:root {
    /* Color Scheme - Easy to change */
    --primary-color: #e53e3e;
    --primary-dark: #c53030;
    --primary-light: #fed7d7;
    --primary-lighter: #fef5f5;
    --primary-lightest: #fff5f5;
    
    /* Text Colors */
    --text-primary: #2d3748;
    --text-secondary: #718096;
    --text-muted: #a0aec0;
    --text-white: #ffffff;
    
    /* Background Colors */
    --bg-white: #ffffff;
    --bg-light: #f7fafc;
    --bg-lighter: #fafafa;
    --bg-gray: #edf2f7;
    
    /* Border Colors */
    --border-light: #e2e8f0;
    --border-gray: #cbd5e0;
    
    /* Success Colors */
    --success-bg: #f0fff4;
    --success-text: #22543d;
    --success-border: #9ae6b4;
    
    /* Error Colors */
    --error-bg: var(--primary-light);
    --error-text: #742a2a;
    --error-border: #feb2b2;
    
    /* Spacing */
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-md: 16px;
    --spacing-lg: 20px;
    --spacing-xl: 24px;
    --spacing-2xl: 32px;
    
    /* Border Radius */
    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 25px;
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 8px rgba(0,0,0,0.1);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.1);
    --shadow-primary: 0 4px 12px rgba(229, 62, 62, 0.3);
    --shadow-primary-lg: 0 6px 20px rgba(229, 62, 62, 0.4);
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, var(--primary-lightest) 0%, var(--primary-light) 100%);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
}

.container {
    max-width: 100%;
    margin: 0 auto;
    background: var(--bg-white);
    min-height: 100vh;
    box-shadow: var(--shadow-lg);
}

.tab-container {
    background: var(--bg-white);
    display: flex;
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 99;
}

.tab {
    flex: 1;
    padding: var(--spacing-md) var(--spacing-md);
    text-align: center;
    background: var(--bg-light);
    border: none;
    cursor: pointer;
    font-size: 16px;
    font-weight: 700;
    color: var(--text-secondary);
    border-bottom: 3px solid transparent;
    transition: all var(--transition-normal);
    position: relative;
    font-family: 'Inter', sans-serif;
    letter-spacing: -0.3px;
    text-transform: uppercase;
}

.tab:hover {
    background: var(--bg-gray);
    color: var(--text-primary);
}

.tab.active {
    background: var(--bg-white);
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

.tab.active::after {
    content: '';
    position: absolute;
    bottom: -3px;
    left: 50%;
    transform: translateX(-50%);
    width: 40px;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color), var(--primary-dark));
    border-radius: 2px;
}

.content {
    background: var(--bg-white);
    min-height: calc(100vh - 72px);
    padding: var(--spacing-xl) var(--spacing-lg);
}

.message {
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
    font-weight: 500;
    animation: slideInDown 0.5s ease-out;
    position: relative;
}

.message.success {
    background: var(--success-bg);
    color: var(--success-text);
    border: 1px solid var(--success-border);
    box-shadow: 0 4px 12px rgba(34, 84, 61, 0.1);
}

.message.error {
    background: var(--error-bg);
    color: var(--error-text);
    border: 1px solid var(--error-border);
    box-shadow: 0 4px 12px rgba(116, 42, 42, 0.1);
}

@keyframes slideInDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Form reset animation */
.form-reset {
    animation: formReset 0.3s ease-out;
}

@keyframes formReset {
    0% { opacity: 1; }
    50% { opacity: 0.7; }
    100% { opacity: 1; }
}

.user-info {
    padding: 0;
    margin-bottom: var(--spacing-xl);
    font-size: 14px;
    color: var(--text-secondary);
    font-weight: 400;
}

.section-title {
    font-size: 18px;
    font-weight: 800;
    margin-bottom: var(--spacing-xs);
    color: var(--text-primary);
    letter-spacing: -0.4px;
    font-family: 'Inter', sans-serif;
}

.section-subtitle {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
    line-height: 1.5;
}

.suggestion-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xl);
}

.suggestion-btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    border: 2px solid var(--border-light);
    background: var(--bg-white);
    border-radius: var(--radius-full);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
    color: var(--text-primary);
    box-shadow: var(--shadow-sm);
}

.suggestion-btn:hover {
    border-color: var(--primary-light);
    background: var(--primary-lightest);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.suggestion-btn.selected {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: var(--text-white);
    border-color: var(--primary-color);
    box-shadow: var(--shadow-primary);
}

.form-group {
    margin-bottom: var(--spacing-xl);
}

.textarea {
    width: 100%;
    min-height: 120px;
    padding: var(--spacing-md);
    border: 2px solid var(--border-light);
    border-radius: var(--spacing-sm);
    font-size: 15px;
    resize: vertical;
    font-family: inherit;
    transition: all var(--transition-normal);
    background: var(--bg-lighter);
}

.textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    background: var(--bg-white);
    box-shadow: 0 0 0 3px rgba(229, 62, 62, 0.1);
}

.char-counter {
    text-align: right;
    font-size: 12px;
    color: var(--text-muted);
    margin-top: var(--spacing-xs);
    font-weight: 500;
}

.upload-section {
    margin-bottom: var(--spacing-xl);
}

.upload-container {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.upload-previews {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    align-items: flex-start;
}

.upload-btn {
    width: 80px;
    height: 80px;
    border: 3px dashed var(--border-light);
    background: var(--bg-lighter);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 32px;
    color: var(--primary-color);
    transition: all var(--transition-normal);
    flex-shrink: 0;
}

.upload-btn:hover {
    border-color: var(--primary-color);
    background: var(--primary-lightest);
    transform: scale(1.05);
    box-shadow: var(--shadow-primary);
}

.upload-preview {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
    width: 120px;
}

.preview-image {
    width: 120px;
    height: 80px;
    object-fit: cover;
    border-radius: var(--radius-lg);
    border: 2px solid var(--border-light);
    box-shadow: var(--shadow-md);
}

.preview-info {
    font-size: 12px;
    color: var(--text-secondary);
}

.preview-name {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 2px;
    word-break: break-all;
    font-size: 11px;
}

.remove-image {
    background: var(--primary-color);
    color: var(--text-white);
    border: none;
    padding: 4px var(--spacing-xs);
    border-radius: var(--radius-sm);
    font-size: 11px;
    cursor: pointer;
    transition: all var(--transition-fast);
    margin-top: 4px;
    width: 100%;
}

.remove-image:hover {
    background: var(--primary-dark);
}

.upload-info {
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: var(--spacing-sm);
}

#upload-counter {
    font-weight: 600;
    color: var(--primary-color);
}

.contact-section {
    margin-bottom: var(--spacing-2xl);
}

.input-field {
    width: 100%;
    padding: var(--spacing-md) 0;
    border: none;
    border-bottom: 2px solid var(--border-light);
    font-size: 15px;
    background: transparent;
    margin-bottom: var(--spacing-lg);
    transition: all var(--transition-normal);
    color: var(--text-primary);
}

.input-field:focus {
    outline: none;
    border-bottom-color: var(--primary-color);
    box-shadow: 0 2px 0 rgba(229, 62, 62, 0.2);
}

.input-field::placeholder {
    color: var(--text-muted);
    font-weight: 400;
}

.submit-btn {
    width: 100%;
    padding: 18px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: var(--text-white);
    border: none;
    border-radius: var(--radius-lg);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    margin-bottom: var(--spacing-xl);
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-primary);
    letter-spacing: 0.5px;
}

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

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

.footer-text {
    text-align: center;
    font-size: 13px;
    color: var(--text-secondary);
    line-height: 1.6;
    padding: 0;
    margin-top: var(--spacing-md);
}

.tab-content {
    display: none;
    animation: fadeIn var(--transition-normal) ease-in-out;
}

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

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

#file-input {
    display: none;
}

/* Mobile Optimizations */
@media (max-width: 768px) {
    .container {
        box-shadow: none;
    }
    
    .tab {
        padding: var(--spacing-md) var(--spacing-sm);
        font-size: 15px;
    }
    
    .content {
        padding: var(--spacing-lg) var(--spacing-md);
        min-height: calc(100vh - 60px);
    }
    
    .suggestion-buttons {
        gap: var(--spacing-xs);
    }
    
    .suggestion-btn {
        padding: 10px var(--spacing-md);
        font-size: 13px;
    }
    
    .upload-container {
        flex-direction: row;
        align-items: flex-start;
        justify-content: flex-start;
    }

    .upload-previews {
        flex-direction: row;
        flex-wrap: wrap;
    }

    .upload-preview {
        width: 100px;
    }

    .preview-image {
        width: 100px;
        height: 67px;
    }

    .preview-info {
        max-width: 100px;
    }
    
    .upload-btn {
        width: 70px;
        height: 70px;
        font-size: 28px;
    }
}

/* Touch-friendly improvements */
@media (hover: none) and (pointer: coarse) {
    .suggestion-btn, .submit-btn, .upload-btn {
        min-height: 44px;
    }
    
    .tab {
        min-height: 48px;
    }
}