/* ============ Reset & Base ============ */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #6C5CE7;
    --primary-hover: #5A4BD1;
    --primary-light: #A29BFE;
    --success: #00B894;
    --success-hover: #00A381;
    --danger: #FF7675;
    --danger-bg: #FFF5F5;
    --warning: #FDCB6E;
    --bg: #F8F9FF;
    --card-bg: #FFFFFF;
    --text: #2D3436;
    --text-secondary: #636E72;
    --border: #DFE6E9;
    --shadow: 0 2px 16px rgba(108, 92, 231, 0.08);
    --radius: 12px;
    --transition: 0.25s ease;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
    background: linear-gradient(135deg, #E8ECFF 0%, #F0E6FF 50%, #FFE8F0 100%);
    color: var(--text);
    min-height: 100vh;
    line-height: 1.6;
}

.hidden { display: none !important; }

/* ============ Container ============ */
.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 40px 20px 60px;
}

/* ============ Auth Page ============ */
.auth-page {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

.auth-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 36px;
    width: 100%;
    max-width: 420px;
    border: 1px solid var(--border);
}

.auth-tabs {
    display: flex;
    margin-bottom: 28px;
    border-bottom: 2px solid var(--border);
}

.auth-tab {
    flex: 1;
    padding: 10px 0;
    border: none;
    background: none;
    font-size: 1rem;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
}

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

.auth-form .form-group {
    margin-bottom: 18px;
}

.auth-form label {
    display: block;
    font-weight: 500;
    margin-bottom: 6px;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.auth-form input {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--border);
    border-radius: 8px;
    font-size: 1rem;
    transition: var(--transition);
    outline: none;
}

.auth-form input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(108, 92, 231, 0.1);
}

.auth-error {
    color: var(--danger);
    font-size: 0.85rem;
    margin-bottom: 12px;
    padding: 8px 12px;
    background: var(--danger-bg);
    border-radius: 6px;
}

/* ============ Header ============ */
.header-row {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 20px;
}

.header-row h1 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 4px;
}

.subtitle {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.user-menu {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-top: 4px;
}

.user-name {
    font-weight: 500;
    color: var(--text);
    font-size: 0.9rem;
}

.btn-sm {
    padding: 5px 14px !important;
    font-size: 0.8rem !important;
}

.main-nav {
    display: flex;
    gap: 0;
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    overflow: hidden;
    margin-bottom: 24px;
}

.nav-btn {
    flex: 1;
    padding: 12px 24px;
    border: none;
    background: none;
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
    position: relative;
}

.nav-btn:hover {
    color: var(--primary);
    background: #F8F7FF;
}

.nav-btn.active {
    color: var(--primary);
    background: #F0EDFF;
    font-weight: 600;
}

.nav-btn.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--primary);
}

/* ============ Card ============ */
.card {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 28px;
    margin-bottom: 20px;
    border: 1px solid var(--border);
    transition: var(--transition);
}

.card h2 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 18px;
    color: var(--text);
}

/* ============ Drop Zone ============ */
.drop-zone {
    border: 2px dashed var(--primary-light);
    border-radius: var(--radius);
    padding: 40px 20px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    background: #F8F7FF;
}

.drop-zone:hover, .drop-zone.drag-over {
    border-color: var(--primary);
    background: #F0EDFF;
}

.drop-zone-content p {
    margin-top: 10px;
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.upload-icon {
    color: var(--primary-light);
}

.or-divider {
    font-size: 0.85rem;
    color: var(--border);
    margin: 16px 0;
}

.hint {
    font-size: 0.8rem !important;
    color: #B2BEC3 !important;
    margin-top: 14px !important;
}

/* ============ Buttons ============ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
}

.btn-primary {
    background: var(--primary);
    color: #fff;
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(108, 92, 231, 0.3);
}

.btn-success {
    background: var(--success);
    color: #fff;
}

.btn-success:hover {
    background: var(--success-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 184, 148, 0.3);
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 1.5px solid var(--primary);
}

.btn-outline:hover {
    background: #F0EDFF;
}

.btn-danger {
    background: transparent;
    color: var(--danger);
    border: 1.5px solid var(--danger);
}

.btn-danger:hover {
    background: var(--danger-bg);
}

.btn-lg {
    padding: 14px 32px;
    font-size: 1.05rem;
    border-radius: 10px;
    width: 100%;
    margin-top: 16px;
}

/* ============ Upload Info ============ */
.upload-info {
    margin-top: 16px;
    padding: 14px 18px;
    background: #F0FFF4;
    border: 1px solid #B2F0D0;
    border-radius: 8px;
}

.file-info {
    display: flex;
    align-items: center;
    gap: 10px;
}

.file-icon {
    font-size: 1.4rem;
}

#file-name {
    font-weight: 500;
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.duration-badge {
    background: var(--success);
    color: #fff;
    padding: 3px 10px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    white-space: nowrap;
}

/* ============ Config Form ============ */
.config-form .form-group {
    margin-bottom: 16px;
}

.config-form label {
    display: block;
    font-weight: 500;
    margin-bottom: 6px;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

#segment-duration {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--border);
    border-radius: 8px;
    font-size: 1rem;
    transition: var(--transition);
    outline: none;
}

#segment-duration:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(108, 92, 231, 0.1);
}

.quick-buttons {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
}

.quick-label {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-right: 4px;
}

.quick-buttons .btn-outline {
    padding: 6px 14px;
    font-size: 0.85rem;
    border-radius: 20px;
}

.quick-buttons .btn-outline.active {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

.preview-info {
    padding: 12px 16px;
    background: #FFF9E6;
    border-radius: 8px;
    margin-top: 12px;
}

.preview-info p {
    font-size: 0.9rem;
    margin-bottom: 4px;
}

.preview-info p:last-child {
    margin-bottom: 0;
}

/* ============ Progress ============ */
.progress-container {
    margin-bottom: 20px;
}

.progress-bar {
    height: 8px;
    background: var(--border);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 10px;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--primary-light));
    border-radius: 4px;
    width: 0%;
    transition: width 0.5s ease;
}

#progress-text {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.spinner {
    width: 36px;
    height: 36px;
    border: 3px solid var(--border);
    border-top-color: var(--primary);
    border-radius: 50%;
    margin: 0 auto;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ============ Result ============ */
.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
    flex-wrap: wrap;
    gap: 10px;
}

#result-summary {
    font-weight: 500;
    color: var(--text-secondary);
}

.segment-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 16px;
    max-height: 320px;
    overflow-y: auto;
}

.segment-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 16px;
    background: #F8F9FF;
    border-radius: 8px;
    border: 1px solid var(--border);
    transition: var(--transition);
}

.segment-item:hover {
    background: #F0EDFF;
}

.segment-name {
    font-weight: 500;
    font-size: 0.9rem;
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    margin-right: 12px;
}

.segment-download {
    padding: 6px 14px;
    font-size: 0.85rem;
}

.action-buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.action-buttons .btn {
    flex: 1;
    min-width: 140px;
}

/* ============ Error ============ */
.error-card {
    background: var(--danger-bg);
    border-color: #FED7D7;
}

.error-card h2 {
    color: var(--danger);
}

#error-message {
    color: #C53030;
    margin-bottom: 16px;
    font-size: 0.9rem;
}

/* ============ History Table ============ */
.history-filters {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
    gap: 12px;
    flex-wrap: wrap;
}

.filter-select {
    padding: 8px 14px;
    border: 1.5px solid var(--border);
    border-radius: 8px;
    font-size: 0.9rem;
    color: var(--text);
    background: #fff;
    outline: none;
    cursor: pointer;
}

.filter-select:focus {
    border-color: var(--primary);
}

.history-table-wrap {
    overflow-x: auto;
    margin-bottom: 16px;
}

.history-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.88rem;
}

.history-table th {
    text-align: left;
    padding: 10px 12px;
    background: #F8F9FF;
    color: var(--text-secondary);
    font-weight: 600;
    border-bottom: 2px solid var(--border);
    white-space: nowrap;
}

.history-table td {
    padding: 10px 12px;
    border-bottom: 1px solid var(--border);
    vertical-align: middle;
}

.history-table tbody tr:hover {
    background: #F8F7FF;
}

.filename-cell {
    max-width: 200px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.status-badge {
    display: inline-block;
    padding: 2px 10px;
    border-radius: 20px;
    font-size: 0.78rem;
    font-weight: 600;
    white-space: nowrap;
}

.status-badge.uploaded { background: #E8ECFF; color: #6C5CE7; }
.status-badge.splitting { background: #FFF9E6; color: #E17055; }
.status-badge.completed { background: #F0FFF4; color: #00B894; }
.status-badge.failed { background: var(--danger-bg); color: #D63031; }

.history-actions {
    display: flex;
    gap: 6px;
}

.history-actions .btn {
    padding: 4px 10px;
    font-size: 0.78rem;
    border-radius: 6px;
}

.history-empty {
    text-align: center;
    padding: 40px 20px;
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Pagination */
.history-pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 6px;
    margin-top: 16px;
}

.page-btn {
    padding: 6px 12px;
    border: 1.5px solid var(--border);
    border-radius: 6px;
    background: #fff;
    color: var(--text);
    font-size: 0.85rem;
    cursor: pointer;
    transition: var(--transition);
}

.page-btn:hover:not(:disabled) {
    border-color: var(--primary);
    color: var(--primary);
}

.page-btn.active {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

.page-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.page-info {
    font-size: 0.85rem;
    color: var(--text-secondary);
    padding: 0 8px;
}

/* ============ Responsive ============ */
@media (max-width: 640px) {
    .container {
        padding: 16px 10px 40px;
    }

    .card {
        padding: 20px 14px;
    }

    header h1 {
        font-size: 1.5rem;
    }

    .header-row {
        flex-direction: column;
        gap: 10px;
    }

    .result-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .history-table th, .history-table td {
        padding: 8px 6px;
        font-size: 0.8rem;
    }
}