:root {
    /* Light mode (default) - matching screenshot */
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    --bg-card: #ffffff;
    --text-primary: #1a1a1a;
    --text-secondary: #666666;
    --text-tertiary: #999999;
    --border-color: #dee2e6;
    --border-color-hover: #ced4da;
    --accent-color: #ff69b4;
    --accent-hover: #ff1493;
    --accent-light: #ffb6d9;
    --success-bg: #d4edda;
    --success-text: #155724;
    --success-border: #c3e6cb;
    --error-bg: #f8d7da;
    --error-text: #dc3545;
    --error-border: #f5c6cb;
    --button-primary: #ff69b4;
    --button-primary-hover: #ff1493;
    --button-secondary: #6c757d;
    --button-secondary-hover: #5a6268;
    --shadow: rgba(0, 0, 0, 0.08);
    --shadow-hover: rgba(0, 0, 0, 0.12);
}

[data-theme="dark"] {
    /* Dark mode - matching screenshot */
    --bg-primary: #1a1a1a;
    --bg-secondary: #2a2a2a;
    --bg-tertiary: #3a3a3a;
    --bg-card: #2a2a2a;
    --text-primary: #e8e8e8;
    --text-secondary: #b0b0b0;
    --text-tertiary: #808080;
    --border-color: #404040;
    --border-color-hover: #505050;
    --accent-color: #ff69b4;
    --accent-hover: #ff1493;
    --accent-light: rgba(255, 105, 180, 0.2);
    --success-bg: #1e4d2e;
    --success-text: #90ee90;
    --success-border: #2e5d3e;
    --error-bg: #4d1e1e;
    --error-text: #ff6b6b;
    --error-border: #5d2e2e;
    --button-primary: #ff69b4;
    --button-primary-hover: #ff1493;
    --button-secondary: #6c757d;
    --button-secondary-hover: #7d8e9f;
    --shadow: rgba(0, 0, 0, 0.4);
    --shadow-hover: rgba(0, 0, 0, 0.5);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-secondary);
    min-height: 100vh;
    padding: 20px;
    color: var(--text-primary);
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background: transparent;
    border-radius: 0;
    box-shadow: none;
    padding: 30px 40px;
    border: none;
    transition: background-color 0.3s ease;
}

header {
    margin-bottom: 35px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

.header-top {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 20px;
}

.header-title {
    flex: 1;
    min-width: 0;
}

header h1 {
    color: var(--text-primary);
    font-size: 1.6em;
    margin-bottom: 8px;
    font-weight: 600;
    letter-spacing: -0.3px;
    line-height: 1.3;
}

.project-subtitle {
    display: block;
    font-size: 0.5em;
    font-weight: 400;
    margin-top: 4px;
    line-height: 1.4;
}

.project-start {
    color: var(--text-secondary);
    font-size: 0.85em;
    font-weight: 400;
    margin: 0;
}

/* Theme Toggle */
.theme-toggle-container {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}

.toggle-label {
    color: var(--text-secondary);
    font-size: 0.9em;
    font-weight: 500;
}

.theme-toggle {
    position: relative;
    display: inline-block;
    width: 50px;
    height: 26px;
    cursor: pointer;
}

.theme-toggle input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--bg-tertiary);
    transition: 0.3s;
    border-radius: 26px;
    border: 1px solid var(--border-color);
}

.slider:before {
    position: absolute;
    content: "";
    height: 20px;
    width: 20px;
    left: 3px;
    bottom: 2px;
    background-color: var(--bg-primary);
    transition: 0.3s;
    border-radius: 50%;
    box-shadow: 0 2px 4px var(--shadow);
}

.theme-toggle input:checked + .slider {
    background-color: var(--bg-tertiary);
    border-color: var(--border-color);
}

.theme-toggle input:checked + .slider:before {
    transform: translateX(24px);
    background-color: var(--text-primary);
}

.form-section {
    margin-bottom: 25px;
    padding: 25px;
    background: transparent;
    border-radius: 0;
    border: 1px solid var(--border-color);
    transition: border-color 0.3s ease;
}

.form-section h2 {
    color: var(--text-primary);
    font-size: 1.3em;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border-color);
    font-weight: 600;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.contact-actions {
    display: flex;
    gap: 10px;
    align-items: center;
}

.btn-remove {
    padding: 12px 16px !important;
    min-width: 40px;
}

.section-header h2 {
    margin-bottom: 0;
    border-bottom: none;
}

.form-group {
    margin-bottom: 18px;
}

.form-group label {
    display: block;
    margin-bottom: 6px;
    color: var(--text-primary);
    font-weight: 500;
    font-size: 0.9em;
}

.required-asterisk {
    color: var(--accent-color);
    font-weight: 600;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 0.95em;
    transition: all 0.2s ease;
    font-family: inherit;
    background: var(--bg-primary);
    color: var(--text-primary);
}

.form-group input:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px var(--accent-light);
}

.form-group input:invalid:not(:placeholder-shown):focus,
.form-group select:invalid:focus {
    border-color: var(--border-color);
    box-shadow: none;
}

.form-group input::placeholder {
    color: var(--text-tertiary);
}

.contact-item {
    background: transparent;
    padding: 20px;
    margin-bottom: 15px;
    border-radius: 0;
    border: 1px solid var(--border-color);
    position: relative;
    transition: border-color 0.3s ease;
}

.contact-item:hover {
    border-color: var(--border-color-hover);
}

.contact-item-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.contact-item-header h3 {
    color: var(--accent-color);
    font-size: 1.05em;
    font-weight: 600;
    margin: 0;
}

.remove-contact {
    background: transparent;
    color: var(--accent-color);
    border: 1px solid var(--accent-color);
    padding: 6px 10px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1em;
    transition: all 0.2s ease;
    font-weight: 400;
    opacity: 0.7;
    line-height: 1;
}

.remove-contact:hover {
    opacity: 1;
    background: var(--accent-light);
}

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

@media (max-width: 700px) {
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .header-top {
        flex-wrap: wrap;
    }
    
    .header-title {
        width: 100%;
        margin-bottom: 15px;
    }
    
    .theme-toggle-container {
        margin-left: auto;
    }
}

.form-actions {
    margin-top: 30px;
    display: flex;
    justify-content: flex-end;
    align-items: center;
}

.btn-primary,
.btn-secondary {
    padding: 12px 28px;
    border: none;
    border-radius: 4px;
    font-size: 1em;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    font-family: inherit;
    letter-spacing: 0.2px;
}

.btn-primary {
    background: var(--button-primary);
    color: white;
    box-shadow: 0 2px 6px var(--shadow);
}

.btn-primary.btn-disabled {
    background: var(--button-secondary);
    color: var(--text-primary);
    box-shadow: none;
    cursor: not-allowed;
    opacity: 1;
}

.btn-primary:hover:not(:disabled):not(.btn-disabled) {
    background: var(--button-primary-hover);
    box-shadow: 0 4px 10px var(--shadow-hover);
    transform: translateY(-1px);
}

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

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.btn-secondary {
    background: var(--button-secondary);
    color: white;
}

.btn-secondary:hover {
    background: var(--button-secondary-hover);
}

.message {
    margin-top: 20px;
    padding: 15px;
    border-radius: 4px;
    text-align: center;
    font-weight: 500;
    display: none;
    border: 1px solid;
}

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

.message.error {
    background: var(--error-bg);
    color: var(--error-text);
    border-color: var(--error-border);
    display: block;
}

.admin-view {
    margin-top: 40px;
    padding: 25px;
    background: var(--bg-secondary);
    border-radius: 6px;
    border: 1px solid var(--border-color);
}

.admin-actions {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-primary);
    border-radius: 4px;
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.data-table th,
.data-table td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.data-table th {
    background: var(--accent-color);
    color: white;
    font-weight: 600;
}

.data-table tr:hover {
    background: var(--bg-secondary);
}

.empty-state {
    text-align: center;
    padding: 40px;
    color: var(--text-secondary);
}

/* Privacy Notice */
.privacy-notice {
    margin-top: 30px;
    padding: 15px 20px;
    background: transparent;
    border-radius: 0;
    border-left: 1px solid var(--border-color);
}

.privacy-notice p {
    color: var(--text-secondary);
    font-size: 0.85em;
    line-height: 1.6;
    margin: 0;
}

/* Footer */
footer {
    margin-top: 40px;
    padding-top: 30px;
    border-top: 1px solid var(--border-color);
    text-align: center;
}

.footer-logo-link {
    display: inline-block;
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.2s ease;
}

.footer-logo-link:hover {
    opacity: 1;
}

.footer-logo {
    height: 30px;
    width: auto;
    object-fit: contain;
}

.footer-contact {
    margin-top: 20px;
    color: var(--text-secondary);
    font-size: 0.9em;
    line-height: 1.8;
}

.footer-contact p {
    margin: 4px 0;
}

.footer-contact a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.2s ease;
}

.footer-contact a:hover {
    color: var(--text-primary);
}

@media (max-width: 600px) {
    .container {
        padding: 20px;
    }

    header h1 {
        font-size: 1.4em;
    }

    .form-section {
        padding: 18px;
    }
}

/* Smooth transitions for theme switching */
* {
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

/* Override for inputs and buttons to prevent color transitions */
input, select, button {
    transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease !important;
}

/* Project Selection Styles */
.project-selection {
    margin-bottom: 25px;
}

.project-details {
    margin-top: 15px;
    padding: 15px;
    background: var(--accent-light);
    border-radius: 4px;
    border-left: 3px solid var(--accent-color);
}

.project-details .project-title {
    font-weight: 600;
    color: var(--text-primary);
    margin: 0 0 5px 0;
    font-size: 1.1em;
}

.project-details .project-subtitle-text {
    color: var(--text-secondary);
    margin: 0;
    font-size: 0.95em;
}

/* Loading state for select */
.form-group select:disabled {
    background-color: var(--bg-tertiary);
    cursor: wait;
}