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

:root {
    /* Light Theme colors - soft, pastel green palette with excellent readability */
    --bg-gradient-start: #f1f8f4;
    --bg-gradient-end: #e8f5e9;
    --card-gradient-start: #c8e6c9;
    --card-gradient-end: #a5d6a7;
    --card-hover-start: #a5d6a7;
    --card-hover-end: #c8e6c9;
    --border-color: #c8e6c9;
    --text-primary: #1b5e20;
    --text-secondary: #2e7d32;
    --card-text: #1b5e20;
    --card-text-secondary: #2e7d32;
    --bg-primary: #fafdfb;
    --bg-secondary: #f1f8f4;
    --shadow-color: rgba(76,175,80,0.15);
    --success-color: #28a745;
    --danger-color: #dc3545;
    --search-highlight-start: #ffd54f;
    --search-highlight-end: #ffb300;
    --search-shadow-color: rgba(255, 179, 0, 0.4);
}

/* Dark Theme - applied when body has 'dark-theme' class or system prefers dark mode */
@media (prefers-color-scheme: dark) {
    :root:not(.light-theme) {
        /* Dark theme colors */
        --bg-gradient-start: #1a1a1a;
        --bg-gradient-end: #2d2d2d;
        --card-gradient-start: #2c2c2c;
        --card-gradient-end: #1f1f1f;
        --card-hover-start: #3a3a3a;
        --card-hover-end: #2c2c2c;
        --border-color: #444;
        --text-primary: #e0e0e0;
        --text-secondary: #b0b0b0;
        --card-text: #e0e0e0;
        --card-text-secondary: #b0b0b0;
        --bg-primary: #2d2d2d;
        --bg-secondary: #1f1f1f;
        --shadow-color: rgba(0,0,0,0.3);
        --success-color: #28a745;
        --danger-color: #dc3545;
        --search-highlight-start: #ffd54f;
        --search-highlight-end: #ffb300;
        --search-shadow-color: rgba(255, 179, 0, 0.4);
    }
}

/* Manual dark mode override */
:root.dark-theme{
    --bg-gradient-start: #1a1a1a;
    --bg-gradient-end: #2d2d2d;
    --card-gradient-start: #2c2c2c;
    --card-gradient-end: #1f1f1f;
    --card-hover-start: #3a3a3a;
    --card-hover-end: #2c2c2c;
    --border-color: #444;
    --text-primary: #e0e0e0;
    --text-secondary: #b0b0b0;
    --card-text: #e0e0e0;
    --card-text-secondary: #b0b0b0;
    --bg-primary: #2d2d2d;
    --bg-secondary: #1f1f1f;
    --shadow-color: rgba(0,0,0,0.3);
    --success-color: #28a745;
    --danger-color: #dc3545;
    --search-highlight-start: #ffd54f;
    --search-highlight-end: #ffb300;
    --search-shadow-color: rgba(255, 179, 0, 0.4);        
}

body{
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    background: linear-gradient(135deg, var(--bg-gradient-start), var(--bg-gradient-end) 100%);
    min-height: 100vh;
    padding: 10px;
}

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

header{
    background: var(--bg-primary);
    padding: 15px 20px;
    border-radius: 10px;
    margin-bottom: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 15px;
    box-shadow: 0 4px 6px var(--shadow-color);
    flex-wrap: wrap;
}

header h1{
    font-size: 24px;
    color: var(--text-primary);
}

.search-container{
    display: flex;
    align-items: center;
    gap: 8px;
    flex: 1;
    max-width: 400px;
    position: relative;
}

.search-container > div:first-child{
    position: relative;
    flex: 1;
}

#searchInput{
    width: 100%;
    padding: 8px 35px 8px 12px;
    border: 2px solid var(--border-color);
    border-radius: 20px;
    font-size: 14px;
    background: var(--bg-primary);
    color: var(--text-primary);
    transition: all 0.3s ease;
}

#searchInput:focus{
    outline: none;
    border-color: var(--card-gradient-start);
    box-shadow: 0 0 3px var(--shadow-color);
}

#searchInput::placeholder{
    color: var(--text-secondary);
    opacity: 0.6;
}

.btn-clear{
    position: absolute;
    right: 8px;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 18px;
    padding: 4px 8px;
    display: none;
    transition: color 0.3s ease;
    z-index: 1;
}

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

.btn-clear.visible{
    display: block;
}

.search-count{
    font-size: 12px;
    color: var(--text-secondary);
    white-space: nowrap;
    min-width: 70px;
    text-align: left;
    flex-shrink: 0;
}

.header-buttons{
    display: flex;
    gap: 10px;
    align-items: center;
}

.header-buttons button{
    padding: 10px 20px;
}

#exportBtn, #resetBtn {
    padding: 10px 15px;
    font-size: 18px;
}

.tree-container{
    background: var(--bg-primary);
    border-radius: 10px;
    padding: 20px;
    box-shadow: 0 4px 6px var(--shadow-color);
    overflow-x: auto;
}

/* Person Card Styles*/
.person-card{
    background: linear-gradient(135deg, var(--card-gradient-start) 0%, var(--card-gradient-end) 100%);
    color: var(--card-text);
    padding: 15px;
    border-radius: 10px;
    margin: 10px 0;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 2px 4px var(--shadow-color);
    position: relative;
}

.person-card.search-highlight{
    background: linear-gradient(135deg, var(--search-highlight-start) 0%, var(--search-highlight-end) 100%);
    box-shadow: 0 4px 12px var(--search-shadow-color);
    transform: scale(1.02);
}

.person-card.search-dimmed{
    opacity: 0.6;
}

.person-card:hover{
    transform: translateY(-2px);
    box-shadow: 0 4px 8px var(--shadow-color);
}

.person-card.editable:hover{
    background: linear-gradient(135deg, var(--card-hover-start) 0%, var(--card-hover-end) 100%);
}

.person-header{
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.person-name-container{
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 5px;
    margin-bottom: 5px;
}

.person-name{
    font-size: 16px;
    font-weight: bold;
}

.person-spouse{
    font-size: 15px;
    color: var(--card-text-secondary);
}

.person-note{
    font-size: 12px;
    color: var(--card-text-secondary);
    font-style: italic;
}

.expand-icon{
    font-size: 14px;
    transition: transform 0.3s ease;
    user-select: none;
}

.expand-icon.expanded{
    transform: rotate(90deg);
}

.edit-icon{
    position: absolute;
    top: 10px;
    right: 10px;
    background: rgba(255,255,255,0.3);
    border-radius: 50%;
    width: 30px;
    height: 30px;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    cursor: pointer;
}

.person-card.editable .edit-icon{
    display: flex;
}

/*Children Container */
.children-container{
    margin-left: 20px;
    margin-top: 10px;
    border-left: 3px solid var(--border-color);
    padding-left: 15px;
    display: none;
}

.children-container.visible{
    display: block;
}

/* Button Styles */
.btn-primary, .btn-secondary, .btn-danger{
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-primary{
    background: #2196F3;
    color: white;
}

.btn-primary:hover{
    background: #1976D2;
}

.btn-secondary{
    background: #6c757d;
    color: white;
}

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

.btn-danger{
    background: #dc3545;
    color: white;
}

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

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0,0,0,0.5);
    animation: fadeIn 0.3s ease;
}

.modal.show {
    display: block;
}

@keyframes fadeIn {
    from {opacity: 0;}
    to {opacity: 1;}
}

.modal-content {
    background-color: var(--bg-primary);
    margin: 5% auto;
    padding: 0;
    border-radius: 10px;
    width: 90%;
    max-width: 500px;
    max-height: 85vh;
    overflow-y: auto;
    box-shadow: 0 4px 20px var(--shadow-color);
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from {
        transform: translateY(-50px); 
        opacity: 0;
    }
    to {
        transform: translateY(0); 
        opacity: 1;
    }
}

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

.modal-header h2 {
    font-size: 20px;
    color: var(--text-primary);
}

.close {
    color: #aaa;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
    line-height: 1;
}

.close:hover{
    color: #000;
}

/* Form Styles */
form {
    padding: 20px;
}

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

.form-group label {
    display: block;
    margin-bottom: 5px;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 14px;
}

.form-group input {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    font-size: 14px;
    background: var(--bg-primary);
    color: var(--text-primary);
}

.form-group input:focus {
    outline: none;
    border-color: var(--card-gradient-start);
}

.form-actions {
    display: flex;
    gap: 10px;
    margin-top: 20px;
    flex-wrap: wrap;
}

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

.child-section h3{
    font-size: 18px;
    margin-bottom: 15px;
    color: var(--text-primary);
}

#childrenList {
    margin-top: 15px;
}

.child-item {
    background: var(--bg-secondary);
    padding: 10px;
    border-radius: 5px;
    margin-bottom: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.child-item-name {
    font-weight: 600;
    color: var(--text-primary);
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    header {
        flex-direction: column;
        align-items: stretch;
    }
    header h1 {
        font-size: 20px;
        text-align: center;
    }
    .search-container {
        max-width: 100%;
        order: 2; 
    }

    .header-buttons {
        order: 3; 
        justify-content: center;
    }

    .person-name-container{
        flex-direction: column;
        align-items: flex-start;
        gap: 3px;
    }

    .person-name {
        font-size: 15px;
    }

    .person-spouse {
        font-size: 14px;
    }

    .media-content{
        width: 95%;
        margin: 10% auto;
    }

    .form-actions{
        flex-direction: column;
    }

    .form-actions button {
        width: 100%;
    } 
}

@media (max-width: 480px) {
    body {
        padding: 5px;
    }

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

    header h1 {
        font-size: 18px;
    }

    .header-buttons {
        width: 100%;
        justify-content: center;
    }

    .header-buttons button {
        flex: 1;
        padding: 8px 12px;
    }

    #exportBtn, #resetBtn {
        font-size: 16px;
        padding: 8px 12px;
    }

    .tree-container {
        padding: 15px;
    }

    .person-card {
        padding: 12px;
    }

    .children-container {
        margin-left: 10px;
        padding-left: 10px;
    }
}

/* Edit Mode Indicator */
body.edit-mode .person-card{
    cursor: pointer;
}

body.edit-mode .person-card::after{
    content: '✎';
    position: absolute;
    top: 5px;
    right: 5px;
    font-size: 12px;
    opacity: 0.7;
}

/* Notification Animations */
@keyframes slideDown {
    from {
        transform: translateX(-50%) translateY(-100px);
        opacity: 0;
    }
    to {
        transform: translateX(-50%) translateY(0);
        opacity: 1;
    }
}

@keyframes slideUp {
    from {
        transform: translateX(-50%) translateY(0);
        opacity: 1;
    }
    to {
        transform: translateX(-50%) translateY(-100px);
        opacity: 0;
    }
}