:root {
    --primary-color: #4a90e2;
    --secondary-color: #f5f5f5;
    --text-color: #333;
    --border-color: #e0e0e0;
    --danger-color: #ff4444;
    --success-color: #00C851;
    --warning-color: #ffbb33;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #f9f9f9;
}

#app {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

header {
    margin-bottom: 20px;
}

.list-selector {
    display: flex;
    gap: 10px;
    align-items: center;
}

#taskListSelector {
    flex-grow: 1;
    padding: 8px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 16px;
}

.task-input-container {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

#newTask {
    flex-grow: 1;
    padding: 12px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s;
}

#newTask:focus {
    outline: none;
    border-color: var(--primary-color);
}

button {
    padding: 8px 16px;
    border: none;
    border-radius: 4px;
    background-color: var(--primary-color);
    color: white;
    cursor: pointer;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #357abd;
}

.icon-button {
    padding: 8px;
    background: none;
    color: var(--text-color);
}

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

.task-lists {
    flex-grow: 1;
}

.task-list {
    background: white;
    border-radius: 8px;
    padding: 16px;
    margin-bottom: 20px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.sortable-list {
    list-style: none;
}

.task-item {
    display: flex;
    align-items: center;
    padding: 12px;
    margin: 8px 0;
    background: white;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    cursor: pointer;
    transition: transform 0.2s;
}

.task-item:active {
    cursor: grabbing;
}

.task-item.sortable-ghost {
    opacity: 0.5;
}

.task-item input[type="checkbox"] {
    margin-right: 12px;
}

.task-item .task-content {
    flex-grow: 1;
    display: flex;
    align-items: center;
    gap: 8px;
}

.task-meta {
    display: flex;
    gap: 8px;
    align-items: center;
    font-size: 0.9em;
    color: #666;
}

.task-meta i {
    font-size: 14px;
}

.completed-tasks-container {
    background: white;
    border-radius: 8px;
    padding: 16px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

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

.completed-task {
    text-decoration: line-through;
    color: #888;
}

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
    z-index: 1000;
}

.modal-content {
    position: relative;
    background-color: white;
    margin: 20px auto;
    padding: 20px;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

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

.close-button {
    background: none;
    border: none;
    font-size: 24px;
    color: #666;
    cursor: pointer;
}

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 8px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
}

.form-group textarea {
    min-height: 100px;
    resize: vertical;
}

.image-preview-container {
    position: relative;
    margin-top: 10px;
}

.image-preview-container img {
    max-width: 100%;
    border-radius: 4px;
}

.task-created-at {
    text-align: right;
    color: #666;
    font-size: 0.9em;
    margin-top: 20px;
}

footer {
    margin-top: 40px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.user-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.hidden {
    display: none !important;
}

#loginContainer {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
}

.login-box {
    text-align: center;
    padding: 40px;
    background: white;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    width: 100%;
    max-width: 400px;
}

.login-box h1 {
    margin-bottom: 30px;
    color: var(--primary-color);
}

.login-tabs {
    display: flex;
    margin-bottom: 20px;
    border-bottom: 1px solid var(--border-color);
}

.tab-btn {
    flex: 1;
    padding: 10px;
    background: none;
    border: none;
    color: var(--text-color);
    cursor: pointer;
    transition: all 0.3s;
}

.tab-btn.active {
    color: var(--primary-color);
    border-bottom: 2px solid var(--primary-color);
}

.tab-content {
    display: none;
    padding: 20px 0;
}

.tab-content.active {
    display: block;
}

.auth-form {
    margin-bottom: 20px;
}

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

.auth-form input {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 16px;
    transition: border-color 0.3s;
}

.auth-form input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.submit-btn {
    width: 100%;
    padding: 12px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 4px;
    font-size: 16px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.submit-btn:hover {
    background-color: #357abd;
}

.divider {
    margin: 20px 0;
    position: relative;
    text-align: center;
    color: #666;
}

.divider::before,
.divider::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 45%;
    height: 1px;
    background-color: var(--border-color);
}

.divider::before {
    left: 0;
}

.divider::after {
    right: 0;
}

.g-signin2 {
    margin-top: 20px;
    display: flex;
    justify-content: center;
}

.past-due {
    color: var(--danger-color);
}

@media (max-width: 768px) {
    #app {
        padding: 10px;
    }

    .modal-content {
        margin: 10px;
        padding: 15px;
    }

    .task-item {
        padding: 8px;
    }
}

/* タッチデバイス用のスタイル */
@media (hover: none) {
    .task-item {
        touch-action: none;
    }
}