:root {
    --primary-color: #007aff;
    --primary-hover: #0062cc;
    --accent-color: #5ac8fa;
    --bg-color: #f0f2f5;
    --card-bg: #ffffff;
    --text-primary: #1c1e21;
    --text-secondary: #606770;
    --border-color: #e4e6eb;
    --success-color: #34c759;
    --error-color: #ff3b30;
    --warn-color: #ffcc00;
    --log-bg: #f7f9fc;
    --log-text: #333;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
    --radius-md: 12px;
    --radius-lg: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    margin: 0;
    padding: 20px;
    line-height: 1.6;
}

#app {
    max-width: 900px;
    margin: 0 auto;
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    min-height: 80vh;
}

/* Header */
header {
    padding: 40px 40px 20px;
    text-align: center;
    background: linear-gradient(180deg, #fff 0%, #f9f9f9 100%);
    border-bottom: 1px solid var(--border-color);
}

h1 {
    margin: 0 0 10px;
    font-size: 32px;
    font-weight: 700;
    letter-spacing: -0.5px;
    background: -webkit-linear-gradient(45deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 16px;
    margin-bottom: 30px;
}

/* Tabs */
.tabs {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: -21px; /* Overlap border */
}

.tab-btn {
    padding: 12px 30px;
    background: transparent;
    border: none;
    border-bottom: 3px solid transparent;
    font-size: 16px;
    font-weight: 600;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.3s ease;
}

.tab-btn:hover {
    color: var(--primary-color);
}

.tab-btn.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
}

/* Content */
.content-area {
    padding: 40px;
    flex: 1;
}

.section {
    background: #fff;
    margin-bottom: 30px;
    /* animation: fadeIn 0.4s ease-out; */
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

h2 {
    font-size: 18px;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-secondary);
    margin-top: 0;
    margin-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 10px;
}

/* Controls */
.control-group {
    background: var(--bg-color);
    padding: 20px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    margin-bottom: 20px;
}

.radio-group {
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
}

.radio-option {
    display: flex;
    align-items: center;
    padding: 12px 16px;
    background: #fff;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    cursor: pointer;
    transition: all 0.2s;
}

.radio-option:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-sm);
}

.radio-option input {
    margin-right: 12px;
    accent-color: var(--primary-color);
}

/* File Input Styling */
.file-input-hidden {
    display: none;
}

.file-select-btn {
    display: inline-block;
    width: 100%;
    padding: 12px;
    background: #fff;
    border: 1px dashed var(--border-color);
    border-radius: 8px;
    cursor: pointer;
    text-align: center;
    color: var(--text-secondary);
    transition: all 0.2s;
    box-sizing: border-box;
}

.file-select-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    background: #fcfcfc;
}

.file-info {
    margin-top: 8px;
    font-size: 14px;
    color: var(--text-secondary);
    word-break: break-all;
}

.text-pre-line {
    white-space: pre-line;
}

/* Buttons */
.btn {
    display: block;
    width: 100%;
    padding: 16px;
    font-size: 16px;
    font-weight: 600;
    color: #fff;
    background: var(--primary-color);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s;
    box-shadow: 0 4px 6px rgba(0, 122, 255, 0.2);
}

.btn:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 6px 8px rgba(0, 122, 255, 0.3);
}

.btn:active {
    transform: translateY(1px);
}

.btn:disabled {
    background: #ccc;
    cursor: not-allowed;
    box-shadow: none;
    transform: none;
}

.btn-secondary {
    background: #e5e5ea;
    color: var(--text-primary);
    box-shadow: none;
}

.btn-secondary:hover {
    background: #d1d1d6;
    box-shadow: none;
}

/* Progress Component */
.progress-container {
    background: #fff;
    padding: 20px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    margin-top: 20px;
    box-shadow: var(--shadow-sm);
}

.progress-info {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
    font-size: 14px;
    font-weight: 600;
}

.progress-bar-bg {
    height: 8px;
    background: #e5e5ea;
    border-radius: 4px;
    overflow: hidden;
}

.progress-bar-fill {
    height: 100%;
    background: var(--success-color);
    width: 0;
    transition: width 0.3s ease;
}

.progress-stats {
    margin-top: 8px;
    font-size: 12px;
    color: var(--text-secondary);
    text-align: right;
    font-family: monospace;
}

/* Log Component */
.log-panel {
    margin-top: 30px;
    border-top: 1px solid var(--border-color);
    padding-top: 20px;
}

.log-panel h3 {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 10px;
    font-weight: 600;
}

.log-output {
    background: var(--log-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 15px;
    height: 200px;
    overflow-y: auto;
    font-family: 'SF Mono', 'Menlo', 'Monaco', 'Courier New', monospace;
    font-size: 12px;
}

.log-entry {
    padding: 2px 0;
    border-bottom: 1px solid rgba(0,0,0,0.05);
}

.log-time {
    color: #999;
    margin-right: 8px;
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: #ccc;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #bbb;
}