@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;900&display=swap');

:root {
    /* Arsum-inspired Palette */
    --primary-start: #0ea5e9;
    --primary-end: #06b6d4;
    --primary-gradient: linear-gradient(135deg, var(--primary-start), var(--primary-end));

    --bg: #f9fafb;
    --surface: #ffffff;
    --text: #1f2937;
    --text-muted: #6b7280;
    --border: #f3f4f6;

    --success: #10b981;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg);
    color: var(--text);
    margin: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background-image: radial-gradient(circle at top right, #e0f2fe 0%, transparent 40%),
        radial-gradient(circle at bottom left, #f3f4f6 0%, transparent 40%);
}

.container {
    width: 100%;
    max-width: 640px;
    padding: 3rem;
    background: var(--surface);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-lg);
    text-align: center;
    margin: 1rem;
}

header {
    margin-bottom: 3rem;
}

header h1 {
    font-size: 3rem;
    font-weight: 900;
    color: var(--text);
    margin: 0 0 0.5rem 0;
    letter-spacing: -0.04em;
    line-height: 1.1;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    display: inline-block;
}

header p {
    color: var(--text-muted);
    font-size: 1.125rem;
    margin: 0.5rem 0 0 0;
    font-weight: 400;
}

.drop-zone {
    border: 3px dashed #e2e8f0;
    border-radius: var(--radius-lg);
    padding: 4rem 2rem;
    background: #f8fafc;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    position: relative;
    overflow: hidden;
}

.drop-zone:hover,
.drop-zone.drag-over {
    border-color: #38bdf8;
    background: #f0f9ff;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.drop-zone svg {
    margin-bottom: 1.5rem;
    color: #94a3b8;
    transition: color 0.3s ease;
    width: 64px;
    height: 64px;
}

.drop-zone:hover svg {
    color: #0ea5e9;
}

.drop-message p {
    font-weight: 500;
    font-size: 1.1rem;
}

.file-list {
    margin-top: 2.5rem;
    text-align: left;
}

.file-item {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.25rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: var(--shadow-sm);
    animation: slideIn 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.file-info {
    flex: 1;
}

.filename {
    font-weight: 600;
    display: block;
    margin-bottom: 0.25rem;
    color: var(--text);
}

.status {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.status.success {
    color: var(--success);
    font-weight: 600;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    padding: 0.75rem 1.5rem;
    background: var(--primary-gradient);
    color: white;
    text-decoration: none;
    border-radius: 9999px;
    /* Pill shape */
    font-size: 0.95rem;
    font-weight: 600;
    transition: all 0.2s ease;
    margin-left: 1rem;
    box-shadow: 0 4px 6px -1px rgba(14, 165, 233, 0.3);
}

.download-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 6px 8px -1px rgba(14, 165, 233, 0.4);
    filter: brightness(1.1);
}

.progress-bar-container {
    width: 100%;
    height: 6px;
    background: #e2e8f0;
    border-radius: 9999px;
    margin-top: 0.75rem;
    overflow: hidden;
    display: none;
}

.progress-bar {
    height: 100%;
    background: var(--primary-gradient);
    width: 0%;
    transition: width 0.3s ease-out;
    border-radius: 9999px;
}

.loading .progress-bar-container {
    display: block;
}