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

body {
    font-family: 'Arial', 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', 'Meiryo', sans-serif;
    background-color: #ffffff;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.login-container {
    background: #ffffff;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 102, 204, 0.1);
    border: 1px solid #e6f2ff;
    padding: 50px;
    width: 100%;
    max-width: 520px;
    margin: 0 20px;
}

.logo-section {
    text-align: center;
    margin-bottom: 40px;
}

.logo-container {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 30px;
    margin-bottom: 20px;
}

.logo-image {
    height: 40px;
    object-fit: contain;
}

.logo-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, #0066cc, #0052a3);
    border-radius: 12px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
    box-shadow: 0 4px 12px rgba(0, 102, 204, 0.3);
    display: none;
}

.logo-icon::before {
    content: "📥";
    font-size: 24px;
    filter: brightness(0) invert(1);
}

h1 {
    color: #0066cc;
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 8px;
    white-space: nowrap;
}

.subtitle {
    color: #666;
    font-size: 16px;
}

.form-group {
    margin-bottom: 24px;
}

.button-group {
    margin-top: 30px;
}

label {
    display: block;
    margin-bottom: 10px;
    color: #333;
    font-size: 15px;
    font-weight: 500;
}

input[type="email"],
input[type="password"] {
    width: 100%;
    padding: 16px 18px;
    border: 2px solid #e6f2ff;
    border-radius: 8px;
    font-size: 16px;
    background-color: #fafcff;
    transition: all 0.3s ease;
}

input[type="email"]::placeholder,
input[type="password"]::placeholder {
    color: #999;
    font-size: 15px;
}

input[type="email"]:focus,
input[type="password"]:focus {
    outline: none;
    border-color: #0066cc;
    background-color: #ffffff;
    box-shadow: 0 0 0 4px rgba(0, 102, 204, 0.1);
}

.login-button {
    width: 100%;
    padding: 18px;
    background: linear-gradient(135deg, #0066cc, #0052a3);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 17px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    margin-bottom: 20px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.login-button:hover {
    background: linear-gradient(135deg, #0052a3, #004080);
    box-shadow: 0 4px 16px rgba(0, 102, 204, 0.3);
    transform: translateY(-2px);
}

.login-button:active {
    transform: translateY(0);
}

.footer {
    width: 100%;
    text-align: center;
    color: #666;
    font-size: 13px;
    max-width: 600px;
    line-height: 1.5;
    padding: 24px 20px 0 20px;
    margin: 0 auto;
}

.help-text {
    margin-bottom: 15px;
    color: #555;
    font-size: 13px;
}

/* レスポンシブデザイン */
@media (max-width: 768px) {
    .login-container {
        padding: 40px 30px;
        margin: 0 15px;
    }

    .logo-container {
        flex-direction: column;
        gap: 20px;
    }

    .logo-image {
        height: 35px;
    }

    h1 {
        font-size: 22px;
    }

    .subtitle {
        font-size: 15px;
    }

    .footer {
        padding: 15px;
    }

    .help-text {
        font-size: 12px;
    }
}

@media (max-width: 480px) {
    body {
        padding: 15px;
    }

    .login-container {
        padding: 30px 25px;
        margin: 0 10px;
    }

    .logo-container {
        gap: 15px;
    }

    .logo-image {
        height: 30px;
    }

    h1 {
        font-size: 20px;
        white-space: normal;
    }

    .subtitle {
        font-size: 14px;
    }

    label {
        font-size: 14px;
    }

    input[type="email"],
    input[type="password"] {
        padding: 14px 16px;
        font-size: 16px;
    }

    input[type="email"]::placeholder,
    input[type="password"]::placeholder {
        font-size: 14px;
    }

    .login-button {
        padding: 16px;
        font-size: 16px;
    }

    .footer {
        padding: 10px;
    }

    .help-text {
        font-size: 11px;
        line-height: 1.4;
    }
}

/* アニメーション効果 */
.login-container {
    animation: slideUp 0.6s ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}