:root {
    /* Base font size */
    --base-font-size: 1rem;
    /* Mobile font size */
    --mobile-font-size: 0.9rem;
}

/* Reset margins and paddings */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: var(--base-font-size);
}

body {
    font-family: 'Poppins', 'Roboto', sans-serif;
    background-color: #f9f9fb;
    color: #333;
    scroll-behavior: smooth;
    line-height: 1.6;
    margin: 0;
    padding: 0;
}

@media (max-width: 767.98px) {
    html {
        font-size: var(--mobile-font-size);
    }
}

.custom-navbar {
    background: linear-gradient(135deg, #007BFF 0%, #6610f2 100%);
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
}

.navbar-brand {
    font-weight: 700;
    font-size: 1.25rem; 
}

.navbar-nav .nav-link {
    color: #fff !important;
    font-weight: 500;
    transition: color 0.3s ease;
}

.navbar-nav .nav-link:hover {
    color: #d9d9d9 !important;
}

.hero-section {
    padding-top: 6rem; 
    padding-bottom: 4rem; 
    background: linear-gradient(135deg, #f1f3f5 0%, #ffffff 100%);
    text-align: center;
}

.hero-title {
    font-size: 2.7rem;
    font-weight: 800; 
    color: #343a40;
    margin-bottom: 1.5rem; 
    line-height: 1.3;
}

.hero-subtitle {
    font-size: 1.2rem; 
    color: #6c757d;
    line-height: 1.6;
    /* Limit width on small screens for readability */
    margin: 0 auto 2rem; 
}

.section {
    padding: 50px 0; 
}

.section-bg-light {
    background: #f1f3f5;
}

.section-title h2 {
    font-size: 2.5rem;
    font-weight: 800; 
    color: #343a40;
    margin-bottom: 1.5rem; 
    line-height: 1.3;
}

.section-title p {
    font-size: 1rem; 
    color: #6c757d;
    line-height: 1.6;
    margin-bottom: 2rem;
}

/* On mobile, limit paragraph and subtitle width for better readability */
@media (max-width: 767.98px) {
    .hero-subtitle,
    .section-title p {
        max-width: 600px;
        margin-left: auto;
        margin-right: auto;
    }
}

/* Converter and Cards */
.converter-container, .feature-card, .step-card, .feature-detail-card {
    background: #ffffff;
    border-radius: 15px;
    box-shadow: 0 5px 20px rgba(0,0,0,0.05);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    padding: 2.5rem;
}

.converter-container:hover,
.feature-card:hover,
.step-card:hover,
.feature-detail-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

/* Feature and Step Titles */
.feature-title, .card-title {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: 1.25rem; 
    color: #343a40;
    line-height: 1.3;
}

.feature-text, .card-text {
    color: #6c757d;
    font-size: 1.05rem; 
    line-height: 1.6;
}

/* Section Background Gradients */
.section-bg-gradient {
    background: linear-gradient(135deg, #f1f3f5 0%, #ffffff 100%);
}

/* Decorative Sections */
.decorative-section {
    position: relative;
    overflow: hidden;
    background: #fff;
}

.decorative-section::before {
    content: "";
    position: absolute;
    top: -50px;
    left: -50px;
    width: 200px;
    height: 200px;
    background: radial-gradient(circle at center, rgba(0,123,255,0.1), transparent 70%);
    z-index: 0;
}

.decorative-section::after {
    content: "";
    position: absolute;
    bottom: -50px;
    right: -50px;
    width: 200px;
    height: 200px;
    background: radial-gradient(circle at center, rgba(102,16,242,0.1), transparent 70%);
    z-index: 0;
}

.decorative-section > .container, 
.section > .container {
    position: relative;
    z-index: 1;
}

/* Hover Raise Effect */
.hover-raise:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

/* Conversion Form Styles */
.conversion-form-container {
    max-width: 800px;
    margin: 0 auto;
}

.dropzone-container {
    border: 2px dashed #6610f2;
    border-radius: 10px;
    padding: 40px;
    text-align: center;
    cursor: pointer;
    transition: background-color 0.3s ease, border-color 0.3s ease;
    background-color: #f9f9fb;
}

.dropzone-container.dragover {
    background-color: #e6e6e6;
    border-color: #007BFF;
}

.dropzone-container p {
    font-size: 1.1rem;
    color: #6c757d;
    margin-bottom: 1rem;
}

#select-files-btn {
    background-color: #6610f2;
    border: none;
    color: #fff;
    padding: 12px 24px;
    font-size: 1rem;
    border-radius: 5px;
    transition: background-color 0.3s ease;
}

#select-files-btn:hover {
    background-color: #520dc2;
}

.file-item {
    background-color: #f1f3f5;
    border: 1px solid #ced4da;
    border-radius: 5px;
    padding: 10px 15px;
    margin-bottom: 5px;
    font-size: 0.95rem;
    color: #495057;
}

.convert-btn {
    background: linear-gradient(135deg, #007BFF 0%, #6610f2 100%);
    border: none;
    color: #fff;
    transition: background 0.3s ease;
}

.convert-btn:hover {
    background: linear-gradient(135deg, #0069d9 0%, #5a2dbf 100%);
}

/* Result Display Styles */
#result .alert {
    font-size: 1rem;
    padding: 15px;
}

#result .btn-success {
    margin-top: 10px;
}

/* Language Selection Buttons */
.language-btn {
    font-size: 1rem;
    padding: 10px 20px;
    border-radius: 5px;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.language-btn:hover {
    background-color: #007BFF;
    color: #fff;
}

/* Responsive Adjustments */
@media (max-width: 767.98px) {
    .dropzone-container {
        padding: 30px;
    }

    #select-files-btn {
        width: 100%;
    }

    .language-btn {
        padding: 8px 16px;
        font-size: 0.9rem;
    }
}


/* Custom styles for multi-column dropdown */
.multi-column-dropdown {
    width: 1000px; /* Установите подходящую ширину для выпадающего меню */
}

.multi-column-dropdown .dropdown-menu {
    padding: 0; /* Удаление стандартных отступов */
}

.multi-column-dropdown .dropdown-item {
    padding: 8px 12px; /* Настройка отступов для элементов */
    white-space: normal; /* Позволяет переносить текст на новую строку */
}

@media (max-width: 991.98px) {
    .multi-column-dropdown {
        width: 100%; /* На меньших экранах меню занимает всю ширину */
    }
}