillar2-secondary));
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    margin: var(--space-6) 0;
    color: white;
    text-align: center;
}

.stats-title {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: var(--space-4);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-4);
    max-width: none;
}

.stat-item {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: bold;
    color: white;
    margin-bottom: var(--space-1);
}

.stat-label {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.9);
}

/* ===== Decision Flow ===== */
.decision-flow {
    margin-top: var(--space-8);
    padding: var(--space-6);
    background: var(--gray-50);
    border-radius: var(--radius-lg);
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
}

.flow-chart {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-3);
    max-width: 400px;
    margin: 0 auto;
}

.flow-node {
    background: white;
    border-radius: var(--radius-lg);
    padding: var(--space-4);
    box-shadow: var(--shadow-sm);
    min-width: 200px;
    text-align: center;
    border: 2px solid var(--gray-200);
    font-weight: 500;
}

.flow-node.decision {
    background: #fff3cd;
    border-color: #ffeaa7;
    border-radius: 25px;
}

.flow-node.action {
    background: #d1ecf1;
    border-color: #7dd3fc;
}

.flow-arrow {
    font-size: 1.2rem;
    color: var(--pillar2-primary);
    font-weight: bold;
    margin: var(--space-1) 0;
}

/* ===== Introduction Sections ===== */
.intro-section {
    margin-bottom: var(--space-8);
    background: white;
    padding: var(--space-8);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    border-left: 4px solid var(--pillar2-primary);
}

.intro-title {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--gray-900);
    margin-bottom: var(--space-4);
}

.intro-text {
    color: var(--gray-700);
    line-height: 1.7;
    margin-bottom: var(--space-4);
}

.intro-features {
    list-style: none;
    margin-bottom: var(--space-4);
}

.intro-features li {
    display: flex;
    align-items: flex-start;
    gap: var(--space-3);
    margin-bottom: var(--space-3);
    color: var(--gray-700);
    line-height: 1.6;
}

.intro-features i {
    color: var(--green-500);
    margin-top: 2px;
    flex-shrink: 0;
}

.intro-steps {
    counter-reset: step-counter;
    list-style: none;
    margin-bottom: var(--space-4);
}

.intro-steps li {
    counter-increment: step-counter;
    position: relative;
    padding-left: var(--space-10);
    margin-bottom: var(--space-4);
    color: var(--gray-700);
    line-height: 1.6;
}

.intro-steps li::before {
    content: counter(step-counter);
    position: absolute;
    left: 0;
    top: 0;
    width: 24px;
    height: 24px;
    background: var(--pillar2-primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 0.875rem;
}

.paper-section {
    background: linear-gradient(135deg, var(--purple-50), var(--primary-50));
    border-left-color: var(--purple-500);
}

.paper-link {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    color: var(--purple-600);
    text-decoration: none;
    font-weight: 600;
    padding: var(--space-3) var(--space-6);
    border: 2px solid var(--purple-600);
    border-radius: var(--radius-lg);
    transition: all var(--transition-normal);
}

.paper-link:hover {
    background: var(--purple-600);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* ===== Action Buttons ===== */
.action-bar {
    display: flex;
    justify-content: center;
    gap: var(--space-4);
    flex-wrap: wrap;
    padding-top: var(--space-8);
    border-top: 1px solid var(--gray-200);
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    border: 2px solid transparent;
    border-radius: 25px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    text-decoration: none;
    position: relative;
    overflow: hidden;
}

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

.btn-primary {
    background: linear-gradient(135deg, var(--pillar2-primary), var(--pillar2-secondary));
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.btn-secondary {
    background: linear-gradient(135deg, var(--orange-500), var(--orange-600));
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-secondary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.btn-outline {
    background: white;
    color: var(--pillar2-primary);
    border-color: var(--pillar2-primary);
}

.btn-outline:hover {
    background: var(--pillar2-primary);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* ===== Model Selection ===== */
.model-selection {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-6);
    margin-bottom: var(--space-8);
}

.model-card {
    background: white;
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    border: 2px solid var(--gray-200);
    transition: all var(--transition-normal);
    cursor: pointer;
    position: relative;
}

.model-card:hover {
    border-color: var(--pillar2-primary);
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.model-card.selected {
    border-color: var(--pillar2-primary);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1), rgba(118, 75, 162, 0.1));
    box-shadow: var(--shadow-lg);
}

.model-badge {
    position: absolute;
    top: var(--space-4);
    right: var(--space-4);
    background: var(--green-500);
    color: white;
    padding: var(--space-1) var(--space-3);
    border-radius: var(--radius-md);
    font-size: 0.8rem;
    font-weight: 600;
}

.model-badge.enhanced {
    background: var(--orange-500);
}

.model-badge.experimental {
    background: var(--red-500);
}

.model-name {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: var(--space-2);
}

.model-version {
    font-size: 0.9rem;
    color: var(--gray-500);
    margin-bottom: var(--space-4);
}

.model-description {
    color: var(--gray-700);
    line-height: 1.6;
    margin-bottom: var(--space-5);
}

.model-features {
    list-style: none;
}

.model-features li {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    margin-bottom: var(--space-2);
    color: var(--gray-700);
    font-size: 0.9rem;
}

.model-features i {
    color: var(--green-500);
}

/* ===== Form Components ===== */
.config-panel {
    background: white;
    border-radius: var(--radius-xl);
    padding: var(--space-6);
    box-shadow: var(--shadow-md);
    border-left: 4px solid var(--pillar2-primary);
    margin-bottom: var(--space-6);
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-4);
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.form-label {
    font-weight: 600;
    color: var(--gray-700);
    font-size: 0.9rem;
}

.form-input {
    padding: var(--space-3);
    border: 2px solid var(--gray-300);
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    transition: all var(--transition-normal);
}

.form-input:focus {
    outline: none;
    border-color: var(--pillar2-primary);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.2);
}

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

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

@keyframes shine {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

@keyframes shimmer {
    0%, 100% { transform: translateX(-100%); }
    50% { transform: translateX(100%); }
}

/* ===== Loading Animation ===== */
.loading-spinner {
    border: 4px solid #f3f3f3;
    border-top: 4px solid var(--pillar2-primary);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 2s linear infinite;
    margin: 0 auto var(--space-4);
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* ===== Scroll Animation Support ===== */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.animate-on-scroll.animate {
    opacity: 1;
    transform: translateY(0);
}

/* ===== Responsive Design ===== */
@media (max-width: 1400px) {
    .workflow-steps {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 1024px) {
    .app-main {
        grid-template-columns: 1fr;
        gap: var(--space-5);
    }
    
    .app-sidebar {
        position: static;
        padding: var(--space-4) 0;
    }

    .sidebar-header {
        padding: 0 var(--space-6) var(--space-4) var(--space-6);
        border-bottom: 1px solid var(--gray-200);
        margin-bottom: var(--space-4);
    }
    
    .sidebar-nav {
        flex-direction: column;
        overflow-x: visible;
        overflow-y: auto;
        padding: 0 var(--space-5);
        max-height: 60vh;
    }
    
    .nav-item {
        white-space: normal;
        min-width: auto;
        width: 100%;
        justify-content: flex-start;
        padding: var(--space-3) var(--space-6);
        font-size: 0.9rem;
    }

    .nav-item i {
        font-size: 1rem;
        width: 18px;
    }
    
    .workflow-steps {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .app-header {
        margin: var(--space-3);
        padding: var(--space-5);
    }
    
    .header-content {
        grid-template-columns: 1fr;
        grid-template-rows: auto auto;
        text-align: center;
        gap: var(--space-6);
    }
    
    .app-logo {
        grid-column: 1;
        grid-row: 1;
        justify-self: center;
    }
    
    .app-logo h1 {
        font-size: 1.5rem;
    }
    
    .header-controls {
        grid-column: 1;
        grid-row: 2;
        justify-self: center;
        flex-direction: column;
        gap: var(--space-4);
    }
    
    .app-main {
        padding: 0 var(--space-3) var(--space-3) var(--space-3);
    }

    .app-sidebar {
        border-radius: var(--radius-lg);
        margin-bottom: var(--space-4);
        padding: var(--space-3) 0;
    }

    .sidebar-header {
        padding: 0 var(--space-4) var(--space-3) var(--space-4);
        margin-bottom: var(--space-3);
    }

    .sidebar-header h3 {
        font-size: 1.1rem;
    }

    .sidebar-nav {
        max-height: 50vh;
    }

    .nav-item {
        padding: var(--space-2) var(--space-4);
        font-size: 0.85rem;
        gap: var(--space-3);
    }

    .nav-item i {
        font-size: 0.9rem;
        width: 16px;
    }
    
    .app-content {
        padding: var(--space-4);
    }
    
    .content-title {
        font-size: 1.8rem;
    }
    
    .workflow-steps {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .action-bar {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .flow-node {
        min-width: 180px;
        font-size: 0.9rem;
    }
    
    .workflow-section {
        padding: var(--space-4);
    }
}

@media (max-width: 480px) {
    .app-logo {
        flex-direction: column;
        gap: var(--space-2);
    }
    
    .app-logo h1 {
        font-size: 1.5rem;
    }
    
    .content-title {
        font-size: 1.6rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .sidebar-nav {
        max-height: 40vh;
    }
    
    .nav-item {
        padding: var(--space-2) var(--space-3);
        font-size: 0.8rem;
        gap: var(--space-2);
    }
    
    .nav-item i {
        font-size: 0.85rem;
        width: 14px;
    }
}

/* ===== Accessibility ===== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

@media (prefers-contrast: high) {
    :root {
        --gray-600: #000000;
        --gray-700: #000000;
        --gray-900: #000000;
    }
}