:root {
    --primary-color: #036B3F;
    --primary-hover: #025a34;
    --primary-light: #e8f5e9;
    --secondary-color: #5c6bc0;
    --success-color: #43a047;
    --danger-color: #e53935;
    --warning-color: #fb8c00;
    --bg-color: #f8f9fa;
    --card-bg: #ffffff;
    --text-color: #2d3436;
    --text-secondary: #636e72;
    --border-color: #dfe6e9;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    --shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.12);
    --radius: 12px;
    --radius-sm: 8px;
}

[data-theme="dark"] {
    --primary-color: #4caf50;
    --primary-hover: #43a047;
    --primary-light: #1b3d2f;
    --bg-color: #121212;
    --card-bg: #1e1e1e;
    --text-color: #e0e0e0;
    --text-secondary: #9e9e9e;
    --border-color: #333333;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    --shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.4);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.7;
    transition: background-color 0.3s, color 0.3s;
    background-image: linear-gradient(135deg, var(--bg-color) 0%, #e8f5e9 100%);
    min-height: 100vh;
}

[data-theme="dark"] body {
    background-image: linear-gradient(135deg, var(--bg-color) 0%, #1a2f1a 100%);
}

input, textarea, select, button, label, span, p, div, h1, h2, h3, h4, h5, h6, a, li, td, th {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif !important;
}

::placeholder {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif !important;
}

::-webkit-input-placeholder {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif !important;
}

::-moz-placeholder {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif !important;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
    padding-bottom: 100px;
}

/* 건국대학교 로고 배너 */
.logo-banner {
    text-align: center;
    margin-bottom: 0;
    padding: 20px 15px;
    background: linear-gradient(135deg, #036B3F 0%, #024d2d 100%);
    border-radius: var(--radius) var(--radius) 0 0;
    box-shadow: var(--shadow);
}

.ku-logo {
    max-width: 220px;
    height: auto;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 18px 25px;
    margin-bottom: 25px;
    background: var(--card-bg);
    color: var(--text-color);
    border-radius: 0 0 var(--radius) var(--radius);
    position: relative;
    box-shadow: var(--shadow);
    border-top: 3px solid var(--primary-color);
}

header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    text-align: center;
    flex: 1;
    color: var(--primary-color);
    letter-spacing: -0.5px;
}

.header-left {
    display: flex;
    align-items: center;
    min-width: 150px;
}

.header-controls {
    display: flex;
    gap: 10px;
    align-items: center;
    min-width: 150px;
    justify-content: flex-end;
}

.user-info {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--primary-light);
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    border: 1px solid var(--border-color);
}

.user-info #userName {
    max-width: 120px;
    overflow: hidden;
    font-weight: 600;
    color: var(--primary-color);
    text-overflow: ellipsis;
    white-space: nowrap;
}

.icon-btn {
    background: var(--primary-light);
    border: 1px solid var(--border-color);
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
}

.icon-btn:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(3, 107, 63, 0.3);
}

.section {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 25px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
}

.section:hover {
    box-shadow: var(--shadow-hover);
}

/* 아코디언 스타일 */
.section.accordion {
    padding: 0;
    overflow: hidden;
}

.accordion-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 25px;
    cursor: pointer;
    background: var(--card-bg);
    transition: all 0.3s ease;
    user-select: none;
    border-left: 4px solid transparent;
}

.accordion-header:hover {
    background: var(--primary-light);
    border-left-color: var(--primary-color);
}

.accordion.open .accordion-header {
    background: var(--primary-light);
    border-left-color: var(--primary-color);
}

.accordion-header h2 {
    margin: 0;
    padding: 0;
    border: none;
    flex-shrink: 0;
}

.accordion-summary {
    flex: 1;
    margin: 0 15px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    max-width: 500px;
}

.accordion-summary:empty {
    display: none;
}

.accordion-summary .summary-tag {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 0.75rem;
    margin-right: 5px;
}

.accordion-summary .summary-text {
    color: var(--text-secondary);
}

.accordion-icon {
    font-size: 1.8rem;
    font-weight: 300;
    color: var(--primary-color);
    transition: transform 0.3s ease;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.accordion.open .accordion-icon {
    transform: rotate(45deg);
}

.accordion-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease-out, padding 0.3s ease;
    padding: 0 25px;
}

.accordion.open .accordion-content {
    max-height: 5000px;
    padding: 0 25px 25px 25px;
    transition: max-height 0.6s ease-in, padding 0.3s ease;
}

.section h2 {
    color: var(--primary-color);
    font-size: 1.4rem;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--primary-color);
}

.section h3 {
    font-size: 1.1rem;
    margin-bottom: 15px;
    color: var(--text-color);
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
    color: var(--text-secondary);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 14px 16px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: var(--card-bg);
    color: var(--text-color);
    transition: all 0.3s ease;
}

.form-group input:hover,
.form-group select:hover,
.form-group textarea:hover {
    border-color: var(--primary-color);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(3, 107, 63, 0.15);
    background: var(--primary-light);
}

.form-group small {
    display: block;
    margin-top: 5px;
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

hr {
    border: none;
    border-top: 1px solid var(--border-color);
    margin: 20px 0;
}

.input-area,
.result-area {
    margin-bottom: 15px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-hover) 100%);
    color: white;
    border: none;
    padding: 12px 28px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px rgba(3, 107, 63, 0.3);
    text-transform: none;
    letter-spacing: 0.3px;
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-hover) 0%, #013d24 100%);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(3, 107, 63, 0.4);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--secondary-color);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 0.95rem;
    transition: background 0.3s;
}

.btn-secondary:hover {
    background: #5a6268;
}

.btn-danger {
    background: var(--danger-color);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 1rem;
    transition: background 0.3s;
}

.btn-danger:hover {
    background: #c82333;
}

.btn-delete {
    background: var(--danger-color);
    color: white;
    border: none;
    padding: 10px 18px;
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 0.95rem;
    font-weight: 500;
    transition: background 0.3s, transform 0.2s;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.15);
}

.btn-delete:hover {
    background: #c82333;
    transform: translateY(-1px);
}

.btn-ai {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    transition: transform 0.2s, box-shadow 0.3s;
}

.btn-ai:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.item-list {
    min-height: 50px;
}

.placeholder-text {
    color: var(--text-secondary);
    font-style: italic;
    text-align: center;
    padding: 20px;
}

.item-card {
    background: var(--card-bg);
    border-radius: var(--radius-sm);
    padding: 18px 20px;
    margin-bottom: 12px;
    position: relative;
    border: 1px solid var(--border-color);
    border-left: 4px solid var(--primary-color);
    transition: all 0.3s ease;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.04);
}

.item-card:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    transform: translateX(4px);
}

.item-card h4 {
    color: var(--primary-color);
    margin-bottom: 10px;
    font-size: 1.1rem;
    font-weight: 600;
}

.item-card p {
    margin-bottom: 6px;
    line-height: 1.6;
    font-size: 0.95rem;
}

.item-card .date-range {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

.item-actions {
    position: absolute;
    top: 10px;
    right: 10px;
    display: flex;
    gap: 8px;
}

.item-card .edit-item,
.item-card .delete-item {
    background: var(--danger-color);
    color: white;
    border: none;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.3s, transform 0.2s;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
}

.item-card .edit-item {
    background: var(--primary-color);
}

.item-card .edit-item:hover {
    background: var(--primary-hover);
    transform: scale(1.1);
}

.item-card .delete-item:hover {
    background: #c82333;
    transform: scale(1.1);
}

.skill-subsection {
    margin-bottom: 20px;
}

.skill-list {
    margin-bottom: 15px;
}

.skill-item {
    display: flex;
    gap: 10px;
    margin-bottom: 10px;
    align-items: center;
    flex-wrap: wrap;
}

.skill-item input,
.skill-item select {
    flex: 1;
    min-width: 120px;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    font-size: 1rem;
    background: var(--card-bg);
    color: var(--text-color);
}

.ai-controls {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.cover-letter-content {
    background: var(--bg-color);
    border-radius: var(--radius);
    padding: 20px;
    min-height: 200px;
    line-height: 1.8;
}

.cover-letter-content p {
    margin-bottom: 10px;
}

.cover-letter-edit {
    width: 100%;
    padding: 20px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    font-size: 1rem;
    line-height: 1.8;
    background: var(--card-bg);
    color: var(--text-color);
    resize: vertical;
}

.btn-group {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.btn-row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    align-items: center;
}

.btn-row h4 {
    width: 100%;
    margin-bottom: 5px;
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.danger-zone {
    padding-top: 20px;
    border-top: 1px solid var(--danger-color);
}

.save-status {
    position: fixed;
    bottom: 80px;
    right: 20px;
    background: var(--success-color);
    color: white;
    padding: 10px 20px;
    border-radius: var(--radius);
    display: none;
    animation: fadeIn 0.3s;
    z-index: 1000;
}

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

footer {
    text-align: center;
    padding: 30px 20px;
    color: var(--text-secondary);
    font-size: 0.9rem;
    background: var(--card-bg);
    border-radius: var(--radius);
    margin-top: 30px;
    box-shadow: var(--shadow);
    border-top: 3px solid var(--primary-color);
}

footer p:first-child {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 5px;
}

.mobile-nav {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--card-bg);
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    padding: 10px 0;
}

.mobile-nav .nav-item {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 0.75rem;
    padding: 8px 4px;
    cursor: pointer;
    transition: color 0.3s;
}

.mobile-nav .nav-item.active {
    color: var(--primary-color);
}

.mobile-nav .nav-item span {
    font-size: 0.7rem;
}

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 2000;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.modal.show {
    display: flex;
}

.modal-content {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 30px;
    max-width: 600px;
    width: 100%;
    max-height: 80vh;
    overflow-y: auto;
    position: relative;
}

.close-btn {
    position: absolute;
    top: 15px;
    right: 20px;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    transition: color 0.3s;
}

.close-btn:hover {
    color: var(--text-color);
}

.version-info h4 {
    color: var(--primary-color);
    margin: 20px 0 10px;
}

.version-number {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--primary-color);
}

.version-item {
    background: var(--bg-color);
    border-radius: var(--radius);
    padding: 15px;
    margin-bottom: 15px;
}

.version-header {
    font-weight: 600;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.version-header span {
    font-weight: normal;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.version-item h5 {
    margin-bottom: 10px;
}

.version-item ul {
    list-style: none;
    padding-left: 10px;
}

.version-item li {
    margin-bottom: 5px;
    font-size: 0.9rem;
}

.file-preview {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 10px;
}

.file-preview-item {
    background: var(--bg-color);
    padding: 8px 12px;
    border-radius: var(--radius);
    font-size: 0.85rem;
    display: flex;
    align-items: center;
    gap: 8px;
}

.file-preview-item a {
    color: var(--primary-color);
    text-decoration: none;
}

.file-preview-item a:hover {
    text-decoration: underline;
}

@media (max-width: 768px) {
    .container {
        padding: 10px;
        padding-bottom: 120px;
    }

    header {
        padding: 20px 10px;
    }

    header h1 {
        font-size: 1.3rem;
        padding-right: 80px;
    }

    header {
        flex-wrap: wrap;
        padding: 15px;
        gap: 10px;
    }

    header h1 {
        order: -1;
        width: 100%;
        font-size: 1.4rem;
        margin-bottom: 10px;
    }

    .header-left {
        min-width: auto;
    }

    .header-controls {
        min-width: auto;
    }

    .section {
        padding: 15px;
    }

    .section.accordion {
        padding: 0;
    }

    .accordion-header {
        padding: 15px;
        flex-wrap: nowrap;
    }

    .accordion-header h2 {
        font-size: 1.1rem;
        flex-shrink: 1;
        min-width: 0;
    }

    .accordion-summary {
        display: none;
    }

    .accordion-icon {
        font-size: 1.5rem;
        flex-shrink: 0;
    }

    .accordion-content {
        padding: 0 15px;
    }

    .accordion.open .accordion-content {
        padding: 0 15px 15px 15px;
    }

    .section h2 {
        font-size: 1.2rem;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .skill-item {
        flex-direction: column;
    }

    .item-actions {
        top: 8px;
        right: 8px;
        gap: 5px;
    }

    .item-card .edit-item,
    .item-card .delete-item {
        width: 28px;
        height: 28px;
        font-size: 0.9rem;
    }

    .skill-item input,
    .skill-item select,
    .skill-item button {
        width: 100%;
    }

    .btn-row {
        flex-direction: column;
    }

    .btn-row button {
        width: 100%;
    }

    .mobile-nav {
        display: flex;
    }

    .ai-controls {
        flex-direction: column;
    }

    .ai-controls button {
        width: 100%;
    }
}

@media (max-width: 480px) {
    header h1 {
        font-size: 1.1rem;
    }

    .logo-banner {
        padding: 10px;
        margin-bottom: 15px;
    }

    .ku-logo {
        max-width: 180px;
    }

    .accordion-header h2 {
        font-size: 1rem;
    }

    .accordion-icon {
        font-size: 1.3rem;
        width: 25px;
        height: 25px;
    }

    .form-group input,
    .form-group select,
    .form-group textarea {
        padding: 10px;
        font-size: 16px;
    }

    .btn-primary,
    .btn-secondary,
    .btn-danger,
    .btn-ai {
        padding: 12px 16px;
        font-size: 0.95rem;
    }

    .item-card {
        padding: 12px;
        padding-right: 70px;
    }

    .item-card h4 {
        font-size: 1rem;
    }
}

@media print {
    .mobile-nav,
    .header-controls,
    .btn-primary,
    .btn-secondary,
    .btn-danger,
    .btn-ai,
    .btn-delete,
    .input-area,
    #data-management,
    .ai-controls {
        display: none !important;
    }

    .container {
        max-width: 100%;
        padding: 0;
    }

    .section {
        box-shadow: none;
        page-break-inside: avoid;
    }

    body {
        background: white;
        color: black;
    }
}