:root {
    --primary-color: #0f172a;
    --accent-color: #2563eb;
    --bg-color: #f8fafc;
    --surface-color: #ffffff;
    --text-main: #334155;
    --text-muted: #64748b;
    --border-color: #e2e8f0;
    --danger-bg: #fef2f2;
    --danger-border: #fca5a5;
    --success-bg: #f0fdf4;
    --success-border: #86efac;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
}

header {
    background-color: var(--primary-color);
    color: white;
    padding: 1.5rem 2rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

header h1 {
    font-size: 1.5rem;
    margin-bottom: 0.25rem;
}

header p {
    color: #cbd5e1;
    font-size: 0.9rem;
}

.container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    padding: 2rem;
    max-width: 1400px;
    margin: 0 auto;
    height: calc(100vh - 85px);
}

.input-section, .results-section {
    background: var(--surface-color);
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    display: flex;
    flex-direction: column;
}

.form-group {
    margin-bottom: 1.5rem;
    display: flex;
    flex-direction: column;
}

label {
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

select, textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 1rem;
}

select:focus, textarea:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

textarea {
    flex-grow: 1;
    min-height: 400px;
    resize: vertical;
}

.help-text {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 0.5rem;
    font-style: italic;
}

.button-group {
    display: flex;
    gap: 1rem;
    margin-top: auto;
}

button {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 6px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 1rem;
}

.btn-primary {
    background-color: var(--accent-color);
    color: white;
    flex-grow: 1;
}

.btn-primary:hover { background-color: #1d4ed8; }

.btn-secondary {
    background-color: #e2e8f0;
    color: var(--text-main);
}

.btn-secondary:hover { background-color: #cbd5e1; }

.results-section h2 {
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-color);
}

.hidden { display: none !important; }

.result-block {
    background: #f8fafc;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 1rem;
    margin-bottom: 1rem;
}

.result-block h3 {
    font-size: 1rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.warning-block {
    background: var(--danger-bg);
    border-color: var(--danger-border);
}

.warning-block h3 { color: #b91c1c; }

.success-block {
    background: var(--success-bg);
    border-color: var(--success-border);
}

.success-block h3 { color: #15803d; }

.result-text p { margin-bottom: 0.5rem; }
.result-text ul { padding-left: 1.5rem; margin-bottom: 0.5rem; }

/* Loading Spinner */
#loading-state {
    text-align: center;
    padding: 3rem 0;
}
.spinner {
    border: 4px solid rgba(0, 0, 0, 0.1);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border-left-color: var(--accent-color);
    animation: spin 1s linear infinite;
    margin: 0 auto 1rem;
}
@keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }

/* Responsive */
@media (max-width: 900px) {
    .container { grid-template-columns: 1fr; height: auto; }
    textarea { min-height: 250px; }
}
/* Add to bottom of style.css */
.file-drop-area {
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    padding: 2rem 1rem;
    text-align: center;
    background-color: #f8fafc;
    position: relative;
    transition: all 0.2s ease;
    cursor: pointer;
    flex-grow: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 150px;
}

.file-drop-area:hover, .file-drop-area.dragover {
    border-color: var(--accent-color);
    background-color: #eff6ff;
}

.file-drop-area input[type="file"] {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    opacity: 0;
    cursor: pointer;
}

#file-status {
    color: var(--text-muted);
    font-weight: 500;
}

.file-status-success {
    color: #047857 !important;
    font-weight: 600 !important;
}