:root {
    /* Default Dark Theme Colors */
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --bg-main: #0f172a;
    --bg-gradient: radial-gradient(circle at 0% 0%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 100% 100%, rgba(168, 85, 247, 0.15) 0%, transparent 50%);
    --card-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --success: #10b981;
    --error: #ef4444;
    --box-bg: rgba(15, 23, 42, 0.3);
}

@media (prefers-color-scheme: light) {
    :root {
        --bg-main: #f1f5f9;
        --bg-gradient: radial-gradient(circle at 0% 0%, rgba(99, 102, 241, 0.08) 0%, transparent 50%),
            radial-gradient(circle at 100% 100%, rgba(168, 85, 247, 0.08) 0%, transparent 50%);
        --card-bg: rgba(255, 255, 255, 0.85);
        --glass-border: rgba(0, 0, 0, 0.05);
        --text-primary: #1e293b;
        --text-secondary: #64748b;
        --box-bg: rgba(241, 255, 255, 0.5);
    }
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-main);
    background-image: var(--bg-gradient);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow-x: hidden;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    width: 100%;
    max-width: 600px;
    padding: 2rem;
    z-index: 10;
}

.card {
    background: var(--card-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 2.5rem;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    animation: fadeIn 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

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

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

header {
    text-align: center;
    margin-bottom: 2.5rem;
}

h1 {
    font-size: 2.25rem;
    font-weight: 700;
    letter-spacing: -0.025em;
    margin-bottom: 0.75rem;
    background: linear-gradient(to right, #818cf8, #c084fc);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* Upload Area */
.upload-zone {
    border: 2px dashed var(--glass-border);
    border-radius: 20px;
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    background: var(--box-bg);
    margin-bottom: 2rem;
    position: relative;
}

.upload-zone:hover,
.upload-zone.dragover {
    border-color: var(--primary);
    background: rgba(99, 102, 241, 0.05);
    transform: scale(1.01);
}

.upload-icon {
    font-size: 3rem;
    margin-bottom: 1.25rem;
    display: block;
    filter: drop-shadow(0 0 10px rgba(99, 102, 241, 0.3));
}

.upload-text {
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.upload-hint {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

#fileInput {
    display: none;
}

/* Task List */
.task-list {
    margin-top: 2rem;
}

.task-item {
    background: var(--box-bg);
    border-radius: 16px;
    padding: 1rem;
    margin-bottom: 1rem;
    border: 1px solid var(--glass-border);
    display: flex;
    align-items: center;
    gap: 1.25rem;
    animation: slideIn 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.task-thumb {
    width: 60px;
    height: 60px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.05);
    flex-shrink: 0;
    object-fit: cover;
    border: 1px solid var(--glass-border);
}

.task-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    min-width: 0;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-10px);
    }

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

.task-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
}

.task-name {
    font-size: 0.95rem;
    font-weight: 500;
    word-break: break-all;
    flex: 1;
    margin-right: 1rem;
}

.task-status {
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    text-transform: uppercase;
    letter-spacing: 0.025em;
    flex-shrink: 0;
}

.status-pending {
    background: rgba(234, 179, 8, 0.1);
    color: #eab308;
}

.status-processing {
    background: rgba(99, 102, 241, 0.1);
    color: #818cf8;
}

.status-completed {
    background: rgba(16, 185, 129, 0.1);
    color: #10b981;
}

.status-failed {
    background: rgba(239, 68, 68, 0.1);
    color: #ef4444;
}

/* Progress Bar */
.progress-container {
    height: 6px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 10px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background: var(--primary);
    width: 0%;
    transition: width 0.4s ease;
    box-shadow: 0 0 10px rgba(99, 102, 241, 0.5);
}

.task-result {
    display: flex;
    justify-content: flex-end;
}

.download-btn {
    background: var(--primary);
    color: white;
    text-decoration: none;
    padding: 0.5rem 1.25rem;
    border-radius: 12px;
    font-size: 0.875rem;
    font-weight: 600;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.delete-btn {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--glass-border);
    padding: 0.5rem 0.75rem;
    border-radius: 12px;
    font-size: 0.8125rem;
    cursor: pointer;
    transition: all 0.2s;
    margin-left: 0.5rem;
}

.delete-btn:hover {
    background: rgba(239, 68, 68, 0.1);
    color: var(--error);
    border-color: var(--error);
}

/* Responsive */
@media (max-width: 640px) {
    .container {
        padding: 1rem;
    }

    .card {
        padding: 1.5rem;
    }

    h1 {
        font-size: 1.75rem;
    }
}