/* ===== 全体背景 ===== */
body {
    margin: 0;
    padding: 0;
    font-family: system-ui, -apple-system, BlinkMacSystemFont,
                "Hiragino Sans", "Noto Sans JP", sans-serif;
}

.auth-bg {
    min-height: 100vh;
    background: radial-gradient(circle at top left, #a0c9ff 0, transparent 60%),
                radial-gradient(circle at bottom right, #ffd6a8 0, transparent 55%),
                #f5f7fb;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 24px;
}

/* ===== カード ===== */
.auth-card {
    width: 100%;
    max-width: 720px;
    background: #ffffff;
    border-radius: 18px;
    box-shadow: 0 18px 45px rgba(15, 23, 42, 0.20);
    padding: 28px 32px 26px;
    box-sizing: border-box;
}

/* ===== ヘッダー部分（タイトル＋ロゴ） ===== */
.auth-header {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 18px;
}

.auth-logo-circle {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: linear-gradient(135deg, #4d8ef7, #7a5cff);
    display: flex;
    justify-content: center;
    align-items: center;
    color: #ffffff;
    font-weight: 700;
    font-size: 18px;
    box-shadow: 0 8px 18px rgba(77, 142, 247, 0.5);
}

.auth-title {
    margin: 0;
    font-size: 22px;
    font-weight: 700;
    color: #1f2933;
}

.auth-subtitle {
    margin: 4px 0 0;
    font-size: 13px;
    color: #6b7280;
}

/* ===== メッセージ ===== */
.messages {
    margin: 8px 0 12px;
}

.msg {
    padding: 8px 10px;
    border-radius: 8px;
    font-size: 13px;
    margin-bottom: 6px;
}

.msg.error {
    background: #ffe2df;
    color: #b91c1c;
}

.msg.success {
    background: #def7ec;
    color: #047857;
}

/* ===== フォームグリッド ===== */
.auth-form {
    margin-top: 6px;
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px 18px;
}

/* スマホでは1カラムに */
@media (max-width: 640px) {
    .auth-card {
        padding: 22px 18px 20px;
    }
    .form-grid {
        grid-template-columns: 1fr;
    }
}

.form-field {
    display: flex;
    flex-direction: column;
}

.form-field.full {
    grid-column: 1 / -1;
}

.form-field label {
    font-size: 12px;
    font-weight: 600;
    color: #4b5563;
    margin-bottom: 4px;
}

/* 入力欄 */
.form-field input {
    padding: 10px 11px;
    font-size: 14px;
    border-radius: 9px;
    border: 1px solid #d1d5db;
    outline: none;
    background-color: #f9fafb;
    transition: border-color 0.18s ease, box-shadow 0.18s ease,
                background-color 0.18s ease, transform 0.05s ease;
}

.form-field input::placeholder {
    color: #9ca3af;
}

.form-field input:focus {
    background-color: #ffffff;
    border-color: #4d8ef7;
    box-shadow: 0 0 0 1px rgba(77, 142, 247, 0.35);
    transform: translateY(-1px);
}

/* ===== ボタン ===== */
.auth-btn {
    margin-top: 18px;
    width: 100%;
    padding: 11px;
    border-radius: 999px;
    border: none;
    background: linear-gradient(135deg, #4d8ef7, #7a5cff);
    color: #ffffff;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    letter-spacing: 0.03em;
    box-shadow: 0 12px 24px rgba(79, 70, 229, 0.45);
    transition: transform 0.1s ease, box-shadow 0.1s ease, opacity 0.15s ease;
}

.auth-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 16px 30px rgba(79, 70, 229, 0.55);
    opacity: 0.95;
}

.auth-btn:active {
    transform: translateY(1px);
    box-shadow: 0 8px 16px rgba(79, 70, 229, 0.4);
}

/* ===== フッターリンク ===== */
.auth-footer {
    margin-top: 14px;
    font-size: 13px;
    color: #6b7280;
    text-align: right;
}

.auth-footer a {
    margin-left: 4px;
    color: #4d8ef7;
    text-decoration: none;
    font-weight: 500;
}

.auth-footer a:hover {
    text-decoration: underline;
}


/* スマホ対応 */
@media (max-width: 480px) {
    .auth-card {
        padding: 24px 18px;
    }
}