:root {
    --primary-color: #0056D2;
    --primary-hover: #0046a8;
    --bg-color: #f3f5fa;
    --card-bg: #f5f7fa;
    --text-main: #111827;
    --text-muted: #6b7280;
    --border-color: #e5e7eb;
    --border-dash: #a5b4fc;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header & Topbar */
.topbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 32px;
    background-color: white;
    box-shadow: var(--shadow-sm);
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background-color: var(--primary-color);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.logo-text h1 {
    font-size: 18px;
    font-weight: 700;
    color: var(--primary-color);
    line-height: 1.2;
}

.logo-text p {
    font-size: 10px;
    font-weight: 600;
    color: var(--text-muted);
    letter-spacing: 1px;
}

/* Navigation Buttons */
.tools-nav {
    display: flex;
    gap: 12px;
    background-color: #f8fafc;
    padding: 4px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
}

.nav-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    border: none;
    background: transparent;
    color: var(--text-muted);
    font-size: 14px;
    font-weight: 500;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.nav-btn:hover {
    color: var(--primary-color);
    background-color: #f1f5f9;
}

.nav-btn.active {
    background-color: white;
    color: var(--primary-color);
    box-shadow: var(--shadow-sm);
}

/* Main Content Area */
.main-content {
    flex: 1;
    max-width: 1000px;
    width: 100%;
    margin: 40px auto;
    padding: 0 24px;
}

.view-section {
    display: none;
    animation: fadeIn 0.3s ease-out forwards;
}

.view-section.active {
    display: block;
}

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

.header-title {
    margin-bottom: 32px;
}

.header-title h2 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 8px;
}

.header-title p {
    font-size: 16px;
    color: var(--text-muted);
}

/* Upload Zones */
.upload-container {
    display: flex;
    gap: 24px;
    margin-bottom: 32px;
}

.upload-zone {
    flex: 1;
}

.zone-header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 12px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.drop-area {
    background-color: var(--card-bg);
    border: 2px dashed var(--border-dash);
    border-radius: 12px;
    padding: 48px 24px;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s ease;
}

.drop-area:hover {
    border-color: var(--primary-color);
    background-color: #eef2ff;
}

.drop-area.dragover {
    border-color: var(--primary-color);
    background-color: #eef2ff;
    transform: scale(1.02);
}

.drop-area.has-file {
    border-style: solid;
    border-color: #10b981;
    background-color: #ecfdf5;
}

.upload-icon {
    width: 32px;
    height: 32px;
    color: #93c5fd;
    margin-bottom: 16px;
}

.drop-area.has-file .upload-icon {
    color: #10b981;
}

.upload-text {
    font-size: 15px;
    font-weight: 500;
    color: var(--primary-color);
    margin-bottom: 8px;
}

.drop-area.has-file .upload-text {
    color: #059669;
}

.upload-subtext {
    font-size: 11px;
    font-weight: 600;
    color: var(--text-muted);
}

/* Primary Button */
.primary-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    padding: 16px 32px;
    font-size: 16px;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    width: auto;
    min-width: 300px;
}

.primary-btn:hover:not(:disabled) {
    background-color: var(--primary-hover);
    box-shadow: var(--shadow-md);
}

.primary-btn:disabled {
    background-color: #94a3b8;
    cursor: not-allowed;
    opacity: 0.7;
}

/* Development Box */
.development-box {
    background-color: white;
    border-radius: 12px;
    padding: 48px;
    text-align: center;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    margin-top: 24px;
}

.development-box h3 {
    margin: 16px 0 8px;
    font-size: 20px;
    color: var(--text-main);
}

.development-box p {
    color: var(--text-muted);
}

/* Footer */
.footer {
    text-align: center;
    padding: 24px;
    font-size: 11px;
    font-weight: 600;
    color: var(--text-muted);
    letter-spacing: 1px;
    margin-top: auto;
}

/* Docx Convert View Styles */
.settings-container {
    display: flex;
    gap: 20px;
    margin-bottom: 24px;
    background-color: white;
    padding: 20px;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}

.input-group {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.input-group label {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-main);
}

.input-group input,
.input-group textarea {
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-family: inherit;
    font-size: 14px;
    background-color: var(--card-bg);
    transition: border-color 0.2s;
    outline: none;
}

.input-group input:focus,
.input-group textarea:focus {
    border-color: var(--primary-color);
    background-color: white;
}

.docx-workspace {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-bottom: 24px;
    height: 500px;
}

.workspace-col {
    display: flex;
    flex-direction: column;
    background-color: white;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
    overflow: hidden;
}

.col-header {
    padding: 16px;
    background-color: #f8fafc;
    border-bottom: 1px solid var(--border-color);
}

.col-header h3 {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-main);
    margin: 0;
}

#raw-exam-input {
    flex: 1;
    border: none;
    padding: 16px;
    font-family: monospace;
    font-size: 14px;
    resize: none;
    outline: none;
    background-color: white;
}

.chatbox-output {
    flex: 1;
    padding: 16px;
    overflow-y: auto;
    background-color: #f1f5f9;
    font-family: monospace;
    font-size: 14px;
    line-height: 1.6;
    color: #1e293b;
    white-space: pre-wrap;
    word-wrap: break-word;
}

.placeholder-text {
    color: var(--text-muted);
    font-style: italic;
    text-align: center;
    margin-top: 40px;
}

.action-bar {
    display: flex;
    justify-content: flex-end;
}