/* Base styles */
:root {
    --primary-blue: #007bff;
    --primary-hover: #0056b3;
    --text-color: #fff;
    --border-color: rgba(255, 255, 255, 0.2);
    --background: #1a1a2e;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: var(--background);
    color: var(--text-color);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    padding: 20px 0;
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
}

.logo a {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: var(--text-color);
}

.logo-img {
    height: 40px;
    margin-right: 10px;
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 600;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 20px;
}

nav a {
    color: var(--text-color);
    text-decoration: none;
    padding: 8px 16px;
    border-radius: 4px;
    transition: background-color 0.2s;
}

nav a:hover {
    background-color: rgba(255, 255, 255, 0.1);
}

/* Main content */
main {
    flex: 1;
    padding: 40px 0;
}

.page-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 40px;
    font-weight: 600;
}

/* Upload area */
.upload-container {
    max-width: 800px;
    margin: 0 auto;
}

.upload-area {
    border: 2px dashed #fff;
    border-radius: 8px;
    padding: 40px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    background: transparent;
    position: relative;
}

.upload-area:hover {
    border-color: var(--primary-blue);
    background: rgba(0, 123, 255, 0.05);
}

.upload-area.active {
    border-color: var(--primary-blue);
    background: rgba(0, 123, 255, 0.1);
}

.upload-icon {
    font-size: 48px;
    color: var(--primary-blue);
    margin-bottom: 20px;
}

.upload-text {
    font-size: 1.1rem;
    color: var(--text-color);
    margin-bottom: 20px;
}

.browse-text {
    color: var(--primary-blue);
    cursor: pointer;
    text-decoration: none;
}

.browse-text:hover {
    text-decoration: underline;
}

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

.select-button {
    background-color: var(--primary-blue);
    color: #fff;
    border: none;
    border-radius: 4px;
    padding: 12px 24px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s;
}

.select-button:hover {
    background-color: var(--primary-hover);
}

/* Footer */
footer {
    text-align: center;
    padding: 20px 0;
    color: rgba(255, 255, 255, 0.7);
}

/* Responsive */
@media (max-width: 768px) {
    .page-title {
        font-size: 2rem;
    }
    
    .upload-area {
        padding: 30px 20px;
    }
    
    header .container {
        flex-direction: column;
        gap: 20px;
    }
    
    nav ul {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .page-title {
        font-size: 1.8rem;
    }
    
    .upload-text {
        font-size: 1rem;
    }
    
    .select-button {
        padding: 10px 20px;
    }
}