:root {
    --primary-color: #ff6b35;
    --secondary-color: #f7931e;
    --accent-color: #4ecdc4;
    --text-color: #2c3e50;
    --bg-color: #f8f9fa;
    --white: #ffffff;
    --gray: #6c757d;
    --light-gray: #e9ecef;
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

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

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

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 40px;
    padding: 30px 0;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    border-radius: 15px;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
}

header p {
    font-size: 1.1rem;
    opacity: 0.9;
}

main {
    background: var(--white);
    border-radius: 15px;
    padding: 30px;
    box-shadow: var(--shadow);
}

section {
    margin-bottom: 30px;
}

h2 {
    color: var(--primary-color);
    margin-bottom: 20px;
    font-size: 1.5rem;
}

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

.input-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
    color: var(--gray);
}

.input-group input {
    width: 100%;
    padding: 10px 15px;
    border: 2px solid var(--light-gray);
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

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

.serving-adjuster {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-top: 20px;
}

.serving-adjuster .input-group {
    flex: 1;
    margin-bottom: 0;
}

.arrow {
    font-size: 2rem;
    color: var(--primary-color);
}

.ingredients-list {
    margin-bottom: 20px;
}

.ingredient-item {
    display: flex;
    gap: 10px;
    margin-bottom: 10px;
    padding: 15px;
    background: var(--light-gray);
    border-radius: 8px;
    align-items: center;
}

.ingredient-item input {
    padding: 8px 12px;
    border: 2px solid var(--white);
    border-radius: 6px;
    font-size: 0.95rem;
}

.ingredient-item input[type="number"] {
    width: 100px;
}

.ingredient-item input[type="text"]:first-of-type {
    flex: 2;
}

.ingredient-item select {
    padding: 8px 12px;
    border: 2px solid var(--white);
    border-radius: 6px;
    font-size: 0.95rem;
    background: var(--white);
    cursor: pointer;
}

.ingredient-item button {
    padding: 8px 12px;
    background: #dc3545;
    color: var(--white);
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.3s;
}

.ingredient-item button:hover {
    background: #c82333;
}

.btn-add {
    width: 100%;
    padding: 12px 20px;
    background: var(--accent-color);
    color: var(--white);
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.3s;
}

.btn-add:hover {
    background: #45b7b8;
}

.converted-section {
    background: #f0f8ff;
    padding: 25px;
    border-radius: 10px;
    margin-top: 30px;
}

.converted-list {
    margin-bottom: 20px;
}

.converted-item {
    padding: 10px 15px;
    margin-bottom: 8px;
    background: var(--white);
    border-radius: 6px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.converted-item .amount {
    color: var(--primary-color);
    font-weight: 500;
}

.action-buttons {
    display: flex;
    gap: 10px;
    justify-content: center;
}

.btn-secondary {
    padding: 10px 20px;
    background: var(--white);
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
}

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

.saved-recipes {
    margin-top: 40px;
}

.saved-recipes-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 15px;
}

.saved-recipe-item {
    padding: 20px;
    background: var(--light-gray);
    border-radius: 10px;
    cursor: pointer;
    transition: transform 0.3s, box-shadow 0.3s;
}

.saved-recipe-item:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.saved-recipe-item h3 {
    color: var(--primary-color);
    margin-bottom: 10px;
}

.saved-recipe-item p {
    color: var(--gray);
    font-size: 0.9rem;
}

.saved-recipe-item .delete-btn {
    margin-top: 10px;
    padding: 6px 12px;
    background: #dc3545;
    color: var(--white);
    border: none;
    border-radius: 5px;
    font-size: 0.85rem;
    cursor: pointer;
}

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

.modal-content {
    background-color: var(--white);
    margin: 15% auto;
    padding: 30px;
    border-radius: 15px;
    width: 90%;
    max-width: 500px;
    position: relative;
}

.close {
    position: absolute;
    right: 20px;
    top: 20px;
    font-size: 2rem;
    cursor: pointer;
    color: var(--gray);
}

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

.share-content textarea {
    width: 100%;
    height: 200px;
    padding: 15px;
    border: 2px solid var(--light-gray);
    border-radius: 8px;
    font-family: inherit;
    font-size: 0.95rem;
    resize: vertical;
    margin-bottom: 15px;
}

.btn-primary {
    width: 100%;
    padding: 12px 20px;
    background: var(--primary-color);
    color: var(--white);
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background 0.3s;
}

.btn-primary:hover {
    background: #e55a2b;
}

footer {
    text-align: center;
    margin-top: 40px;
    padding: 20px;
    color: var(--gray);
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }

    header h1 {
        font-size: 2rem;
    }

    main {
        padding: 20px;
    }

    .serving-adjuster {
        flex-direction: column;
        gap: 10px;
    }

    .arrow {
        transform: rotate(90deg);
    }

    .ingredient-item {
        flex-wrap: wrap;
    }

    .ingredient-item input[type="number"] {
        width: 80px;
    }

    .action-buttons {
        flex-direction: column;
    }

    .btn-secondary {
        width: 100%;
    }
}

/* アニメーション */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.ingredient-item,
.converted-item,
.saved-recipe-item {
    animation: fadeIn 0.3s ease-out;
}

/* トースト通知 */
.toast {
    position: fixed;
    bottom: 20px;
    right: 20px;
    padding: 15px 25px;
    background: var(--text-color);
    color: var(--white);
    border-radius: 8px;
    box-shadow: var(--shadow);
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.3s;
    z-index: 2000;
}

.toast.show {
    opacity: 1;
    transform: translateY(0);
}

.toast.success {
    background: #28a745;
}

.toast.error {
    background: #dc3545;
}