/* assets/style.css */
:root {
    --primary: #043e7b; /* 3CX Blue-ish tone */
    --primary-hover: #032b57;
    --secondary: #ff5722; /* Certified IT accent */
    --bg-color: #f4f7fb;
    --text-main: #333;
    --text-light: #666;
    --card-bg: #ffffff;
    --border-radius: 12px;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

.container {
    background-color: var(--card-bg);
    max-width: 850px;
    width: 100%;
    border-radius: var(--border-radius);
    box-shadow: 0 10px 30px rgba(0,0,0,0.08);
    padding: 40px;
    text-align: center;
}

header h1 {
    color: var(--primary);
    font-weight: 800;
    font-size: 2.2rem;
    margin-bottom: 10px;
}

header p {
    color: var(--text-light);
    font-size: 1.1rem;
    margin-bottom: 30px;
    line-height: 1.5;
}

/* Form Styles */
.upload-form {
    margin-bottom: 40px;
}

.file-drop-area {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    max-width: 100%;
    padding: 40px;
    border: 2px dashed #c0ccda;
    border-radius: var(--border-radius);
    background-color: #f8fafc;
    transition: 0.3s;
    cursor: pointer;
    margin-bottom: 20px;
}

.file-drop-area:hover, .file-drop-area.is-active {
    background-color: #e2e8f0;
    border-color: var(--primary);
}

.file-msg {
    font-size: 1rem;
    color: var(--text-light);
    pointer-events: none;
}

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

.btn-convert {
    background-color: var(--primary);
    color: white;
    border: none;
    padding: 15px 30px;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: var(--border-radius);
    cursor: pointer;
    width: 100%;
    transition: background-color 0.3s, transform 0.1s;
}

.btn-convert:hover {
    background-color: var(--primary-hover);
    transform: translateY(-2px);
}

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

/* Promo Section */
.promo-section {
    background: linear-gradient(135deg, #043e7b, #135da4);
    color: white;
    padding: 30px;
    border-radius: var(--border-radius);
    margin-bottom: 30px;
    box-shadow: 0 4px 15px rgba(4, 62, 123, 0.3);
}

.badge {
    display: inline-block;
    background-color: var(--secondary);
    color: white;
    padding: 5px 10px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 15px;
}

.promo-section h2 {
    font-size: 1.4rem;
    margin-bottom: 10px;
}

.promo-section p {
    font-size: 0.95rem;
    opacity: 0.9;
    margin-bottom: 20px;
    line-height: 1.5;
}

.btn-promo {
    display: inline-block;
    background-color: white;
    color: var(--primary);
    text-decoration: none;
    padding: 12px 25px;
    border-radius: 30px;
    font-weight: 600;
    transition: transform 0.3s;
}

.btn-promo:hover {
    transform: scale(1.05);
}

/* Footer */
footer {
    border-top: 1px solid #eaeaea;
    padding-top: 20px;
}

.footer-links {
    margin-bottom: 10px;
}

.footer-links a {
    color: var(--primary);
    text-decoration: none;
    font-weight: 600;
    margin: 0 10px;
}

.footer-links a:hover {
    text-decoration: underline;
}

footer p {
    font-size: 0.85rem;
    color: var(--text-light);
}

/* Features Section */
.features-section {
    margin-top: 40px;
    margin-bottom: 40px;
    text-align: left;
}

.features-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
}

.feature-card {
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    border-radius: var(--border-radius);
    padding: 25px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.02);
}

.feature-card h3 {
    color: var(--primary);
    font-size: 1.25rem;
    margin-bottom: 20px;
    border-bottom: 2px solid var(--secondary);
    padding-bottom: 10px;
    display: inline-block;
}

.feature-list {
    list-style: none;
    padding: 0;
}

.feature-list li {
    font-size: 0.95rem;
    margin-bottom: 15px;
    line-height: 1.5;
    position: relative;
    padding-left: 25px;
    color: var(--text-main);
}

.feature-list li strong {
    color: var(--primary);
}

.feature-list li::before {
    content: "✓";
    color: var(--secondary);
    position: absolute;
    left: 0;
    top: 0;
    font-weight: 800;
}

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

@media (max-width: 480px) {
    .container {
        padding: 20px;
    }
    
    header h1 {
        font-size: 1.8rem;
    }
}