:root {
    --bg: #F5F7F4;
    --card: #FFFFFF;
    --card2: #F0F4EE;
    --accent: #5B9A4B;
    --accent2: #8CC63F;
    --accent-glow: rgba(91, 154, 75, 0.10);
    --text: #1E2B1A;
    --text-muted: #5A6B54;
    --text-dim: #8C9E85;
    --success: #3DAA5C;
    --error: #D94F4F;
    --warning: #E6A93C;
    --border: #D6DFD2;
    --border-soft: #E8EDE5;
    --sidebar-width: 260px;
}

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

body {
    font-family: 'DM Sans', sans-serif;
    background: var(--bg);
    min-height: 100vh;
    color: var(--text);
}

/* Background texture */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    background:
        radial-gradient(ellipse 80% 50% at 20% 10%, rgba(140, 198, 63, 0.06) 0%, transparent 60%),
        radial-gradient(ellipse 60% 40% at 80% 90%, rgba(91, 154, 75, 0.04) 0%, transparent 60%);
    pointer-events: none;
    z-index: 0;
}

/* ── LAYOUT ── */
.app-container {
    display: flex;
    min-height: 100vh;
    position: relative;
    z-index: 1;
}

/* ── SIDEBAR ── */
.sidebar {
    width: var(--sidebar-width);
    background: var(--card);
    border-right: 1px solid var(--border-soft);
    display: flex;
    flex-direction: column;
    padding: 32px 20px;
    position: sticky;
    top: 0;
    height: 100vh;
    transition: transform 0.3s ease;
}

.sidebar-header {
    margin-bottom: 40px;
    text-align: center;
}

.sidebar-logo {
    width: 120px;
    height: auto;
    display: block;
    margin: 0 auto;
}

.nav-menu {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.nav-item a {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    text-decoration: none;
    color: var(--text-muted);
    font-size: 14px;
    font-weight: 500;
    border-radius: 12px;
    transition: all 0.2s ease;
}

.nav-item a:hover {
    background: var(--card2);
    color: var(--accent);
}

.nav-item.active a {
    background: var(--accent);
    color: #fff;
    box-shadow: 0 4px 12px rgba(91, 154, 75, 0.25);
}

.nav-icon {
    width: 20px;
    height: 20px;
    stroke-width: 1.5;
    fill: none;
    stroke: currentColor;
}

/* ── MAIN CONTENT ── */
.main-content {
    flex: 1;
    padding: 40px 16px 60px;
    display: flex;
    flex-direction: column;
    align-items: center;
    overflow-y: auto;
}

.wrapper {
    width: 100%;
    max-width: 560px;
}

/* ── TOP BAR ── */
.top-bar {
    height: 4px;
    display: flex;
    border-radius: 2px;
    overflow: hidden;
    margin-bottom: 32px;
}

.top-bar span {
    flex: 1;
}

.top-bar span:nth-child(1) {
    background: var(--accent2);
}

.top-bar span:nth-child(2) {
    background: var(--accent);
}

.top-bar span:nth-child(3) {
    background: #3B7A2E;
}

/* ── HEADER ── */
.header {
    text-align: center;
    margin-bottom: 32px;
}

.logo-svg {
    display: block;
    margin: 0 auto 12px;
    width: 140px;
    height: auto;
}

.header-sub {
    font-family: 'DM Sans', sans-serif;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-muted);
    letter-spacing: 0.5px;
    text-transform: uppercase;
    margin-bottom: 6px;
}

.header-title {
    font-family: 'DM Serif Display', serif;
    font-size: 36px;
    color: var(--text);
    line-height: 1.1;
    margin-bottom: 8px;
}

.header-desc {
    font-size: 14px;
    color: var(--text-dim);
    font-weight: 300;
}

/* ── DIVIDER ── */
.divider {
    height: 1px;
    background: var(--border-soft);
    margin: 0 0 24px;
}

/* ── CARD ── */
.card {
    background: var(--card);
    border: 1px solid var(--border-soft);
    border-radius: 16px;
    padding: 28px;
    margin-bottom: 20px;
    box-shadow: 0 2px 20px rgba(91, 154, 75, 0.06);
}

.section-label {
    font-size: 10px;
    font-weight: 600;
    letter-spacing: 1.5px;
    text-transform: uppercase;
    color: var(--text-dim);
    margin-bottom: 12px;
}

/* ── DROP ZONE ── */
.drop-zone {
    background: var(--card2);
    border: 1.5px dashed var(--border);
    border-radius: 12px;
    height: 120px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.25s ease;
    gap: 8px;
    position: relative;
    overflow: hidden;
}

.drop-zone:hover,
.drop-zone.hover {
    border-color: var(--accent);
    background: rgba(91, 154, 75, 0.05);
}

.drop-zone.selected {
    border-color: var(--accent2);
    border-style: solid;
    background: rgba(140, 198, 63, 0.07);
}

.drop-zone input[type="file"] {
    position: absolute;
    inset: 0;
    opacity: 0;
    cursor: pointer;
    font-size: 0;
}

.drop-icon {
    font-size: 24px;
    transition: transform 0.2s;
}

.drop-zone:hover .drop-icon {
    transform: translateY(-2px);
}

.drop-zone.selected .drop-icon {
    color: var(--success);
}

.drop-text {
    font-size: 13px;
    color: var(--text-muted);
    text-align: center;
    line-height: 1.5;
    pointer-events: none;
}

.file-path {
    font-family: 'DM Mono', monospace;
    font-size: 11px;
    color: var(--text-dim);
    margin-top: 10px;
    word-break: break-all;
}

.inner-divider {
    height: 1px;
    background: var(--border-soft);
    margin: 20px 0;
}

/* ── OUTPUT ROW ── */
.output-row {
    display: flex;
    align-items: center;
    gap: 12px;
}

.output-text {
    flex: 1;
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 400;
}

.output-text.custom {
    color: var(--text);
}

.output-select-btn {
    font-size: 12px;
    color: var(--accent);
    font-weight: 600;
    cursor: pointer;
    white-space: nowrap;
    background: none;
    border: none;
    padding: 4px 0;
    font-family: inherit;
}

.output-select-btn:hover {
    text-decoration: underline;
}

/* ── MAIN BUTTON ── */
.btn-wrap {
    display: flex;
    justify-content: center;
    margin-bottom: 20px;
}

.btn-split {
    background: var(--accent);
    color: #fff;
    border: none;
    border-radius: 14px;
    padding: 16px 40px;
    font-family: 'DM Sans', sans-serif;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    letter-spacing: 0.3px;
    box-shadow: 0 4px 20px rgba(91, 154, 75, 0.3);
    position: relative;
    overflow: hidden;
}

.btn-split::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.1), transparent);
    pointer-events: none;
}

.btn-split:hover:not(:disabled) {
    background: #4A8A3C;
    transform: translateY(-1px);
    box-shadow: 0 6px 28px rgba(91, 154, 75, 0.35);
}

.btn-split:active:not(:disabled) {
    transform: translateY(0);
}

.btn-split:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

/* ── PROGRESS ── */
.progress-wrap {
    margin-bottom: 8px;
}

.progress-track {
    background: var(--card2);
    border-radius: 99px;
    height: 5px;
    overflow: hidden;
    margin-bottom: 8px;
}

.progress-fill {
    background: linear-gradient(90deg, var(--accent2), var(--accent));
    height: 100%;
    border-radius: 99px;
    width: 0%;
    transition: width 0.3s ease;
}

.progress-label {
    font-size: 12px;
    color: var(--text-dim);
    text-align: center;
    min-height: 18px;
}

.progress-label.success {
    color: var(--success);
    font-weight: 500;
}

/* ── RESULTS ── */
.results-card {
    background: var(--card);
    border: 1px solid var(--border-soft);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 2px 20px rgba(91, 154, 75, 0.06);
}

.results-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 20px;
    border-bottom: 1px solid var(--border-soft);
}

.results-title {
    font-size: 10px;
    font-weight: 600;
    letter-spacing: 1.5px;
    text-transform: uppercase;
    color: var(--text-dim);
}

.results-count {
    font-size: 12px;
    font-weight: 600;
    color: var(--accent);
}

.results-body {
    height: 160px;
    overflow-y: auto;
    padding: 8px 0;
}

.results-body::-webkit-scrollbar {
    width: 4px;
}

.results-body::-webkit-scrollbar-track {
    background: transparent;
}

.results-body::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 4px;
}

.result-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 5px 20px;
    font-family: 'DM Mono', monospace;
    font-size: 11px;
    color: var(--text-muted);
    animation: fadeSlide 0.2s ease forwards;
}

@keyframes fadeSlide {
    from {
        opacity: 0;
        transform: translateX(-4px);
    }

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

.result-check {
    color: var(--success);
    font-size: 12px;
}

.placeholder-msg {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    color: var(--text-dim);
    font-weight: 300;
}

.error-msg {
    padding: 20px;
    color: var(--error);
    font-size: 13px;
    text-align: center;
}

/* ── DOWNLOAD NOTICE ── */
.download-notice {
    text-align: center;
    font-size: 12px;
    color: var(--text-dim);
    margin-top: 16px;
    padding: 12px 20px;
    background: var(--card);
    border: 1px solid var(--border-soft);
    border-radius: 12px;
    line-height: 1.6;
}

.download-notice strong {
    color: var(--accent);
}

/* ── MOBILE NAVBAR ── */
.mobile-header {
    display: none;
    background: var(--card);
    border-bottom: 1px solid var(--border-soft);
    padding: 12px 20px;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 100;
}

.menu-toggle {
    background: none;
    border: none;
    color: var(--text);
    cursor: pointer;
    font-size: 24px;
}

/* Responsive */
@media (max-width: 768px) {
    .app-container {
        flex-direction: column;
    }

    .sidebar {
        position: fixed;
        left: 0;
        top: 0;
        bottom: 0;
        transform: translateX(-100%);
        z-index: 1000;
        box-shadow: 20px 0 50px rgba(0, 0, 0, 0.1);
    }

    .sidebar.open {
        transform: translateX(0);
    }

    .mobile-header {
        display: flex;
    }

    .sidebar-header {
        display: none;
    }
    
    .sidebar-overlay {
        display: none;
        position: fixed;
        inset: 0;
        background: rgba(0, 0, 0, 0.2);
        backdrop-filter: blur(4px);
        z-index: 999;
    }
    
    .sidebar-overlay.open {
        display: block;
    }
}