* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Trebuchet MS", sans-serif;
}

/* Make html and body fill the full viewport */
body,
html {
    width: 100%;
    min-height: 100%;
    overflow-x: hidden;
    overflow-y: auto;
}

.page {
    width: 100%;
    min-height: 100vh;
    min-height: 100svh;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    padding: 48px 16px 24px;
    background-image: url('/static/images/sign-in-picture.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    position: relative;
}

.site-title {
    color: #ffffff;
    font-size: clamp(32px, 7vw, 44px);
    font-weight: 300;
    letter-spacing: 2px;
    margin-bottom: 30px;
    text-shadow: 0 4px 15px rgba(0, 0, 0, 0.4);
    text-align: center;
}


/* login-card 和 signup-card 共用 */
.login-card,
.signup-card {
    background: rgba(255, 255, 255, 0.6);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.5);
    width: 100%; /* 宽度不写死，能自适应屏幕 */    
    max-width: 420px;
    padding: 40px 32px;
    border-radius: 16px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.2);
    display: flex;
    flex-direction: column;
}

.login-card h2,
.signup-card h2 {
    font-size: 18px;
    font-weight: bold;
    color: #1F3A5F;
    margin-bottom: 35px;
    position: relative;
    display: inline-block;
    align-self: flex-start;
}

.login-card h2::after,
.signup-card h2::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -10px;
    width: 100%;
    height: 3px;
    background-color: #1E73D8;
    border-radius: 2px;
}

form {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.form-error {
    color: #d93025;
    font-size: 13px;
    margin-top: -2px;
    margin-bottom: -6px;
    min-height: 16px;
    text-align: left;
}

.form-error.is-hidden {
    visibility: hidden;
}

input[type="text"],
input[type="email"],
input[type="password"] {
    width: 100%;
    padding: 14px 20px;
    border: 1px solid #e8e8e8;
    border-radius: 25px;
    font-size: 14px;
    color: #333333;
    outline: none;
    transition: border-color 0.3s;
}

input[type="text"]::placeholder,
input[type="email"]::placeholder,
input[type="password"]::placeholder {
    color: #cccccc;
}

input[type="text"]:focus,
input[type="email"]:focus,
input[type="password"]:focus {
    border-color: #002FA7;
}

.submit {
    width: 100%;
    padding: 14px;
    background-color: #1E73D8;
    border: none;
    border-radius: 25px;
    color: #ffffff;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    margin-top: 20px;
    transition: background-color 0.3s;
}

.submit:hover {
    background-color: #002FA7;
}

/* Blue underline */
.switch-to-sign-up,
.switch-to-sign-in {
    margin-top: 25px;
    text-align: center;
    font-size: 13px;
    color: #1F3A5F;
    font-weight: 500;
}

.switch-to-sign-up a,
.switch-to-sign-in a {
    color: #1F3A5F;
    text-decoration: none;
    margin-left: 5px;
    font-weight: bold;
}

.switch-to-sign-up a:hover,
.switch-to-sign-in a:hover {
    text-decoration: underline;
}

@media (max-width: 640px) {
    .page {
        padding: 40px 16px 24px;
    }

    .site-title {
        margin-bottom: 22px;
        letter-spacing: 1px;
    }

    .login-card,
    .signup-card {
        padding: 28px 20px;
        border-radius: 14px;
    }

    .login-card h2,
    .signup-card h2 {
        margin-bottom: 28px;
    }

    input[type="text"],
    input[type="email"],
    input[type="password"] {
        padding: 13px 16px;
    }

    .submit {
        margin-top: 16px;
    }
}

@media (max-width: 400px) {
    .page {
        padding-left: 12px;
        padding-right: 12px;
    }

    .login-card,
    .signup-card {
        padding: 24px 16px;
    }

    .site-title {
        font-size: clamp(28px, 8vw, 32px);
    }
}

/* @media (min-width: 900px) and (min-height: 900px) {
    .page {
        justify-content: center;
        padding-top: 24px;
        padding-bottom: 24px;
    }
} */